java里监听相关ActionListene的理解。========此代码是错误的，

package com.aa;
import java.awt.Component;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.swing.*;
//事件监听
import javax.swing.*;
class West7 extends JFrame implements ActionListener,KeyListener{//这里的键盘监听也是的，必须实现接口里的方法
	//因为实现ActionListener接口，
	JButton jb1,jb2,jb3;
	JPanel jp;
	JTextField jt;
	JTextArea ta;
	
	public West7(){
		
		ta=new JTextArea(12,30);
		jt=new JTextField(20);
		jt.addActionListener(this);
		jb1=new JButton("OK");
		jb2=new JButton("Exit");
		jp=new JPanel();
		jb1.addActionListener(this);//只要实现了AcitonListener接口，参数this就可以正常了
		jp.add(ta);
		jp.add(jt);
		jp.add(jb1);
		jb2.addKeyListener(this);//键盘监听
		jp.add(jb2);
		this.add(jp);
		this.setVisible(true);
		this.setDefaultCloseOperation(3);
		this.setBounds(100, 200, 500, 300);//就是把对象jb2注册给事件监听者new ActinoListener
		jb2.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){//这是一个匿名的内部类，用来实现对动作事件的处理
				
			}
			
			
			
		} {
			
			@Override
			public void actionPerformed(ActionEvent e) {
				// TODO Auto-generated method stub
				
			}
		})
		
	}
	
	
	
	
	public void send(){
		String s=jt.getText().trim();
	
	}
	public void actionPerformed(ActionEvent e){
		//重写方法
		//好奇怪，竟然没有报错
	
			
			String s=e.getActionCommand();//利用getActionCommand获取按钮名称
			if(s.equals("OK")){
				Component frame;
				JOptionPane.showMessageDialog(frame, "32");
			}else if(s.equals("Exit")){
				
				JOptionPane.showMessageDialog(frame, "哈哈");
			}else {
				
				
				JOptionPane.showMessageDialog(frame, "我呢");
			}
	}
	@Override
	public void keyTyped(KeyEvent e) {
		// TODO Auto-generated method stub
		
	}
	@Override
	public void keyPressed(KeyEvent e) {
	if(e.getKeyCode()==KeyEvent.VK_ENTER){
		send();
		
		//System.out.println("你好");
	}
		
	}
	@Override
	public void keyReleased(KeyEvent e) {
		// TODO Auto-generated method stub
		
	}
	public static void main(String[] args) {
		West7 w=new West7();
		JFrame frame = new JFrame("默默");
		frame.getContentPane().add(comp)
		
	}
}