Does Java Allow Default Parameter Values in Functions?

Can Java functions use default parameter values like C++?

void MyParameterizedFunction(String param1, int param2, boolean param3=false);

Java does not support default parameter values as found in languages like C++. Instead, Java employs method overloading to achieve similar functionality. This allows developers to create multiple versions of a method, each with different parameter signatures.

public class Example {
    // Main method with mandatory parameters
    public void myFunction(String param1, int param2) {
        myFunction(param1, param2, false); // Calls the overloaded method with a default value for param3
    }

    // Overloaded method with a boolean parameter
    public void myFunction(String param1, int param2, boolean param3) {
        // Handle the parameters here
    }
}

Causes

• Java's design emphasizes simplicity and clarity over complexity.
• Enforcement of strict parameter counts aids in maintaining method signatures and API stability.

Solutions

• Utilize method overloading to simulate default parameters: define multiple method signatures with and without certain parameters.
• Use wrapper classes or options to pass optional parameters, creating constructors or factory methods that can handle defaults.

Mistake: Assuming default values can be set directly in parameter lists in Java.

Solution: Remember that Java does not support this; use method overloading instead.

Mistake: Overloading too many similar methods, making the codebase difficult to manage.

Solution: Keep the number of overloads reasonable and clearly documented.