Java Return Values
Getting results from methods
📤 What are Return Values?
Return values allow methods to send data back to the caller. Instead of just performing actions, methods can calculate results and return them for use elsewhere.
// Method that returns a value
public static int addNumbers(int a, int b) {
return a + b;
}
Usage: int result = addNumbers(5, 3);
result = 8
Key Return Value Concepts
Return Type
Specify what type of data to return
public static int getValue() {}Return Statement
Use return keyword to send data back
return 42;Storing Results
Capture returned values in variables
int result = getValue();Void Methods
Methods that don't return anything
public static void print() {}🔹 Basic Return Examples
Methods that return different types of values:
public class ReturnExample {
// Returns an integer
public static int getAge() {
return 25;
}
// Returns a string
public static String getName() {
return "Alice";
}
// Returns a boolean
public static boolean isStudent() {
return true;
}
public static void main(String[] args) {
int age = getAge();
String name = getName();
boolean student = isStudent();
System.out.println("Name: " + name);
System.out.println("Age: " + age);
System.out.println("Is Student: " + student);
}
}Output:
Name: Alice
Age: 25
Is Student: true
🔹 Calculation Methods
Methods that perform calculations and return results:
public class Calculator {
// Add two numbers
public static int add(int a, int b) {
return a + b;
}
// Multiply two numbers
public static int multiply(int x, int y) {
return x * y;
}
// Calculate area of rectangle
public static double calculateArea(double length, double width) {
return length * width;
}
public static void main(String[] args) {
int sum = add(10, 5);
int product = multiply(4, 7);
double area = calculateArea(5.5, 3.2);
System.out.println("Sum: " + sum);
System.out.println("Product: " + product);
System.out.println("Area: " + area);
}
}Output:
Sum: 15
Product: 28
Area: 17.6
🔹 Using Return Values
Different ways to use returned values:
public class ReturnUsage {
public static int square(int number) {
return number * number;
}
public static String createGreeting(String name) {
return "Hello, " + name + "!";
}
public static void main(String[] args) {
// Store in variable
int result = square(5);
System.out.println("Square of 5: " + result);
// Use directly in print
System.out.println("Square of 3: " + square(3));
// Use in calculations
int total = square(4) + square(6);
System.out.println("4² + 6² = " + total);
// Store string result
String greeting = createGreeting("Bob");
System.out.println(greeting);
}
}Output:
Square of 5: 25
Square of 3: 9
4² + 6² = 52
Hello, Bob!