• Java Arrays
  • Java Strings
  • Java Collection
  • Java 8 Tutorial
  • Java Multithreading
  • Java Exception Handling
  • Java Programs
  • Java Project
  • Java Collections Interview
  • Java Interview Questions
  • Spring Boot
  • Java Tutorial

Overview of Java

  • Introduction to Java
  • The Complete History of Java Programming Language
  • C++ vs Java vs Python
  • How to Download and Install Java for 64 bit machine?
  • Setting up the environment in Java
  • How to Download and Install Eclipse on Windows?
  • JDK in Java
  • How JVM Works - JVM Architecture?
  • Differences between JDK, JRE and JVM
  • Just In Time Compiler
  • Difference between JIT and JVM in Java
  • Difference between Byte Code and Machine Code
  • How is Java platform independent?

Basics of Java

  • Java Basic Syntax
  • Java Hello World Program
  • Java Data Types
  • Primitive data type vs. Object data type in Java with Examples
  • Java Identifiers

Operators in Java

Java variables.

  • Scope of Variables In Java

Wrapper Classes in Java

Input/output in java.

  • How to Take Input From User in Java?
  • Scanner Class in Java
  • Java.io.BufferedReader Class in Java
  • Difference Between Scanner and BufferedReader Class in Java
  • Ways to read input from console in Java
  • System.out.println in Java
  • Difference between print() and println() in Java
  • Formatted Output in Java using printf()
  • Fast I/O in Java in Competitive Programming

Flow Control in Java

  • Decision Making in Java (if, if-else, switch, break, continue, jump)
  • Java if statement with Examples
  • Java if-else
  • Java if-else-if ladder with Examples
  • Loops in Java
  • For Loop in Java
  • Java while loop with Examples
  • Java do-while loop with Examples
  • For-each loop in Java
  • Continue Statement in Java
  • Break statement in Java
  • Usage of Break keyword in Java
  • return keyword in Java
  • Java Arithmetic Operators with Examples
  • Java Unary Operator with Examples
  • Java Assignment Operators with Examples
  • Java Relational Operators with Examples
  • Java Logical Operators with Examples
  • Java Ternary Operator with Examples
  • Bitwise Operators in Java
  • Strings in Java
  • String class in Java
  • Java.lang.String class in Java | Set 2
  • Why Java Strings are Immutable?
  • StringBuffer class in Java
  • StringBuilder Class in Java with Examples
  • String vs StringBuilder vs StringBuffer in Java
  • StringTokenizer Class in Java
  • StringTokenizer Methods in Java with Examples | Set 2
  • StringJoiner Class in Java
  • Arrays in Java
  • Arrays class in Java
  • Multidimensional Arrays in Java
  • Different Ways To Declare And Initialize 2-D Array in Java
  • Jagged Array in Java
  • Final Arrays in Java
  • Reflection Array Class in Java
  • util.Arrays vs reflect.Array in Java with Examples

OOPS in Java

  • Object Oriented Programming (OOPs) Concept in Java
  • Why Java is not a purely Object-Oriented Language?
  • Classes and Objects in Java
  • Naming Conventions in Java
  • Java Methods

Access Modifiers in Java

  • Java Constructors
  • Four Main Object Oriented Programming Concepts of Java

Inheritance in Java

Abstraction in java, encapsulation in java, polymorphism in java, interfaces in java.

  • 'this' reference in Java
  • Inheritance and Constructors in Java
  • Java and Multiple Inheritance
  • Interfaces and Inheritance in Java
  • Association, Composition and Aggregation in Java
  • Comparison of Inheritance in C++ and Java
  • abstract keyword in java
  • Abstract Class in Java
  • Difference between Abstract Class and Interface in Java
  • Control Abstraction in Java with Examples
  • Difference Between Data Hiding and Abstraction in Java
  • Difference between Abstraction and Encapsulation in Java with Examples
  • Difference between Inheritance and Polymorphism
  • Dynamic Method Dispatch or Runtime Polymorphism in Java
  • Difference between Compile-time and Run-time Polymorphism in Java

Constructors in Java

  • Copy Constructor in Java
  • Constructor Overloading in Java
  • Constructor Chaining In Java with Examples
  • Private Constructors and Singleton Classes in Java

Methods in Java

  • Static methods vs Instance methods in Java
  • Abstract Method in Java with Examples
  • Overriding in Java
  • Method Overloading in Java
  • Difference Between Method Overloading and Method Overriding in Java
  • Differences between Interface and Class in Java
  • Functional Interfaces in Java
  • Nested Interface in Java
  • Marker interface in Java
  • Comparator Interface in Java with Examples
  • Need of Wrapper Classes in Java
  • Different Ways to Create the Instances of Wrapper Classes in Java
  • Character Class in Java
  • Java.Lang.Byte class in Java
  • Java.Lang.Short class in Java
  • Java.lang.Integer class in Java
  • Java.Lang.Long class in Java
  • Java.Lang.Float class in Java
  • Java.Lang.Double Class in Java
  • Java.lang.Boolean Class in Java
  • Autoboxing and Unboxing in Java
  • Type conversion in Java with Examples

Keywords in Java

  • Java Keywords
  • Important Keywords in Java
  • Super Keyword in Java
  • final Keyword in Java
  • static Keyword in Java
  • enum in Java
  • transient keyword in Java
  • volatile Keyword in Java
  • final, finally and finalize in Java
  • Public vs Protected vs Package vs Private Access Modifier in Java
  • Access and Non Access Modifiers in Java

Memory Allocation in Java

  • Java Memory Management
  • How are Java objects stored in memory?
  • Stack vs Heap Memory Allocation
  • How many types of memory areas are allocated by JVM?
  • Garbage Collection in Java
  • Types of JVM Garbage Collectors in Java with implementation details
  • Memory leaks in Java
  • Java Virtual Machine (JVM) Stack Area

Classes of Java

  • Understanding Classes and Objects in Java
  • Singleton Method Design Pattern in Java
  • Object Class in Java
  • Inner Class in Java
  • Throwable Class in Java with Examples

Packages in Java

  • Packages In Java
  • How to Create a Package in Java?
  • Java.util Package in Java
  • Java.lang package in Java
  • Java.io Package in Java
  • Java Collection Tutorial

Exception Handling in Java

  • Exceptions in Java
  • Types of Exception in Java with Examples
  • Checked vs Unchecked Exceptions in Java
  • Java Try Catch Block
  • Flow control in try catch finally in Java
  • throw and throws in Java
  • User-defined Custom Exception in Java
  • Chained Exceptions in Java
  • Null Pointer Exception In Java
  • Exception Handling with Method Overriding in Java
  • Multithreading in Java
  • Lifecycle and States of a Thread in Java
  • Java Thread Priority in Multithreading
  • Main thread in Java
  • Java.lang.Thread Class in Java
  • Runnable interface in Java
  • Naming a thread and fetching name of current thread in Java
  • What does start() function do in multithreading in Java?
  • Difference between Thread.start() and Thread.run() in Java
  • Thread.sleep() Method in Java With Examples
  • Synchronization in Java
  • Importance of Thread Synchronization in Java
  • Method and Block Synchronization in Java
  • Lock framework vs Thread synchronization in Java
  • Difference Between Atomic, Volatile and Synchronized in Java
  • Deadlock in Java Multithreading
  • Deadlock Prevention And Avoidance
  • Difference Between Lock and Monitor in Java Concurrency
  • Reentrant Lock in Java

File Handling in Java

  • Java.io.File Class in Java
  • Java Program to Create a New File
  • Different ways of Reading a text file in Java
  • Java Program to Write into a File
  • Delete a File Using Java
  • File Permissions in Java
  • FileWriter Class in Java
  • Java.io.FileDescriptor in Java
  • Java.io.RandomAccessFile Class Method | Set 1
  • Regular Expressions in Java
  • Regex Tutorial - How to write Regular Expressions?
  • Matcher pattern() method in Java with Examples
  • Pattern pattern() method in Java with Examples
  • Quantifiers in Java
  • java.lang.Character class methods | Set 1
  • Java IO : Input-output in Java with Examples
  • Java.io.Reader class in Java
  • Java.io.Writer Class in Java
  • Java.io.FileInputStream Class in Java
  • FileOutputStream in Java
  • Java.io.BufferedOutputStream class in Java
  • Java Networking
  • TCP/IP Model
  • User Datagram Protocol (UDP)
  • Differences between IPv4 and IPv6
  • Difference between Connection-oriented and Connection-less Services
  • Socket Programming in Java
  • java.net.ServerSocket Class in Java
  • URL Class in Java with Examples

JDBC - Java Database Connectivity

  • Introduction to JDBC (Java Database Connectivity)
  • JDBC Drivers
  • Establishing JDBC Connection in Java
  • Types of Statements in JDBC
  • JDBC Tutorial
  • Java 8 Features - Complete Tutorial

In Java, Variables are the data containers that save the data values during Java program execution. Every Variable in Java is assigned a data type that designates the type and quantity of value it can hold. A variable is a memory location name for the data.

