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Assignment Operators

Assignment Operators

Let's take a look at the assignment operator and a few related shorthands.

We'll cover the following...

Introduction

We have already seen the assignment operator, which is used to assign a value to a variable or update its value. The “equal to” sign(=) is used for this operator. Anything on the right of = is assigned to the variable on its left.

Therefore, you always need to place a variable on the left side of =, whereas on the right side can be a value or another variable. Another thing you need to be careful about is the type. You can assign a double value or another double type variable only to a double type variable.

Let’s look at some use cases of the assignment operator.

Java
class AssignmentOperator 
{
    public static void main(String args[]) 
    {
        // assignment operator used to assign a value of zero to the newly declared variable
        int var1 = 0;
        System.out.println(var1); // prints the value of var1, i.e., 0
        int var2; // another int type variable declared
        // assignment operator used to assign a value to a previously declared variable
        var2 = 7; 
        System.out.println(var2); // prints value of var2, i.e., 7
      
        // assignment operator used to update the value of var1 to the value of var2
        var1 = var2;
        System.out.println(var1); // prints updated value of var1 i.e. 7
        System.out.println(var2); // value of var2 remains 7
    }
}

Notice that we create an int variable at line 6 and assign it with 00. Next, we declare another int variable: var2 (at line 9). At line 12, we give var2 a value of 77. Look at line 16.The statement, var1 = var2, changes the value of var1. After this statement, var1 equals 77.

You can also use the assignment operator along with arithmetic operators to update the values of variables. For example, if you want to add 88 to the variable, var1 ...