Return type in java is used inside of method for the purpose of returning value in program when method complete it’s execution. A java return type may be int, float, double, or void data type(void returns nothing).
It is reserved keyword in java and determine the ending of method.
Example 1:
public class Main {
static int add(int x) {
return 5 + x;
}
public static void main(String[] args) {
System.out.println(add(3));
}
}
Output:
8
In the above example add() methods return 5+x as output which is 8.
Examples 2:
class A { byte b= 10; public int returnValue() { System.out.println("Hello"); return b; } public static void main(String arg[]) { A ob= new A(); System.out.println(ob.returnValue()); } }
Example to return Integer Value in Java
Example 3:
public class ReturnExample1 { int display() { return 4; } public static void main(String[] args) { ReturnExample1 e1 =new ReturnExample1(); System.out.println(e1.display()); } }
Output:
4
Let see can we use Return in Void method.
public class ReturnExample2 { void display() { return null; } public static void main(String[] args) { ReturnExample2 e =new ReturnExample2(); e.display(); } }
Output:
Void methods cannot return a value
Program for Return value in java
// Java program to illustrate usage // of return keyword class A { // Since return type of RR method is double // so this method should return double value double RR(double a, double b) { double sum = 0; sum = (a + b) / 2.0; // return statement below: return sum; } public static void main(String[] args) { System.out.println(new A().RR(5.5, 6.5)); } }
Output:
6.0
Critical points of Return types in java.
- Return type is used to exit from the method.
- You cannot use return keyword in void method.
- return statement need not to be last statement in a method, but it must be last statement to execute in a method.
- The value passed with return keyword must match with return type of the method.