Variables in Java

Java variable is a name given to a memory location. It is the basic unit of storage in a program.

  • The value stored in a variable can be changed during program execution.
  • Variables in Java are only a name given to a memory location. All the operations done on the variable affect that memory location.
  • In Java, all variables must be declared before use.

How to Declare Variables in Java?

We can declare variables in Java as pictorially depicted below as a visual aid.

Variables in Java

From the image, it can be easily perceived that while declaring a variable, we need to take care of two things that are:

  • datatype : Type of data that can be stored in this variable. 
  • data_name: Name was given to the variable. 

In this way, a name can only be given to a memory location. It can be assigned values in two ways: 

  • Variable Initialization
  • Assigning value by taking input

How to Initialize Variables in Java?

It can be perceived with the help of 3 components that are as follows:

  • datatype : Type of data that can be stored in this variable.
  • variable_name : Name given to the variable.
  • value : It is the initial value stored in the variable.

Java Variables Syntax

Illustrations:  

Types of Variables in Java

Now let us discuss different types of variables  which are listed as follows: 

  • Local Variables
  • Instance Variables
  • Static Variables

Types of Variables in Java

Let us discuss the traits of every type of variable listed here in detail.

1. Local Variables  

A variable defined within a block or method or constructor is called a local variable. 

  • These variables are created when the block is entered, or the function is called and destroyed after exiting from the block or when the call returns from the function.
  • The scope of these variables exists only within the block in which the variables are declared, i.e., we can access these variables only within that block.
  • Initialization of the local variable is mandatory before using it in the defined scope.

Time Complexity of the Method:

Below is the implementation of the above approach:

2. Instance Variables

Instance variables are non-static variables and are declared in a class outside of any method, constructor, or block. 

  • As instance variables are declared in a class, these variables are created when an object of the class is created and destroyed when the object is destroyed.
  • Unlike local variables, we may use access specifiers for instance variables. If we do not specify any access specifier, then the default access specifier will be used.
  • Initialization of an instance variable is not mandatory. Its default value is dependent on the data type of variable. For String it is null, for float it is 0.0f, for int it is 0, for Wrapper classes like Integer it is null, etc.
  • Instance variables can be accessed only by creating objects.
  • We initialize instance variables using constructors while creating an object. We can also use instance blocks to initialize the instance variables.

The complexity of the method:

3. static variables.

Static variables are also known as class variables. 

  • These variables are declared similarly to instance variables. The difference is that static variables are declared using the static keyword within a class outside of any method, constructor, or block.
  • Unlike instance variables, we can only have one copy of a static variable per class, irrespective of how many objects we create.
  • Static variables are created at the start of program execution and destroyed automatically when execution ends.
  • Initialization of a static variable is not mandatory. Its default value is dependent on the data type of variable. For String it is null , for float it is 0.0f , for int it is 0 , for Wrapper classes like Integer it is null, etc.
  • If we access a static variable like an instance variable (through an object), the compiler will show a warning message, which won’t halt the program. The compiler will replace the object name with the class name automatically.
  • If we access a static variable without the class name, the compiler will automatically append the class name. But for accessing the static variable of a different class, we must mention the class name as 2 different classes might have a static variable with the same name.
  • Static variables cannot be declared locally inside an instance method.
  • Static blocks can be used to initialize static variables.

Differences Between the Instance Variables and the Static Variables

Now let us discuss the differences between the Instance variables and the Static variables:

  • Each object will have its own copy of an instance variable, whereas we can only have one copy of a static variable per class, irrespective of how many objects we create. Thus, static variables are good for memory management .
  • Changes made in an instance variable using one object will not be reflected in other objects as each object has its own copy of the instance variable. In the case of a static variable, changes will be reflected in other objects as static variables are common to all objects of a class.
  • We can access instance variables through object references, and static variables can be accessed directly using the class name .
  • Instance variables are created when an object is created with the use of the keyword ‘new’ and destroyed when the object is destroyed. Static variables are created when the program starts and destroyed when the program stops.

Syntax: Static and instance variables

The Important points to remember in the articles are mentioned below:

  • Variables in Java is a data container that saves the data values during Java program execution.
  • There are three types of variables in Java Local variables, static variables, and instance variables.

FAQs on Variables in Java

Q1. what are variables in java.

Variables are the containers in Java that can store data values inside them.

Q2. What are the 3 types of variables in Java?

There are three types of variables in Java are mentioned below: Local Variables Static Variables Instance Variables

Q3. How to declare variables in Java examples?

We can declare variables in java with syntax as mentioned below: data_type variable_name; Example: // Integer datatype with var1 name int var1;
  • Rules of Variable Declaration in Java
  • Scope of Variables in Java
  • Comparison of static keywords in C++ and Java
  • Are static local variables allowed in Java?
  • Instance Variable Hiding in Java

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  • 1.1 Preface
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  • 1.6 Casting and Ranges of Variables
  • 1.7 Java Development Environments (optional)
  • 1.8 Unit 1 Summary
  • 1.9 Unit 1 Mixed Up Code Practice
  • 1.10 Unit 1 Coding Practice
  • 1.11 Multiple Choice Exercises
  • 1.12 Lesson Workspace
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1.4. Expressions and Assignment Statements ¶

In this lesson, you will learn about assignment statements and expressions that contain math operators and variables.

1.4.1. Assignment Statements ¶

Remember that a variable holds a value that can change or vary. Assignment statements initialize or change the value stored in a variable using the assignment operator = . An assignment statement always has a single variable on the left hand side of the = sign. The value of the expression on the right hand side of the = sign (which can contain math operators and other variables) is copied into the memory location of the variable on the left hand side.

Assignment statement

Figure 1: Assignment Statement (variable = expression) ¶

Instead of saying equals for the = operator in an assignment statement, say “gets” or “is assigned” to remember that the variable on the left hand side gets or is assigned the value on the right. In the figure above, score is assigned the value of 10 times points (which is another variable) plus 5.

The following video by Dr. Colleen Lewis shows how variables can change values in memory using assignment statements.

As we saw in the video, we can set one variable to a copy of the value of another variable like y = x;. This won’t change the value of the variable that you are copying from.

coding exercise

Click on the Show CodeLens button to step through the code and see how the values of the variables change.

The program is supposed to figure out the total money value given the number of dimes, quarters and nickels. There is an error in the calculation of the total. Fix the error to compute the correct amount.

Calculate and print the total pay given the weekly salary and the number of weeks worked. Use string concatenation with the totalPay variable to produce the output Total Pay = $3000 . Don’t hardcode the number 3000 in your print statement.

exercise

Assume you have a package with a given height 3 inches and width 5 inches. If the package is rotated 90 degrees, you should swap the values for the height and width. The code below makes an attempt to swap the values stored in two variables h and w, which represent height and width. Variable h should end up with w’s initial value of 5 and w should get h’s initial value of 3. Unfortunately this code has an error and does not work. Use the CodeLens to step through the code to understand why it fails to swap the values in h and w.

