Java reflection

 /*
  My understanding on this is that JAVA REFELECTION is a container or an operator for a Class.
*/

 //package reference
 import java.lang.reflect.*;

 //List the method(s) of a class.
 ...
  
  Class c = Class.forName("ClassName");//load the class' structure
  Method m[] = c.getDeclaredMethods();
  for(int i = 0;i < m.length; i++){
    System.out.println(m[i].getName());
  }
  
 ...
 
 //List the parameters TYPE of a method
 ...
 Class pretype[] = m.getParameterTypes();
 
 //Invoke a specified method
 ...
 Class c = Class.forName("ClassName");
 Class params[] = new Class[2];//2 is the operands' count.
 Method m = c.getMethod("appropriateMethodName",params);
   //if there is no argument in the method, need throw an exception.
 ClassName cn = new ClassName();
 Object args[] = new Object[2];//same with the previous CLASS.
 m.invoke(cn,args);
  //if there's a return value,should use a Object to receive it.like 
  // Object o = m.invoke(cn,args);
  // then convert the type.like
  // Integer i = (Integer)o;

for details:
http://java.sun.com/developer/technicalArticles/ALT/Reflection/