In Java, the return
statement is used to exit a method and optionally return a value to the caller. Here are some examples of how the return
statement works in Java:
You can use the return
statement to return a value from a method. The return type of the method should match the type of value you’re returning. Here’s an example:
public int add(int a, int b) {
int sum = a + b;
return sum; // Returns the sum of a and b
}
In this example, the add
method takes two integers as input, calculates their sum, and returns the result as an int
.
You can use the return
statement to exit a method early, before reaching the end of the method. For example, you might have a method that checks a condition and returns immediately if the condition is met:
public boolean isPositive(int number) {
if (number > 0) {
return true; // Return early if the number is positive
} else {
return false;
}
}
In this example, the isPositive
method returns true
if the input number is positive, and it returns false
for non-positive numbers.
Void methods (methods with a return type of void
) don’t return a value, but you can use return
to exit the method early. In this case, you don’t provide a value after return
, as there’s nothing to return. Here’s an example:
public void printMessage(String message) {
if (message == null) {
System.out.println("Message is null.");
return; // Exit the method early
}
System.out.println(message);
}
In this example, if the message
is null
, the method prints a message and then exits early using return
.
You can use return
to exit a loop (e.g., for
or while
) early if a certain condition is met. Here’s an example:
public int findFirstPositive(int[] numbers) {
for (int num : numbers) {
if (num > 0) {
return num; // Exit the method and return the first positive number found
}
}
return -1; // Return -1 if no positive numbers are found
}
In this example, the method searches for the first positive number in an array and returns it. If no positive number is found, it returns -1
.
The return
statement is a fundamental feature in Java for controlling the flow of your program and providing results from methods to the calling code.