1-4-7: Explain in your own words why the ErrorSwap program code does not swap the values stored in h and w.

Swapping two variables requires a third variable. Before assigning h = w , you need to store the original value of h in the temporary variable. In the mixed up programs below, drag the blocks to the right to put them in the right order.

The following has the correct code that uses a third variable named “temp” to swap the values in h and w.

The code is mixed up and contains one extra block which is not needed in a correct solution. Drag the needed blocks from the left into the correct order on the right, then check your solution. You will be told if any of the blocks are in the wrong order or if you need to remove one or more blocks.

After three incorrect attempts you will be able to use the Help Me button to make the problem easier.

Fix the code below to perform a correct swap of h and w. You need to add a new variable named temp to use for the swap.

1.4.2. Incrementing the value of a variable ¶

If you use a variable to keep score you would probably increment it (add one to the current value) whenever score should go up. You can do this by setting the variable to the current value of the variable plus one (score = score + 1) as shown below. The formula looks a little crazy in math class, but it makes sense in coding because the variable on the left is set to the value of the arithmetic expression on the right. So, the score variable is set to the previous value of score + 1.

Click on the Show CodeLens button to step through the code and see how the score value changes.

1-4-11: What is the value of b after the following code executes?

  • It sets the value for the variable on the left to the value from evaluating the right side. What is 5 * 2?
  • Correct. 5 * 2 is 10.

1-4-12: What are the values of x, y, and z after the following code executes?

  • x = 0, y = 1, z = 2
  • These are the initial values in the variable, but the values are changed.
  • x = 1, y = 2, z = 3
  • x changes to y's initial value, y's value is doubled, and z is set to 3
  • x = 2, y = 2, z = 3
  • Remember that the equal sign doesn't mean that the two sides are equal. It sets the value for the variable on the left to the value from evaluating the right side.
  • x = 1, y = 0, z = 3

1.4.3. Operators ¶

Java uses the standard mathematical operators for addition ( + ), subtraction ( - ), multiplication ( * ), and division ( / ). Arithmetic expressions can be of type int or double. An arithmetic operation that uses two int values will evaluate to an int value. An arithmetic operation that uses at least one double value will evaluate to a double value. (You may have noticed that + was also used to put text together in the input program above – more on this when we talk about strings.)

Java uses the operator == to test if the value on the left is equal to the value on the right and != to test if two items are not equal. Don’t get one equal sign = confused with two equal signs == ! They mean different things in Java. One equal sign is used to assign a value to a variable. Two equal signs are used to test a variable to see if it is a certain value and that returns true or false as you’ll see below. Use == and != only with int values and not doubles because double values are an approximation and 3.3333 will not equal 3.3334 even though they are very close.

Run the code below to see all the operators in action. Do all of those operators do what you expected? What about 2 / 3 ? Isn’t surprising that it prints 0 ? See the note below.

When Java sees you doing integer division (or any operation with integers) it assumes you want an integer result so it throws away anything after the decimal point in the answer, essentially rounding down the answer to a whole number. If you need a double answer, you should make at least one of the values in the expression a double like 2.0.

With division, another thing to watch out for is dividing by 0. An attempt to divide an integer by zero will result in an ArithmeticException error message. Try it in one of the active code windows above.

Operators can be used to create compound expressions with more than one operator. You can either use a literal value which is a fixed value like 2, or variables in them. When compound expressions are evaluated, operator precedence rules are used, so that *, /, and % are done before + and -. However, anything in parentheses is done first. It doesn’t hurt to put in extra parentheses if you are unsure as to what will be done first.

In the example below, try to guess what it will print out and then run it to see if you are right. Remember to consider operator precedence .

1-4-15: Consider the following code segment. Be careful about integer division.

What is printed when the code segment is executed?

  • 0.666666666666667
  • Don't forget that division and multiplication will be done first due to operator precedence.
  • Yes, this is equivalent to (5 + ((a/b)*c) - 1).
  • Don't forget that division and multiplication will be done first due to operator precedence, and that an int/int gives an int result where it is rounded down to the nearest int.

1-4-16: Consider the following code segment.

What is the value of the expression?

  • Dividing an integer by an integer results in an integer
  • Correct. Dividing an integer by an integer results in an integer
  • The value 5.5 will be rounded down to 5

1-4-17: Consider the following code segment.

  • Correct. Dividing a double by an integer results in a double
  • Dividing a double by an integer results in a double

1-4-18: Consider the following code segment.

  • Correct. Dividing an integer by an double results in a double
  • Dividing an integer by an double results in a double

1.4.4. The Modulo Operator ¶

The percent sign operator ( % ) is the mod (modulo) or remainder operator. The mod operator ( x % y ) returns the remainder after you divide x (first number) by y (second number) so 5 % 2 will return 1 since 2 goes into 5 two times with a remainder of 1. Remember long division when you had to specify how many times one number went into another evenly and the remainder? That remainder is what is returned by the modulo operator.

../_images/mod-py.png

Figure 2: Long division showing the whole number result and the remainder ¶

In the example below, try to guess what it will print out and then run it to see if you are right.

The result of x % y when x is smaller than y is always x . The value y can’t go into x at all (goes in 0 times), since x is smaller than y , so the result is just x . So if you see 2 % 3 the result is 2 .

1-4-21: What is the result of 158 % 10?

  • This would be the result of 158 divided by 10. modulo gives you the remainder.
  • modulo gives you the remainder after the division.
  • When you divide 158 by 10 you get a remainder of 8.

1-4-22: What is the result of 3 % 8?

  • 8 goes into 3 no times so the remainder is 3. The remainder of a smaller number divided by a larger number is always the smaller number!
  • This would be the remainder if the question was 8 % 3 but here we are asking for the reminder after we divide 3 by 8.
  • What is the remainder after you divide 3 by 8?

1.4.5. FlowCharting ¶

Assume you have 16 pieces of pizza and 5 people. If everyone gets the same number of slices, how many slices does each person get? Are there any leftover pieces?

In industry, a flowchart is used to describe a process through symbols and text. A flowchart usually does not show variable declarations, but it can show assignment statements (drawn as rectangle) and output statements (drawn as rhomboid).

The flowchart in figure 3 shows a process to compute the fair distribution of pizza slices among a number of people. The process relies on integer division to determine slices per person, and the mod operator to determine remaining slices.

Flow Chart

Figure 3: Example Flow Chart ¶

A flowchart shows pseudo-code, which is like Java but not exactly the same. Syntactic details like semi-colons are omitted, and input and output is described in abstract terms.

Complete the program based on the process shown in the Figure 3 flowchart. Note the first line of code declares all 4 variables as type int. Add assignment statements and print statements to compute and print the slices per person and leftover slices. Use System.out.println for output.

1.4.6. Storing User Input in Variables ¶

Variables are a powerful abstraction in programming because the same algorithm can be used with different input values saved in variables.

Program input and output

Figure 4: Program input and output ¶

A Java program can ask the user to type in one or more values. The Java class Scanner is used to read from the keyboard input stream, which is referenced by System.in . Normally the keyboard input is typed into a console window, but since this is running in a browser you will type in a small textbox window displayed below the code. The code below shows an example of prompting the user to enter a name and then printing a greeting. The code String name = scan.nextLine() gets the string value you enter as program input and then stores the value in a variable.

Run the program a few times, typing in a different name. The code works for any name: behold, the power of variables!

Run this program to read in a name from the input stream. You can type a different name in the input window shown below the code.

Try stepping through the code with the CodeLens tool to see how the name variable is assigned to the value read by the scanner. You will have to click “Hide CodeLens” and then “Show in CodeLens” to enter a different name for input.

The Scanner class has several useful methods for reading user input. A token is a sequence of characters separated by white space.

Run this program to read in an integer from the input stream. You can type a different integer value in the input window shown below the code.

A rhomboid (slanted rectangle) is used in a flowchart to depict data flowing into and out of a program. The previous flowchart in Figure 3 used a rhomboid to indicate program output. A rhomboid is also used to denote reading a value from the input stream.

