public interface MessageHandler
{
  void perform(HandlerContext ctx) throws Exception;
}

.....
  Object o = class.newInstance();
  if (o instanceof MessageHanlder)
  {
     ((MessageHandler)o).perform(...);
  }
....

// ---------------------------- HandlerContext.java --------------------- 
package ru.sql.forum.db2;

import java.util.HashMap;
import java.util.Map;

public class HandlerContext {
    private Map map = new HashMap();

     /**
     * @param key to set
     * @param value to set
     */ 
    public void setValue(String key, String value) {
        map.put(key, value);
    }

     /**
     * @param key to retrieve
     * @return value from the context
     */ 
    public Object getValue(String key) {
        return map.get(key);
    }

}

// ---------------------------- MessageHandler.java --------------------- 
package ru.sql.forum.db2;

public interface MessageHandler {
    void perform(HandlerContext ctx) throws Exception;
}

//  ---------------------------- Dispatcher.java ------------------------ 
package ru.sql.forum.db2;

import java.util.PropertyResourceBundle;
import java.util.ResourceBundle;

public class Dispatcher
{
    public static void main(String[] args) {
        try {
            if (args.length <  1 )
                throw new Exception("TXID not defined as parameter");
            ResourceBundle bundle = PropertyResourceBundle
                .getBundle("ru.sql.forum.db2.dispatcher");
            Class clazz = Class.forName(bundle.getString(args[ 0 ]));
            Object o = clazz.newInstance();
            if (o instanceof MessageHandler) {
                HandlerContext ctx = new HandlerContext();
                ctx.setValue("TXID", args[ 0 ]);
                ((MessageHandler) o).perform(ctx);
            }
            else
                throw new Exception(
                    "Class should implement MessageHandler interface");
        }
        catch (Exception e) {
            e.printStackTrace(System.out);
        }
    }
}

// ---------------------------- Handler1.java --------------------------- 
package ru.sql.forum.db2;

public class Handler1
    implements MessageHandler
{
    public void perform(HandlerContext ctx) throws Exception {
        System.out.println("Handler1 called for TX {"
            + ctx.getValue("TXID")
            + "}");
    }
}

// ---------------------------- Handler2.java --------------------------- 
package ru.sql.forum.db2;

public class Handler2
    implements MessageHandler
{
    public void perform(HandlerContext ctx) throws Exception {
        System.out.println("Handler2 called for TX {"
            + ctx.getValue("TXID")
            + "}");
    }
}

# ---------------------------- dispatcher.properties -------------------- 
# Put this file in the same directory where Dispatcher.class file is
 101 =ru.sql.forum.db2.Handler1
 102 =ru.sql.forum.db2.Handler2

 ------------------------------------------------------------------------