客户端：
多个客户可以正常收发信息，因为可以同时发送和接受信息，不是发送完信息后等待
返回信息，所以要加入多线程
public class Client {
public static void main(String[]args) throws UnknownHostException, IOException
{
System.out.println("客户端启动中...");
BufferedReader br =new BufferedReader(new InputStreamReader(System.in));
System.out.println("请输入用户名:");
String name=br.readLine();
Socket client =new Socket("localhost",9999);
new Thread(new Send(client,name)).start();//在线程还没启动之前，通过构造方法发送名称,先于信息的发送，
//因为接收信息时，名称已经发送并被读取到变量中
new Thread(new Receive(client)).start();
}
}作为释放资源工具类
public class utils {
public static void close(Closeable... target )
{
for(Closeable it:target)
{
try {
if(null!=it)
{
it.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
} 客户端的发送端封装了：
发送消息
从键盘读取消息
run()
释放资源
public class Send implements Runnable{
private BufferedReader br;
private DataOutputStream dos;
private Socket client;
private boolean flag=true;
private String name;
public Send(Socket client,String name)
{
this.client=client;
this.name=name;
br=new BufferedReader(new InputStreamReader(System.in));
try {
dos=new DataOutputStream(client.getOutputStream());
//发送名称
send(name);
} catch (IOException e) {
this.release();
}
}
public void run()
{
while(flag)
{
String msg=getstr();
send(msg);
}
}
private void release()
{
this.flag=false;
utils.close(dos,client);
}
//从控制台获取消息
private String getstr()
{
try {
String msg=br.readLine();
return msg;
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
private void send(String msg)
{
try {
dos.writeUTF(msg);
dos.flush();
} catch (IOException e) {
release();
}
}
}客户端的接收端封装了:
接收消息
run()
释放资源
public class Receive implements Runnable {
private DataInputStream dis;
private Socket client;
private boolean flag=true;
public Receive(Socket client)
{
this.client=client;
try {
dis=new DataInputStream(client.getInputStream());
} catch (IOException e) {
release();
}
}
private String receive()
{
String msg;
try {
msg = dis.readUTF();
return msg;
} catch (IOException e) {
release();
}
return null;
}
public void run()
{
while(flag)
{
String msg=receive();
System.out.println(msg);
}
}
private void release()
{
this.flag=false;
utils.close(dis,client);
}
}在线聊天室
服务器：
public class Chat {
private static CopyOnWriteArrayList<channel> list=new CopyOnWriteArrayList<>();//使用并发容器，适合多线程
public static void main(String[]args) throws IOException
{
System.out.println("服务器启动中...");
ServerSocket server=new ServerSocket(9999);
while(true)
{
Socket client =server.accept();
System.out.println("一个客户端建立了连接");
channel c=new channel(client);
list.add(c); //容器管理所有成员
new Thread(c).start();
}
}
static class channel implements Runnable{
private DataInputStream dis;
private DataOutputStream dos;
private BufferedReader br;
private Socket client;
private boolean flag;
private String name;
public channel(Socket client)
{
this.client=client;
try {
dis=new DataInputStream(client.getInputStream());
dos=new DataOutputStream(client.getOutputStream());
flag=true;
//获取名称
this.name=receive();
//欢迎到来
this.send("欢迎来到聊天室");
this.sendothers(this.name+"来到了聊天室",true);
} catch (IOException e) {
release(); }
}
//接收消息
private String receive()
{
try {
String msg=dis.readUTF();
return msg;
} catch (IOException e) {
release();
}
return null;
}
//发送给消息
private void send(String msg)
{
try {
dos.writeUTF(msg);
dos.flush();
} catch (IOException e) {
release();
}
}
//群聊:获取自己的消息，发给其他人和私聊功能
private void sendothers(String msg,boolean issys)
{
boolean issecrete =msg.startsWith("@");
if(issecrete)
{
int index=msg.indexOf(":");
String target=msg.substring(1,index);
msg=msg.substring(index+1);
for(channel it:list)
{
if(it.name.equals(target)) //查找目标
{
it.send(this.name+"悄悄地对你说:"+msg); //私聊消息
break;
}
}
}else
{
for(channel it:list)
{
if(it==this)
{
continue;
}
if(!issys)
{
it.send(this.name+":"+msg);
}else
{
it.send(msg);
}
}
}
}
private void release()
{
this.flag=false;
utils.close(dis,dos,client); //写一个工具类,使用Closeable...可变参数
//退出时，从容器里面移掉自身
list.remove(this);
sendothers("离开了聊天室",false);
}
public void run()
{
while(flag)
{
String msg=receive();
sendothers(msg,false);
}
release();
}
}
}