Flow Chart

Figure 5: Flow Chart Reading User Input ¶

Figure 5 contains an updated version of the pizza calculator process. The first two steps have been altered to initialize the pizzaSlices and numPeople variables by reading two values from the input stream. In Java this will be done using a Scanner object and reading from System.in.

Complete the program based on the process shown in the Figure 5 flowchart. The program should scan two integer values to initialize pizzaSlices and numPeople. Run the program a few times to experiment with different values for input. What happens if you enter 0 for the number of people? The program will bomb due to division by zero! We will see how to prevent this in a later lesson.

The program below reads two integer values from the input stream and attempts to print the sum. Unfortunately there is a problem with the last line of code that prints the sum.

Run the program and look at the result. When the input is 5 and 7 , the output is Sum is 57 . Both of the + operators in the print statement are performing string concatenation. While the first + operator should perform string concatenation, the second + operator should perform addition. You can force the second + operator to perform addition by putting the arithmetic expression in parentheses ( num1 + num2 ) .

More information on using the Scanner class can be found here https://www.w3schools.com/java/java_user_input.asp

1.4.7. Programming Challenge : Dog Years ¶

In this programming challenge, you will calculate your age, and your pet’s age from your birthdates, and your pet’s age in dog years. In the code below, type in the current year, the year you were born, the year your dog or cat was born (if you don’t have one, make one up!) in the variables below. Then write formulas in assignment statements to calculate how old you are, how old your dog or cat is, and how old they are in dog years which is 7 times a human year. Finally, print it all out.

Calculate your age and your pet’s age from the birthdates, and then your pet’s age in dog years. If you want an extra challenge, try reading the values using a Scanner.

1.4.8. Summary ¶

Arithmetic expressions include expressions of type int and double.

The arithmetic operators consist of +, -, * , /, and % (modulo for the remainder in division).

An arithmetic operation that uses two int values will evaluate to an int value. With integer division, any decimal part in the result will be thrown away, essentially rounding down the answer to a whole number.

An arithmetic operation that uses at least one double value will evaluate to a double value.

Operators can be used to construct compound expressions.

During evaluation, operands are associated with operators according to operator precedence to determine how they are grouped. (*, /, % have precedence over + and -, unless parentheses are used to group those.)

An attempt to divide an integer by zero will result in an ArithmeticException to occur.

The assignment operator (=) allows a program to initialize or change the value stored in a variable. The value of the expression on the right is stored in the variable on the left.

During execution, expressions are evaluated to produce a single value.

The value of an expression has a type based on the evaluation of the expression.

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Variables in Java

In this lesson, we will explore the concept of variables in Java. A variable is a container that holds values that are used in a Java program. Every variable is assigned a data type, which tells the compiler what type of data the variable can hold.

In this module, we will cover:

Variable declaration: We will discuss how to declare variables in Java, and why it's necessary.

Java data types :

We will delve into the different data types available in Java, such as

integers (int),

floating-point numbers (float and double),

characters (char),

and booleans (boolean).

Assigning values to variables :

We will explain how to assign values to declared variables and how you can change these values later in your program.

Understanding and using operators :

We will discuss how to use basic operators in Java, such as

addition (+),

subtraction (-),

multiplication (*),

division (/),

and the modulus operator (%) ,

to manipulate the values in variables.

Creating your own variables :

At the end of the lesson, we'll put what you've learned into practice and guide you through creating your own variables and using them in simple mathematical operations.

Remember, variables are one of the foundational concepts of programming, so gaining a strong understanding of them is crucial as you continue your Java learning journey.

Java Variables Example

In this example, we're going to create some variables, assign values to them, and perform a simple operation.

When you run this program, it will print:

The sum of x and y is: 30.

Understanding the Code:

int x; and int y;:

Here we're declaring two integer variables, x and y. At this point, they don't have a value yet.

x = 10; and y = 20;:

Here we're assigning the values 10 and 20 to the variables x and y, respectively.

int result = x + y;:

Here we're declaring a new integer variable called result and assigning it the sum of x and y.

System.out.println("The sum of x and y is: " + result);: Finally, we're printing the result to the console.

Exercise for you

Variable Declaration and Assigning Values:

Declare variables of each data type mentioned (int, float, double, char, boolean) and assign them values. Then, print each of the variables.

int myInteger = 10; float myFloat = 20.5f; double myDouble = 30.25; char myChar = 'A'; boolean myBoolean = true;

System.out.println(myInteger); System.out.println(myFloat); System.out.println(myDouble); System.out.println(myChar); System.out.println(myBoolean);

Changing Values of Variables:

Change the values of the variables you have declared above and print them again.

myInteger = 15; myFloat = 25.5f; myDouble = 35.25; myChar = 'B'; myBoolean = false;

Basic Operations with Variable s:

Use the basic operators to perform mathematical operations using the variables you have declared. Print the results.

int num1 = 10; int num2 = 5;

int sum = num1 + num2; int difference = num1 - num2; int product = num1 * num2; double quotient = (double) num1 / num2; int remainder = num1 % num2;

System.out.println("Sum: " + sum); System.out.println("Difference: " + difference); System.out.println("Product: " + product); System.out.println("Quotient: " + quotient); System.out.println("Remainder: " + remainder);

Remember, these exercises are just to get you started. You should try to create more complex programs using these concepts to deepen your understanding. Happy coding!

Java Operators and Type Conversion

In this lesson, we're going to explore Java operators and learn about type conversion. Operators allow us to perform different operations on variables such as arithmetic, comparison, logical, and more. Type conversion, also known as type casting, is a way of changing an entity from one data type to another.

Here's what we will cover:

Arithmetic Operators : We will start with the basic arithmetic operators like addition (+), subtraction (-), multiplication (*), division (/), and modulus (%).

Comparison Operators : Next, we'll learn about comparison operators. These include equal to (==), not equal to (!=), greater than (>), less than (<), greater than or equal to (>=), and less than or equal to (<=).

Logical Operators : We'll delve into logical operators like AND (&&), OR (||), and NOT (!) and learn how they can be used to form more complex boolean expressions.

Type Conversion : Lastly, we'll discuss type conversion in Java. We'll learn the difference between implicit and explicit conversion, and when to use each.

By the end of this lesson, you should have a good understanding of how to use operators in Java and how to convert between different data types

Java Operators and Type Conversion Example

In this example, we're going to create some variables and perform operations using Java operators. We'll also demonstrate type conversion.

------------------------------------------------------------------------------

public class OperatorsExample { public static void main(String[] args) { // Declare two integer variables int x = 10; int y = 20; // Use of arithmetic operator int sum = x + y; System.out.println("The sum of x and y is: " + sum); // Use of comparison operator boolean compare = x > y; System.out.println("Is x greater than y? " + compare); // Use of logical operator boolean logical = (x > 5) && (y > 15); System.out.println("Is x greater than 5 AND y greater than 15? " + logical); // Type conversion double z = (double) x; System.out.println("The value of x as a double is: " + z); } }

When you run this program, it will output:

The sum of x and y is: 30 Is x greater than y? false Is x greater than 5 AND y greater than 15? true The value of x as a double is: 10.0

Understanding the Code :

  • The first section declares two integer variables, x and y, and assigns them the values 10 and 20 , respectively.
  • We then use the arithmetic + operator to calculate the sum of x and y .
  • The > comparison operator is used to check if x is greater than y .
  • We then use the logical && operator to check if both x > 5 and y > 15 are true.
  • Finally, we convert the integer x to a double using type casting (double) x .
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Java Variable Types

Java variable declaration, java variable assignment, java variable reading, java variable naming conventions, java local-variable type inference.

A Java variable is a piece of memory that can contain a data value. A variable thus has a data type. Data types are covered in more detail in the text on Java data types .

Variables are typically used to store information which your Java program needs to do its job. This can be any kind of information ranging from texts, codes (e.g. country codes, currency codes etc.) to numbers, temporary results of multi step calculations etc.

In the code example below, the main() method contains the declaration of a single integer variable named number . The value of the integer variable is first set to 10, and then 20 is added to the variable afterwards.

