Define object of a class derived from a string variable - class

Question

Following is the use case:
Invoker class (with main method)
public class Invoker {
public static void main(String[] args) {
String class_file="Batch_Status";
}
}
Class to be invoked (with the same method name as that of class name, e.g. in this case it is Batch_Status)
import java.util.*;
public class Batch_Status {
public static void Batch_Status(String args) {
......
......Code Goes Here
......
}
}
Now the problem is that i am not able to define any object such as test in Invoker class by using the value of string class_file such as class_file test = new class_file();
Above is just a snippet, in my production code the values in the String variable will vary and for each value, a different class file (the name of the class file will be same as that of value of the String variable).
Please suggest.
Regards

Answer 1

This code demonstrates being able to retrieve a class instance given a string:
String classString = "com.rbs.testing.Test";
try {
Class c = Class.forName(classString);
Test test = (Test) c.newInstance();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (InstantiationException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
}
If you don't know what class to cast to yet, you can dump
c.newInstance();
into an Object class, then use if else clauses until you find out the class type contained in the object.
Object o = c.newInstance();
if (o instanceof Test) {
} else if(o instanceof Test2) {
I hope this helps. Sorry if I misunderstood your need.

Answer 2

Thanks Michael,
In fact, while doing some brainstorming, i also did the same thing and it worked as desired. Now i am able to call the method as well which is also derived from the same string variable. Following is the code which i tried:
import java.lang.reflect.*;
import java.util.logging.*;
public class Invoker {
public static void main(String[] args){
try {
String str ="Batch_Status";
Class t = Class.forName(str);
t.getMethods()[0].invoke(t,str);
} catch (ClassNotFoundException | IllegalAccessException | InvocationTargetException ex) {
Logger.getLogger(Invoker.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
And when checked your reply, it seems to be quite similar. Thanks, i really appreciate that.
Regards