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[QUOTE="Shawn, post: 1938449"]
Hi,

I have a very simple GUI program: it has a menu and a text 
area(JTextArea). In the meu, it has several meu items: "save memo 1", 
"save memo 2", "get memo 1", "get memo 2", "clear", "exit". What the 
program does is: when the user types something and click "save memo 1", 
that line will be saved into an internal string memo1; when the user 
types something else and click "save memo 2", that line will be saved 
into another internal string memo2; when the user clicks "get memo 1", 
that line will be shown in the text area, etc. It is very simple.

public class MemoGUI extends JFrame implements ActionListener
{

....
     public void actionPerformed(ActionEvent e)
     {
         String actionCommand = e.getActionCommand();
         if (actionCommand.equals("Save Memo 1"))
             memo1 = theText.getText();
         else if (actionCommand.equals("Save Memo 2"))
             memo2 = theText.getText();
         else if (actionCommand.equals("Clear"))
             theText.setText("");
         else if (actionCommand.equals("Get Memo 1"))
             theText.setText(memo1);
         else if (actionCommand.equals("Get Memo 2"))
             theText.setText(memo2);
         else if (actionCommand.equals("Exit"))
             System.exit(0);
         else
             theText.setText("Error in memo interface");
     }
} // end of class

I want to do something fancy here: using reflection. Unfortunately I 
know very little about it and I cannot make it work:
(I have used setActionCommand to save1, save2, get1, get2,etc)

public void actionPerformed(ActionEvent e)
     {
         String actionCommand = e.getActionCommand();

/*****Seeking help for the following lines. I am very new to reflection */
         Class c = MenuAction.class;
         Class[] parameterTypes = new Class[] {MenuAction.class};
         Method theMethod;

try {
           theMethod = c.getMethod(actionCommand, null);  //not very sure ?
           theMethod.invoke(obj, args)  //compiler says error here !!!
         } catch (NoSuchMethodException err) {
             System.out.println(err);
         } catch (IllegalAccessException err) {
             System.out.println(err);
         } catch (InvocationTargetException err) {
             System.out.println(err);
         }
     }

private class MenuAction
     {
         void save1()
         {
             memo1 = theText.getText();
         }
         void save2()
         {
             memo2 = theText.getText();
         }
         void get1()
         {
             theText.setText(memo1);
         }
         void get2()
         {
             theText.setText(memo2);
         }
         void clear()
         {
             theText.setText("");
         }
         void exit()
         {
             System.exit(0);
         }
     }

Thank you very much for your help.
[/QUOTE]

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