In Java there are four types of variables:

  • Non-static fields
  • Static fields
  • Local variables

A non-static field is a variable that belongs to an object. Objects keep their internal state in non-static fields. Non-static fields are also called instance variables, because they belong to instances (objects) of a class. Non-static fields are covered in more detail in the text on Java fields .

A static field is a variable that belongs to a class. A static field has the same value for all objects that access it. Static fields are also called class variables. Static fields are also covered in more detail in the text on Java fields .

A local variable is a variable declared inside a method. A local variable is only accessible inside the method that declared it. Local variables are covered in more detail in the text on Java methods .

A parameter is a variable that is passed to a method when the method is called. Parameters are also only accessible inside the method that declares them, although a value is assigned to them when the method is called. Parameters are also covered in more detail in the text on Java methods .

Exactly how a variable is declared depends on what type of variable it is (non-static, static, local, parameter). However, there are certain similarities that

In Java you declare a variable like this:

Instead of the word type , you write the data type of the variable. Similarly, instead of the word name you write the name you want the variable to have.

Here is an example declaring a variable named myVariable of type int .

Here are examples of how to declare variables of all the primitive data types in Java:

Here are examples of how to declare variables of the object types in Java:

Notice the uppercase first letter of the object types.

When a variable points to an object the variable is called a "reference" to an object. I will get back to the difference between primitive variable values and object references in a later text.

The rules and conventions for choosing variable names are covered later in this text.

Assigning a value to a variable in Java follows this pattern:

Here are three concrete examples which assign values to three different variables with different data types

The first line assigns the byte value 127 to the byte variable named myByte . The second line assigns the floating point value 199.99 to the floating point variable named myFloat . The third line assigns the String value (text) this is a text to the String variable named myString .

You can also assign a value to a variable already when it is declared. Here is how that is done:

You can read the value of a Java variable by writing its name anywhere a variable or constant variable can be used in the code. For instance, as the right side of a variable assignment, as parameter to a method call, or inside a arithmetic expression. For instance:

There are a few rules and conventions related to the naming of variables.

The rules are:

  • Java variable names are case sensitive. The variable name money is not the same as Money or MONEY .
  • Java variable names must start with a letter, or the $ or _ character.
  • After the first character in a Java variable name, the name can also contain numbers (in addition to letters, the $, and the _ character).
  • Variable names cannot be equal to reserved key words in Java. For instance, the words int or for are reserved words in Java. Therefore you cannot name your variables int or for .

Here are a few valid Java variable name examples:

There are also a few Java variable naming conventions. These conventions are not necessary to follow. The compiler to not enforce them. However, many Java developers are used to these naming conventions. Therefore it will be easier for them to read your Java code if you follow them too, and easier for you to read the code of other Java developers if you are used to these naming conventions. The conventions are:

  • Variable names are written in lowercase. For instance, variable or apple .
  • If variable names consist of multiple words, each word after the first word has its first letter written in uppercase. For instance, variableName or bigApple .
  • Even though it is allowed, you do not normally start a Java variable name with $ or _ .
  • Static final fields (constants) are named in all uppercase, typically using an _ to separate the words in the name. For instance EXCHANGE_RATE or COEFFICIENT .

From Java 10 it is possible to have the Java compiler infer the type of a local variable by looking at what actual type that is assigned to the variable when the variable is declared. This enhancement is restricted to local variables, indexes in for-each loops and local variables declared in for-loops.

To see how the Java local-variable type inference works, here is first an example of a pre Java 10 String variable declaration:

From Java 10 it is no longer necessary to specify the type of the variable when declared, if the type can be inferred from the value assigned to the variable. Here is an example of declaring a variable in Java 10 using local-variable type inference:

Notice the var keyword used in front of the variable name, instead of the type String . The compiler can see from the value assigned that the type of the variable should be String , so you don't have to write it explicitly.

Here are a few additional Java local-variable type inference examples:

Java ForkJoinPool

The Java Tutorials have been written for JDK 8. Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available. See Java Language Changes for a summary of updated language features in Java SE 9 and subsequent releases. See JDK Release Notes for information about new features, enhancements, and removed or deprecated options for all JDK releases.

Declaring Member Variables

There are several kinds of variables:

  • Member variables in a class—these are called fields .
  • Variables in a method or block of code—these are called local variables .
  • Variables in method declarations—these are called parameters .

The Bicycle class uses the following lines of code to define its fields:

Field declarations are composed of three components, in order:

  • Zero or more modifiers, such as public or private .
  • The field's type.
  • The field's name.

The fields of Bicycle are named cadence , gear , and speed and are all of data type integer ( int ). The public keyword identifies these fields as public members, accessible by any object that can access the class.

Access Modifiers

The first (left-most) modifier used lets you control what other classes have access to a member field. For the moment, consider only public and private . Other access modifiers will be discussed later.

  • public modifier—the field is accessible from all classes.
  • private modifier—the field is accessible only within its own class.

In the spirit of encapsulation, it is common to make fields private. This means that they can only be directly accessed from the Bicycle class. We still need access to these values, however. This can be done indirectly by adding public methods that obtain the field values for us:

All variables must have a type. You can use primitive types such as int , float , boolean , etc. Or you can use reference types, such as strings, arrays, or objects.

Variable Names

All variables, whether they are fields, local variables, or parameters, follow the same naming rules and conventions that were covered in the Language Basics lesson, Variables—Naming .

In this lesson, be aware that the same naming rules and conventions are used for method and class names, except that

  • the first letter of a class name should be capitalized, and
  • the first (or only) word in a method name should be a verb.

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1.7 Java | Assignment Statements & Expressions

An assignment statement designates a value for a variable. An assignment statement can be used as an expression in Java.

After a variable is declared, you can assign a value to it by using an assignment statement . In Java, the equal sign = is used as the assignment operator . The syntax for assignment statements is as follows:

An expression represents a computation involving values, variables, and operators that, when taking them together, evaluates to a value. For example, consider the following code:

You can use a variable in an expression. A variable can also be used on both sides of the =  operator. For example:

In the above assignment statement, the result of x + 1  is assigned to the variable x . Let’s say that x is 1 before the statement is executed, and so becomes 2 after the statement execution.

To assign a value to a variable, you must place the variable name to the left of the assignment operator. Thus the following statement is wrong:

Note that the math equation  x = 2 * x + 1  ≠ the Java expression x = 2 * x + 1

Java Assignment Statement vs Assignment Expression

Which is equivalent to:

And this statement

is equivalent to:

Note: The data type of a variable on the left must be compatible with the data type of a value on the right. For example, int x = 1.0 would be illegal, because the data type of x is int (integer) and does not accept the double value 1.0 without Type Casting .

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How to assign a value to a variable in java.

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The assigning of a value to a variable is carried out with the help of the "=" symbol.   Consider the following examples:

Example No.1

Let’s say we want to assign the value of "10" to the variable "k" of the "int" type. It’s very easy and can be done in two ways:

If you try to run this code on your computer, you will see the following:

In this example, we first declared the variable to be "k" of the "int" type:

Then in another line we assigned the value "10" to the variable "k":

As you you may have understood from the example, the "=" symbol is an assignment operation. It always works from right to left:

Variables Announement Vertex Academy

This assigns the value "10" to the variable "k."

As you can see, in this example we declared the variable as "k" of the int type and assigned the value to it in a single line:

int k = 10;

So, now you know that:

  • The "=" symbol is responsible for assignment operation and we assign values to variables with the help of this symbol.
  • There are two ways to assign a value to variables: in one line or in two lines.

What is variable initialization?

Actually, you already know what it is. Initialization is the assignment of an initial value to a variable. In other words, if you just created a variable and didn’t assign any value to it, then this variable is uninitialized. So, if you ever hear:

  • “We need to initialize the variable,” it simply means that “we need to assign the initial value to the variable.”
  • “The variable has been initialized,” it simply means that “we have assigned the initial value to the variable.”

Here's another example of variable initialization:

Example No.2

15 100 100000000 I love Java M 145.34567 3.14 true

In this line, we declared variable number1 of the byte type and, with the help of the "=" symbol, assigned the value 15 to it.

