CODEWITHSUNDEEP
java
user3698201
user3698201

Reputation: 25

Calling a method by a String

I want to call a method by using a string. I get that this is possible; from what I understand reflection is the way to go. However, I'm having a hard time getting it to work and this is what I want.

For instance:

String method ="punch";

int punch(){
    return 1;
}

I want to call the method by the string name. Can someone show me an example?

public class foo {
    String method ="punch";

    int punch() {
        return 1;
    }

    public static void main(String[] args) throws FileNotFoundException, IOException, ClassNotFoundException, NoSuchMethodException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {
        Class<?> myClass = Class.forName("foo");
        Method myMethod = myClass.getMethod("punch");
        Object retObject = myMethod.invoke(null);
    }
}

What do I need to do so that I can get the number 1?

Upvotes: 0

Views: 98

Answers (1)

Thilo
Thilo

Reputation: 262474

Object retObject = myMethod.invoke(null);

That would only work for a static method.

For an instance method, you need to pass in the instance that you want to invoke the method on.

Object retObject = myMethod.invoke(instanceOfFoo);

Also, the method may need to be public (or be made accessible separately).

Upvotes: 5

Related Questions