how to use java.reflection with parameter(s)

[newbiejava]

how to use java.reflection with parameter(s)

public class MyClass1{
    Class1 cls1 = new Class1();
    
    public void myMethod(String s) {
        cls1.msgBox(null, s, Class1.MESSAGE_INFO);
    }
}

//=============

String fcn = "learn38.MyClass1";
Class c1 = Class.forName(fcn);
Method meth1 = c1.getMethod("myMethod", "hello world");
Object theObject1 = c1.newInstance();
meth1.invoke(theObject1);

[Tolls]

Maybe by, I don't know, reading the API for Method.invoke()?

[newbiejava]

Just want to share..

String fcn = "learn38.MyClass1";
Class c1 = Class.forName(fcn);
Object theObject1 = c1.newInstance();
Method meth1 = c1.getDeclaredMethod("myMethod", new Class[]{String.class});

String argu = "This is String to pass";
meth1.invoke(theObject1, new Object[]{argu});

[Tolls]

Don't actually need the array (unless you are using an earlier version of Java of course).
Just list the parameters.

[newbiejava]

hi.. thanks .. but could you please more detail?

[Tolls]

This is the method:
invoke(Object obj, Object... args)

The "..." means you can pass in a list of arguments, eg:

method.invoke(object, param1, param2, param3);

or, in your case:

meth1.invoke(theObject1, argu);

[newbiejava]

so you meant:


Default
Just want to share..

String fcn = "learn38.MyClass1";
Class c1 = Class.forName(fcn);
Object theObject1 = c1.newInstance();
Method meth1 = c1.getDeclaredMethod("myMethod", String.class, String.class);

String argu1 = "This is String 1 to pass";
String argu2 = "This is String 2 to pass";
meth1.invoke(theObject1, argu1, argu2);

[Tolls]

Yes.
And that getDeclaredMethod Strings should be String.class (as you had in the original one), but the compiler would catch that for you.

I suspect (though I haven't looked) that the compiler wraps those up in an array in any case, but it means you don't have to clutter up your code with extra "new Object[]{}" fluff.

[newbiejava]

Thanks Tolls..!