In this line, we declared variable number2 of the short type and, with the help of the "=" symbol, assigned the value 100 to it.

In this line, we declared variable number3 of the long type and, with the help of the "=" symbol, assigned the value 100000000 to it.

In this line, we declared the variable title of the string type and, with the help of the "=" symbol, assigned the value “I love Java” to it. Since this variable belongs to the string type, we wrote the value of the variable in double quotes .

In this line, we declared the variable letter of the char type and, with the help of the "=" symbol, assigned the value “M” to it. Note that since the variable belongs to the char type, we wrote the value of the variable in single quotes .

In this line, we declared the variable sum of the double type and, with the help of the "=" symbol, assigned the value "145.34567" to it.

In this line, we declared the variable pi of the float type and, with the help of the "=" symbol, assigned the value “3.14f” to it. Note that we added f to the number 3.14. This is a small detail that you'll need to remember: it's necessary to add f to the values of float variables.  However, when you see it in the console, it will show up as just 3.14 (without the "f").

In this line, we declared the variable result of the boolean type and, with the help of the "=" symbol, assigned the value "true" to it.

Then we display the values of all the variables in the console with the help of

LET’S SUMMARIZE:

  • We assign a value to a variable with the help of the assignment operator "=." It always works from right to left.

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2. There are two ways to assign a value to a variable:

  • in two lines
  • or in one line
  • You also need to remember:

If we assign a value to a variable of the string type, we need to put it in double quotes :

If we assign a value to a variable of the char type, we need to put it in single quotes :

If we assign a value to a variable of the float type, we need to  add the letter "f" :

  • "Initialization" means “to assign an initial value to a variable.”

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Operators are symbols that perform operations on variables and values. For example, + is an operator used for addition, while * is also an operator used for multiplication.

Operators in Java can be classified into 5 types:

  • Arithmetic Operators
  • Assignment Operators
  • Relational Operators
  • Logical Operators
  • Unary Operators
  • Bitwise Operators

1. Java Arithmetic Operators

Arithmetic operators are used to perform arithmetic operations on variables and data. For example,

Here, the + operator is used to add two variables a and b . Similarly, there are various other arithmetic operators in Java.

Example 1: Arithmetic Operators

In the above example, we have used + , - , and * operators to compute addition, subtraction, and multiplication operations.

/ Division Operator

Note the operation, a / b in our program. The / operator is the division operator.

If we use the division operator with two integers, then the resulting quotient will also be an integer. And, if one of the operands is a floating-point number, we will get the result will also be in floating-point.

% Modulo Operator

The modulo operator % computes the remainder. When a = 7 is divided by b = 4 , the remainder is 3 .

Note : The % operator is mainly used with integers.

2. Java Assignment Operators

Assignment operators are used in Java to assign values to variables. For example,

Here, = is the assignment operator. It assigns the value on its right to the variable on its left. That is, 5 is assigned to the variable age .

Let's see some more assignment operators available in Java.

Example 2: Assignment Operators

3. java relational operators.

Relational operators are used to check the relationship between two operands. For example,

Here, < operator is the relational operator. It checks if a is less than b or not.

It returns either true or false .

Example 3: Relational Operators

Note : Relational operators are used in decision making and loops.

4. Java Logical Operators

Logical operators are used to check whether an expression is true or false . They are used in decision making.

Example 4: Logical Operators

Working of Program

  • (5 > 3) && (8 > 5) returns true because both (5 > 3) and (8 > 5) are true .
  • (5 > 3) && (8 < 5) returns false because the expression (8 < 5) is false .
  • (5 < 3) || (8 > 5) returns true because the expression (8 > 5) is true .
  • (5 > 3) || (8 < 5) returns true because the expression (5 > 3) is true .
  • (5 < 3) || (8 < 5) returns false because both (5 < 3) and (8 < 5) are false .
  • !(5 == 3) returns true because 5 == 3 is false .
  • !(5 > 3) returns false because 5 > 3 is true .

5. Java Unary Operators

Unary operators are used with only one operand. For example, ++ is a unary operator that increases the value of a variable by 1 . That is, ++5 will return 6 .

Different types of unary operators are:

  • Increment and Decrement Operators

Java also provides increment and decrement operators: ++ and -- respectively. ++ increases the value of the operand by 1 , while -- decrease it by 1 . For example,

Here, the value of num gets increased to 6 from its initial value of 5 .

Example 5: Increment and Decrement Operators

In the above program, we have used the ++ and -- operator as prefixes (++a, --b) . We can also use these operators as postfix (a++, b++) .

There is a slight difference when these operators are used as prefix versus when they are used as a postfix.

To learn more about these operators, visit increment and decrement operators .

6. Java Bitwise Operators

Bitwise operators in Java are used to perform operations on individual bits. For example,

Here, ~ is a bitwise operator. It inverts the value of each bit ( 0 to 1 and 1 to 0 ).

The various bitwise operators present in Java are:

These operators are not generally used in Java. To learn more, visit Java Bitwise and Bit Shift Operators .

Other operators

Besides these operators, there are other additional operators in Java.

The instanceof operator checks whether an object is an instanceof a particular class. For example,

Here, str is an instance of the String class. Hence, the instanceof operator returns true . To learn more, visit Java instanceof .

The ternary operator (conditional operator) is shorthand for the if-then-else statement. For example,

Here's how it works.

  • If the Expression is true , expression1 is assigned to the variable .
  • If the Expression is false , expression2 is assigned to the variable .

Let's see an example of a ternary operator.

In the above example, we have used the ternary operator to check if the year is a leap year or not. To learn more, visit the Java ternary operator .

Now that you know about Java operators, it's time to know about the order in which operators are evaluated. To learn more, visit Java Operator Precedence .

Table of Contents

  • Introduction
  • Java Arithmetic Operators
  • Java Assignment Operators
  • Java Relational Operators
  • Java Logical Operators
  • Java Unary Operators
  • Java Bitwise Operators

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variables assignment in java

7 Best Java Homework Help Websites: How to Choose Your Perfect Match?

J ava programming is not a field that could be comprehended that easily; thus, it is no surprise that young learners are in search of programming experts to get help with Java homework and handle their assignments. But how to choose the best alternative when the number of proposals is enormous? 

In this article, we are going to talk about the top ‘do my Java assignment’ services that offer Java assignment assistance and dwell upon their features. In the end, based on the results, you will be able to choose the one that meets your demands to the fullest and answer your needs. Here is the list of services that are available today, as well as those that are on everyone's lips:

TOP Java Assignment Help Services: What Makes Them Special?

No need to say that every person is an individual and the thing that suits a particular person could not meet the requirements of another. So, how can we name the best Java assignment help services on the web? - We have collected the top issues students face when searching for Java homework help and found the companies that promise to meet these requirements. 

What are these issues, though?

  • Pricing . Students are always pressed for budget, and finding services that suit their pockets is vital. Thus, we tried to provide services that are relatively affordable on the market. Of course, professional services can’t be offered too cheaply, so we have chosen the ones that balance professionalism and affordability.
  • Programming languages . Not all companies have experts in all possible programming languages. Thus, we tried to choose the ones that offer as many different languages as possible. 
  • Expert staff . In most cases, students come to a company when they need to place their ‘do my Java homework’ orders ASAP. Thus, a large expert staff is a real benefit for young learners. They want to come to a service, place their order and get a professional to start working on their project in no time. 
  • Reviews . Of course, everyone wants to get professional help with Java homework from a reputable company that has already completed hundreds of Java assignments for their clients. Thus, we have mentioned only those companies that have earned enough positive feedback from their clients.
  • Deadline options. Flexible deadline options are also a benefit for those who are placing their last-minute Java homework help assignments. Well, we also provide services with the most extended deadlines for those who want to save some money and place their projects beforehand.
  • Guarantees . This is the must-feature if you want to get quality assistance and stay assured you are totally safe with the company you have chosen. In our list, we have only named companies that provide client-oriented guarantees and always keep their word, as well as offer only professional Java assignment experts.
  • Customization . Every service from the list offers Java assistance tailored to clients’ personal needs. There, you won’t find companies that offer pre-completed projects and sell them at half-price.

