Understand the idea

Overloaded methods share a name but differ in parameter types, number, or order. The compiler chooses an overload using the call and the declared types. Return type alone is not enough to distinguish overloads.

Explore the details

Method Overloading

With method overloading, multiple methods can have the same name with different parameters:

Consider the following example, which has two methods that add numbers of different type:

Instead of defining two methods that should do the same thing, it is better to overload one.

In the example below, we overload the plusMethod method to work for both int and double:

Overloading Rules

• Methods must have the same name
• They must differ in number of parameters, type of parameters, or both
• Return type alone is not enough to distinguish overloaded methods
• Overloading is resolved at compile time (static dispatch)

// Overloaded area() — same name, different parameters
static double area(double r) {
    return Math.PI * r * r;          // circle
}
static double area(double w, double h) {
    return w * h;                    // rectangle
}
static double area(double b, double h, boolean triangle) {
    return 0.5 * b * h;             // triangle
}

// Java picks the right version automatically
System.out.println(area(5.0));           // 78.54 (circle)
System.out.println(area(4.0, 6.0));      // 24.0  (rectangle)

When to Use Method Overloading

• When the same logical operation should work on different data types (e.g., add(int) vs add(double))
• When varying numbers of arguments make sense for the same action (e.g., draw(radius) vs draw(width, height))
• To provide convenience versions of a method with sensible defaults
• Avoid overloading when the methods do fundamentally different things — use distinct names instead

A complete runnable example

This complete Main.java program focuses on the lesson idea. Reference fragments above may demonstrate individual statements; this example includes the imports, entry point, and supporting types it needs.

public class Main {
    public static void main(String[] args) throws Exception {
        System.out.println(Area.of(4));
        System.out.println(Area.of(4, 3));
    }
}
class Area {
    static int of(int side) { return side * side; }
    static int of(int width, int height) { return width * height; }
}

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Change it. Run it. Understand it.

Load this lesson example into the editor. Change one value or statement, predict the result, then press RUN to execute Java.

Make it your own

Your learning checkpoint

• Explain the example without reading the output first.
• Make the change requested in the practice task.
• Describe why the result changed—or why compilation failed.

Ready to move on? Follow the next lesson in course order, or return to the curriculum to review a prerequisite.