corejava/corejava第8版/v2ch11/ScriptTest/ScriptTest.java

import java.awt.*;
import java.beans.*;
import java.io.*;
import java.lang.reflect.*;
import java.util.*;
import javax.script.*;
import javax.swing.*;

/**
 * @version 1.00 2007-10-28
 * @author Cay Horstmann
 */
public class ScriptTest
{
   public static void main(final String[] args)
   {
      EventQueue.invokeLater(new Runnable()
         {
            public void run()
            {
               String language;
               if (args.length == 0) language = "js";
               else language = args[0];

               ScriptEngineManager manager = new ScriptEngineManager();
               System.out.println("Available factories: ");
               for (ScriptEngineFactory factory : manager.getEngineFactories())
                  System.out.println(factory.getEngineName());
               final ScriptEngine engine = manager.getEngineByName(language);
               
               if (engine == null)
               {
                  System.err.println("No engine for " + language);
                  System.exit(1);
               }

               ButtonFrame frame = new ButtonFrame();

               try
               {
                  File initFile = new File("init." + language);
                  if (initFile.exists())
                  {
                     engine.eval(new FileReader(initFile));
                  }

                  getComponentBindings(frame, engine);

                  final Properties events = new Properties();
                  events.load(new FileReader(language + ".properties"));
                  for (final Object e : events.keySet())
                  {
                     String[] s = ((String) e).split("\\.");
                     addListener(s[0], s[1], (String) events.get(e), engine);
                  }
               }
               catch (Exception e)
               {
                  e.printStackTrace();
               }

               frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
               frame.setTitle("ScriptTest");
               frame.setVisible(true);
            }
         });
   }

   /**
    * Gathers all named components in a container.
    * @param c the component
    * @param namedComponents
    */
   private static void getComponentBindings(Component c, ScriptEngine engine)
   {
      String name = c.getName();
      if (name != null) engine.put(name, c);
      if (c instanceof Container)
      {
         for (Component child : ((Container) c).getComponents())
            getComponentBindings(child, engine);
      }
   }

   /**
    * Adds a listener to an object whose listener method executes a script.
    * @param beanName the name of the bean to which the listener should be added
    * @param eventName the name of the listener type, such as "action" or "change"
    * @param scriptCode the script code to be executed
    * @param engine the engine that executes the code
    * @param bindings the bindings for the execution
    */
   private static void addListener(String beanName, String eventName, final String scriptCode,
         final ScriptEngine engine) throws IllegalArgumentException, IntrospectionException,
         IllegalAccessException, InvocationTargetException
   {
      Object bean = engine.get(beanName);
      EventSetDescriptor descriptor = getEventSetDescriptor(bean, eventName);
      if (descriptor == null) return;
      descriptor.getAddListenerMethod().invoke(
            bean,
            Proxy.newProxyInstance(null, new Class[] { descriptor.getListenerType() },
                  new InvocationHandler()
                     {
                        public Object invoke(Object proxy, Method method, Object[] args)
                              throws Throwable
                        {
                           engine.eval(scriptCode);
                           return null;
                        }
                     }));

   }

   private static EventSetDescriptor getEventSetDescriptor(Object bean, String eventName)
         throws IntrospectionException
   {
      for (EventSetDescriptor descriptor : Introspector.getBeanInfo(bean.getClass())
            .getEventSetDescriptors())
         if (descriptor.getName().equals(eventName)) return descriptor;
      return null;
   }
}

class ButtonFrame extends JFrame
{
   public ButtonFrame()
   {
      setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);

      panel = new JPanel();
      panel.setName("panel");
      add(panel);

      yellowButton = new JButton("Yellow");
      yellowButton.setName("yellowButton");
      blueButton = new JButton("Blue");
      blueButton.setName("blueButton");
      redButton = new JButton("Red");
      redButton.setName("redButton");

      panel.add(yellowButton);
      panel.add(blueButton);
      panel.add(redButton);
   }

   public static final int DEFAULT_WIDTH = 300;
   public static final int DEFAULT_HEIGHT = 200;

   private JPanel panel;
   private JButton yellowButton;
   private JButton blueButton;
   private JButton redButton;
}