So, let’s have a closer look at each option so you can choose the one that totally meets your needs.

DoMyAssignments.com

At company service, you can get assistance with academic writing as well as STEM projects. The languages you can get help with are C#, C++, Computer science, Java, Javascript, HTML, PHP, Python, Ruby, and SQL.

The company’s prices start at $30/page for a project that needs to be done in 14+ days.

Guarantees and extra services

The company offers a list of guarantees to make your cooperation as comfortable as possible. So, what can you expect from the service?

  • Free revisions . When you get your order, you can ask your expert for revisions if needed. It means that if you see that any of your demands were missed, you can get revisions absolutely for free. 
  • Money-back guarantee. The company offers professional help, and they are sure about their experts and the quality of their assistance. Still, if you receive a project that does not meet your needs, you can ask for a full refund. 
  • Confidentiality guarantee . Stay assured that all your personal information is safe and secure, as the company scripts all the information you share with them.
  • 100% customized assistance . At this service, you won’t find pre-written codes, all the projects are completed from scratch.

Expert staff

If you want to hire one of the top Java homework experts at DoMyAssignments , you can have a look at their profile, see the latest orders they have completed, and make sure they are the best match for your needs. Also, you can have a look at the samples presented on their website and see how professional their experts are. If you want to hire a professional who completed a particular sample project, you can also turn to a support team and ask if you can fire this expert.

CodingHomeworkHelp.org

CodingHomeworkHelp is rated at 9.61/10 and has 10+ years of experience in the programming assisting field. Here, you can get help with the following coding assignments: MatLab, Computer Science, Java, HTML, C++, Python, R Studio, PHP, JavaScript, and C#.

Free options all clients get

Ordering your project with CodingHomeworkHelp.org, you are to enjoy some other options that will definitely satisfy you.

  • Partial payments . If you order a large project, you can pay for it in two parts. Order the first one, get it done, and only then pay for the second one.
  • Revisions . As soon as you get your order, you can ask for endless revisions unless your project meets your initial requirements.
  • Chat with your expert . When you place your order, you get an opportunity to chat directly with your coding helper. If you have any questions or demands, there is no need to first contact the support team and ask them to contact you to your assistant. 
  • Code comments . If you have questions concerning your code, you can ask your helper to provide you with the comments that will help you better understand it and be ready to discuss your project with your professor.

The prices start at $20/page if you set a 10+ days deadline. But, with CodingHomeworkHelp.org, you can get a special discount; you can take 20% off your project when registering on the website. That is a really beneficial option that everyone can use.

CWAssignments.com

CWAssignments.com is an assignment helper where you can get professional help with programming and calculations starting at $30/page. Moreover, you can get 20% off your first order.

Working with the company, you are in the right hands and can stay assured that the final draft will definitely be tailored to your needs. How do CWAssignments guarantee their proficiency?

  • Money-back guarantee . If you are not satisfied with the final work, if it does not meet your expectations, you can request a refund. 
  • Privacy policy . The service collects only the data essential to complete your order to make your cooperation effective and legal. 
  • Security payment system . All the transactions are safe and encrypted to make your personal information secure. 
  • No AI-generated content . The company does not use any AI tools to complete their orders. When you get your order, you can even ask for the AI detection report to see that your assignment is pure. 

With CWAssignments , you can regulate the final cost of your project. As it was mentioned earlier, the prices start at $30/page, but if you set a long-term deadline or ask for help with a Java assignment or with a part of your task, you can save a tidy sum.

DoMyCoding.com

This company has been offering its services on the market for 18+ years and provides assistance with 30+ programming languages, among which are Python, Java, C / C++ / C#, JavaScript, HTML, SQL, etc. Moreover, here, you can get assistance not only with programming but also with calculations. 

Pricing and deadlines

With DoMyCoding , you can get help with Java assignments in 8 hours, and their prices start at $30/page with a 14-day deadline.

Guarantees and extra benefits

The service offers a number of guarantees that protect you from getting assistance that does not meet your requirements. Among the guarantees, you can find:

  • The money-back guarantee . If your order does not meet your requirements, you will get a full refund of your order.
  • Free edits within 7 days . After you get your project, you can request any changes within the 7-day term. 
  • Payments in parts . If you have a large order, you can pay for it in installments. In this case, you get a part of your order, check if it suits your needs, and then pay for the other part. 
  • 24/7 support . The service operates 24/7 to answer your questions as well as start working on your projects. Do not hesitate to use this option if you need to place an ASAP order.
  • Confidentiality guarantee . The company uses the most secure means to get your payments and protects the personal information you share on the website to the fullest.

More benefits

Here, we also want to pay your attention to the ‘Samples’ section on the website. If you are wondering if a company can handle your assignment or you simply want to make sure they are professionals, have a look at their samples and get answers to your questions. 

AssignCode.com

AssignCode is one of the best Java assignment help services that you can entrust with programming, mathematics, biology, engineering, physics, and chemistry. A large professional staff makes this service available to everyone who needs help with one of these disciplines. As with some of the previous companies, AssignCode.com has reviews on different platforms (Reviews.io and Sitejabber) that can help you make your choice. 

As with all the reputed services, AssignCode offers guarantees that make their cooperation with clients trustworthy and comfortable. Thus, the company guarantees your satisfaction, confidentiality, client-oriented attitude, and authenticity.

Special offers

Although the company does not offer special prices on an ongoing basis, regular clients can benefit from coupons the service sends them via email. Thus, if you have already worked with the company, make sure to check your email before placing a new one; maybe you have received a special offer that will help you save some cash.

AssignmentShark.com

Reviews about this company you can see on different platforms. Among them are Reviews.io (4.9 out of 5), Sitejabber (4.5 points), and, of course, their own website (9.6 out of 10). The rate of the website speaks for itself.

Pricing 

When you place your ‘do my Java homework’ request with AssignmentShark , you are to pay $20/page for the project that needs to be done in at least ten days. Of course, if the due date is closer, the cost will differ. All the prices are presented on the website so that you can come, input all the needed information, and get an approximate calculation.

Professional staff

On the ‘Our experts’ page, you can see the full list of experts. Or, you can use filters to see the professional in the required field. 

The company has a quick form on its website for those who want to join their professional staff, which means that they are always in search of new experts to make sure they can provide clients with assistance as soon as the need arises.

Moreover, if one wants to make sure the company offers professional assistance, one can have a look at the latest orders and see how experts provide solutions to clients’ orders.

What do clients get?

Placing orders with the company, one gets a list of inclusive services:

  • Free revisions. You can ask for endless revisions until your order fully meets your demands.
  • Code comments . Ask your professional to provide comments on the codes in order to understand your project perfectly. 
  • Source files . If you need the list of references and source files your helper turned to, just ask them to add these to the project.
  • Chat with the professional. All the issues can be solved directly with your coding assistant.
  • Payment in parts. Large projects can be paid for in parts. When placing your order, let your manager know that you want to pay in parts.

ProgrammingDoer.com

ProgrammingDoer is one more service that offers Java programming help to young learners and has earned a good reputation among previous clients. 

The company cherishes its reputation and does its best to let everyone know about their proficiency. Thus, you, as a client, can read what people think about the company on several platforms - on their website as well as at Reviews.io.

What do you get with the company?

Let’s have a look at the list of services the company offers in order to make your cooperation with them as comfortable as possible. 

  • Free revisions . If you have any comments concerning the final draft, you can ask your professional to revise it for free as many times as needed unless it meets your requirements to the fullest.
  • 24/7 assistance . No matter when you realize that you have a programming assignment that should be done in a few days. With ProgrammingDoer, you can place your order 24/7 and get a professional helper as soon as there is an available one.
  • Chat with the experts . When you place your order with the company, you get an opportunity to communicate with your coding helper directly to solve all the problems ASAP.

