Call known function (with parameters) in class whose name is defined by string variable

Tag: java,function,class,variables

I have a bunch of classes of various names and each has a performLogic function that accepts a number of preset parameters (always the same):

public final class DoSomeAction extends SetupAction {
    public void performLogic(param1, param2...

I want a way where I can call it like this:

String actionName = "DoSomeAction";
actionName.performLogic(param1, param2...);

Hope this is clear what I am trying to do.

Thanks for feedback and pointing me towards class.forName() After some further research I was able to implement the following:

try {
    Class actionClass = Class.forName(blockAction);

    Object obj = actionClass.newInstance();

    Class[] parameterTypes = new Class[2];
    parameterTypes[0] = String.class;
    parameterTypes[1] =  String.class;

    Method performLogic = actionClass.getDeclaredMethod("performLogic", parameterTypes);

    performLogic.invoke(obj, param1, param2);
}
catch(ClassNotFoundException e) {
    cat.error("Class not found: " + e.toString());
}

Best How To :

Your can use Reflection

Object action = ???; // perhaps you need .newInstance() for action class
                     // Hopefully you have a interface with performLogic

String methodName = "performLogic";
try {
    Method method = action.getClass().getMethod(methodName, param1.class, param2.class);
    method.invoke(action, param1, param2);
} catch (SecurityException | NoSuchMethodException e) {
    // Error by get Method
} catch (IllegalArgumentException | IllegalAccessException | InvocationTargetException e) {        
    // Error by call Method
}

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