Java Check if Function was Called by Another-CodePudding

I've got 2 functions within the same class, say function_1() and function_2() in the following structure;

public class JavaClass {
    function_1() {
        if (wasCalledbyfunction_2()) {
            ... do something
        }
    ...
    }

    function_2() {
        function_1()
        ...
    }

I'm having trouble finding a way to implement the wasCalledbyfunction_2() method. That is, if function_1 was called by function 2, I want to change the behaviour of the former.

I've tried looking into using the in-built Stack Trace methods but I'm lacking some clarity on how to actually implement it.

Any help is appreciated!

CodePudding user response：

You can use : StackTraceElement.getMethodName(), the call of this method returns the name of the method containing the execution point represented by this stack trace element.

public class JavaClass {
    void function_1() {

        StackTraceElement stackTraceElements[] = (new Throwable()).getStackTrace();
        if (stackTraceElements[1].getMethodName().equals("function_2")) {
            System.out.println("Called by function_2");
        } else {
            System.out.println("Called by another method !");
        }
    }

    void function_2() {
        function_1();
    }

    void function_3() {
        function_1();
    }

    public static void main(String[] args) {
        new JavaClass().function_2();
        new JavaClass().function_3();

    }
}

Output :

Called by function_2
Called by another method !

stackTraceElements[0].getMethodName() will contain the current method name : function_1

stackTraceElements[2].getMethodName() will contain the caller method name : function_2

stackTraceElements[3].getMethodName() will contain the first caller method name : main