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Java

Posted by Matthew Francis
Matthew Francis
6,967 Points

A variable that stores a method

Recently, I've discovered you can store a method in a variable, however when i tried to do it, It gave me an illegal start of expression, any ideas why?

    public class HelloWorld{
        public static void main(String []args){
            System.out.println("Hello World");
            Bob nBob = new Bob();
            nBob.method();
         }
    }

    class Bob{
        void methodTwo(){
            System.out.println("Check");
        }

        void method(){
            void check =  methodTwo(); //Something is wrong here
        }
    }

1 Answer

tobiaskrause
tobiaskrause
9,160 Points

"The Void class is an uninstantiable placeholder class to hold a reference to the Class object representing the Java keyword void." https://docs.oracle.com/javase/8/docs/api/java/lang/Void.html

void is used for methods like "public void test(){}"...void just means "this method does not return a vlue"

ALSO: You dont "store a method in a variable"...you just store the return value of that method in a variable. For example

int test = somecalculation();

This just means, that the compiler will run somecalculation() when you declare and assign the varaible test. It just jumps to that method. And test justs gets the return value of the method somecalculation().