Extra benefits

If you are not sure if the company can handle your assignment the right way, if they have already worked on similar tasks, or if they have an expert in the needed field, you can check this information on your own. First, you can browse the latest orders and see if there is something close to the issue you have. Then, you can have a look at experts’ profiles and see if there is anyone capable of solving similar issues.

Can I hire someone to do my Java homework?

If you are not sure about your Java programming skills, you can always ask a professional coder to help you out. All you need is to find the service that meets your expectations and place your ‘do my Java assignment’ order with them.  

What is the typical turnaround time for completing a Java homework assignment?

It depends on the service that offers such assistance as well as on your requirements. Some companies can deliver your project in a few hours, but some may need more time. But, you should mind that fast delivery is more likely to cost you some extra money. 

What is the average pricing structure for Java assignment help?

The cost of the help with Java homework basically depends on the following factors: the deadline you set, the complexity level of the assignment, the expert you choose, and the requirements you provide.

How will we communicate and collaborate on my Java homework?

Nowadays, Java assignment help companies provide several ways of communication. In most cases, you can contact your expert via live chat on a company’s website, via email, or a messenger. To see the options, just visit the chosen company’s website and see what they offer.

Regarding the Author:

Nayeli Ellen, a dynamic editor at AcademicHelp, combines her zeal for writing with keen analytical skills. In her comprehensive review titled " Programming Assignment Help: 41 Coding Homework Help Websites ," Nayeli offers an in-depth analysis of numerous online coding homework assistance platforms.

Java programming is not a field that could be comprehended that easily; thus, it is no surprise that young learners are

IMAGES

  1. Explain Variables in Java and Different Types of Variables

    variables assignment in java

  2. Types of Variables in Java with Examples

    variables assignment in java

  3. Variables and types of variables in java with examples

    variables assignment in java

  4. Variables in Java

    variables assignment in java

  5. Variables and Data Types in Java With Example

    variables assignment in java

  6. Java

    variables assignment in java

VIDEO

  1. #20. Assignment Operators in Java

  2. JAVA BASICS

  3. Assignment Operator ( = ) in Java

  4. Mastering Java Variables: A Complete Guide

  5. Instance Variables

  6. Java Beginner 4

COMMENTS

  1. Java Variables

    Variables in Java. Java variable is a name given to a memory location. It is the basic unit of storage in a program. The value stored in a variable can be changed during program execution. Variables in Java are only a name given to a memory location. All the operations done on the variable affect that memory location.

  2. Java Variables

    In Java, there are different types of variables, for example: String - stores text, such as "Hello". String values are surrounded by double quotes. int - stores integers (whole numbers), without decimals, such as 123 or -123. float - stores floating point numbers, with decimals, such as 19.99 or -19.99. char - stores single characters, such as ...

  3. Java: define terms initialization, declaration and assignment

    assignment: throwing away the old value of a variable and replacing it with a new one. initialization: it's a special kind of assignment: the first.Before initialization objects have null value and primitive types have default values such as 0 or false.Can be done in conjunction with declaration. declaration: a declaration states the type of a variable, along with its name.

  4. Assignment, Arithmetic, and Unary Operators (The Java™ Tutorials

    This beginner Java tutorial describes fundamentals of programming in the Java programming language ... You can also combine the arithmetic operators with the simple assignment operator to create compound assignments. For example, x+=1; ... the variable thirdString contains "This is a concatenated string.", ...

  5. Variables (The Java™ Tutorials > Learning the Java Language

    In the Java programming language, the terms "field" and "variable" are both used; this is a common source of confusion among new developers, since both often seem to refer to the same thing. The Java programming language defines the following kinds of variables: Instance Variables (Non-Static Fields) Technically speaking, objects store their ...

  6. 1.4. Expressions and Assignment Statements

    In this lesson, you will learn about assignment statements and expressions that contain math operators and variables. 1.4.1. Assignment Statements ¶. Remember that a variable holds a value that can change or vary. Assignment statements initialize or change the value stored in a variable using the assignment operator =.

  7. Understanding Java Variables: Declaration, Assignment, and Usage

    In this lesson, we will explore the concept of variables in Java. A variable is a container that holds values that are used in a Java program. Every variable is assigned a data type, which tells the compiler what type of data the variable can hold. In this module, we will cover: Variable declaration: We will discuss how to declare variables in ...

  8. All Java Assignment Operators (Explained With Examples)

    Java Assignment Operators are used to assign values to variables. The left operand of the assignment operator is a variable, whereas the right operand is a value or another variable. However, the value or variable given on the assignment operator's right side must be the same data type as the operand on the left side.

  9. Java Variables

    Java Variable Assignment. Assigning a value to a variable in Java follows this pattern: variableName = value ; Here are three concrete examples which assign values to three different variables with different data types myByte = 127; myFloat = 199.99; myString = "This is a text";

  10. Declaring Member Variables (The Java™ Tutorials > Learning the Java

    There are several kinds of variables: Member variables in a class—these are called fields. Variables in a method or block of code—these are called local variables. Variables in method declarations—these are called parameters. The Bicycle class uses the following lines of code to define its fields: public int cadence; public int gear;

  11. Types of Assignment Operators in Java

    To assign a value to a variable, use the basic assignment operator (=). It is the most fundamental assignment operator in Java. It assigns the value on the right side of the operator to the variable on the left side. Example: int x = 10; int x = 10; In the above example, the variable x is assigned the value 10.

  12. 1.7 Java

    An assignment statement designates a value for a variable. An assignment statement can be used as an expression in Java. After a variable is declared, you can assign a value to it by using an assignment statement. In Java, the equal sign = is used as the assignment operator. The syntax for assignment statements is as follows: variable ...

  13. Java Assignment Operators

    Compound Assignment Operators. Sometime we need to modify the same variable value and reassigned it to a same reference variable. Java allows you to combine assignment and addition operators using a shorthand operator. For example, the preceding statement can be written as: i +=8; //This is same as i = i+8;

  14. How to Assign a Value to a Variable in Java • Vertex Academy

    char letter = 'M'; In this line, we declared the variable letter of the char type and, with the help of the "=" symbol, assigned the value "M" to it. Note that since the variable belongs to the char type, we wrote the value of the variable in single quotes. 1. double sum = 145.34567;

  15. Java Operators: Arithmetic, Relational, Logical and more

    2. Java Assignment Operators. Assignment operators are used in Java to assign values to variables. For example, int age; age = 5; Here, = is the assignment operator. It assigns the value on its right to the variable on its left. That is, 5 is assigned to the variable age. Let's see some more assignment operators available in Java.

  16. Day 2

    2. Variable and Assignment. Assignment is denoted by the ' = ' symbol, which means assign value to variables. Variables allow us to store and manipulate data. One important aspect of variables is that their values can be changed.

  17. Java Declare Multiple Variables

    W3Schools offers free online tutorials, references and exercises in all the major languages of the web. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more.

  18. Assigning a variable, what actually happens, Java

    From the JLS section §15.26.2 Compound Assignment Operators: A compound assignment expression of the form E1 op= E2 is equivalent to E1 = (T) ( (E1) op (E2)), where T is the type of E1, except that E1 is evaluated only once. So for your example we have: a = (a) + (a = 2) With the expression evaluated left to right. Hence the output of 3.

  19. Definite Assignment in Java

    Definite Assignment in Java. Every local variable and the final blank field will have an assigned value when any value is accessed. Access to the value will consist of the variable's name or an area that occurs in an expression, except in the left-hand operand of the assignment operator, "=".

  20. 7 Best Java Homework Help Websites: How to Choose Your Perfect Match?

    AssignCode. is one of the best Java assignment help services that you can entrust with programming, mathematics, biology, engineering, physics, and chemistry. A large professional staff makes this ...

  21. Assigning in Java?

    In Java, your variables can be split into two categories: Objects, and everything else (int, long, byte, etc). A primitive type (int, long, etc), holds whatever value you assign it. An object variable, by contrast, holds a reference to an object somewhere. So if you assign one object variable to another, you have copied the reference, both A ...