clientchat.java

1、 聊天室的实现

import java.awt.*;
import java.io.*;
import java.net.*;
import java.applet.*;
import java.util.Hashtable;

import javax.swing.JOptionPane;

public class ClientChat extends Applet implements Runnable
{
	final static int PORT = 1234;

	Socket socket = null;

	DataInputStream in = null;

	DataOutputStream out = null;

	InputNameTextField nameField = null;

	static ChatArea chatArea = null;

	Hashtable listTable;

	Panel north, center;

	Thread chatThread;

	public void init()
	{
		int width = getSize().width;
		int height = getSize().height;

		listTable = new Hashtable();
		setLayout(new BorderLayout());

		nameField = new InputNameTextField(listTable);
		int h = nameField.getSize().height;

		chatArea = new ChatArea("", listTable, width, height - (h + 5));
		chatArea.setVisible(false);

		north = new Panel(new FlowLayout(FlowLayout.LEFT));
		center = new Panel();

		north.add(nameField);
		center.add(chatArea);
		add(north, BorderLayout.NORTH);
		add(center, BorderLayout.CENTER);
		validate();
	}

	public void start()
	{
		if (socket != null && in != null && out != null) // 一般情况下都为null，清理
		{
			try
			{
				socket.close();
				in.close();
				out.close();
			} catch (IOException e)
			{
				// TODO 自动生成 catch 块
				e.printStackTrace();
			}
			chatArea.setVisible(false);

		}
		try
		{
			socket = new Socket(this.getCodeBase().getHost(), PORT);
			in = new DataInputStream(socket.getInputStream());
			out = new DataOutputStream(socket.getOutputStream());
		} catch (IOException ee)
		{
			// ChatArea.remind.setText("无法连接服务器！");
			JOptionPane.showMessageDialog(null, "无法连接服务器！\n请检查是否已连上服务器",
					"连接错误！", JOptionPane.ERROR_MESSAGE);
			stop();
		}
		if (socket != null)
		{
			InetAddress address = socket.getInetAddress();
			// remindLabel.setText("成功连接服务器:" + address);
			nameField.setSocketConnection(socket, in, out);
			north.validate();
		}
		if (chatThread == null)
		{
			chatThread = new Thread(this);
			chatThread.start();
		}
	}

	public void stop()
	{
		try
		{
			socket.close();
			in.close();
			out.close();
			nameField.setVisible(false); // 
			chatArea.setVisible(false); // 
			chatThread = null;
		} catch (IOException e)
		{
			this.showStatus(e.toString());
		}
	}

	public void run()
	{
		while (chatThread != null) // 可以聊天，则显示聊天界面
		{
			if (nameField.getOkToChat() == true)
			{
				chatArea.setVisible(true);
				chatArea.setName(nameField.getName());
				chatArea.setSocketConnection(socket, in, out);
				center.validate();
				break;
			}
			try
			{
				Thread.sleep(200);
			} catch (Exception e)
			{
			}
		}
	}
}