本文实例为大家分享了java NIO实现简单聊天程序的具体代码，供大家参考，具体内容如下
服务端
功能：
1、接受客户端连接
2、发送消息
3、读取客户端消息
Server.java
public class Server {
private Selector selector;
private ByteBuffer writeBuffer = ByteBuffer.allocate(1024);
private ByteBuffer readBuffer = ByteBuffer.allocate(1024);
Msg msg = new Msg();
MsgSender msgSender = new MsgSender(msg);
public static void main(String[] args) {
Server server = new Server();
new Thread(server.msgSender).start();
server.start();
}
//初始化服务端
public Server() {
try {
this.selector = Selector.open();
ServerSocketChannel ssc = ServerSocketChannel.open();
ssc.configureBlocking(false);
ssc.bind(new InetSocketAddress(8899));
ssc.register(this.selector, SelectionKey.OP_ACCEPT);
System.out.println("服务端初始化完毕。。。。");
} catch (IOException e) {
e.printStackTrace();
}
}
//启动服务端等待selector事件
public void start() {
while (true) {
try {
int num = this.selector.select();
if (num > 0) {
Iterator<SelectionKey> it = this.selector.selectedKeys().iterator();
while (it.hasNext()) {
SelectionKey key = it.next();
it.remove();
if (key.isValid()) {
if (key.isAcceptable()) {
this.accept(key);
}
if (key.isReadable()) {
this.read(key);
}
if (key.isWritable()) {
this.write(key);
}
}
}
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
//发送消息
private void write(SelectionKey key) {
SocketChannel sc = (SocketChannel) key.channel();
try {
sc.configureBlocking(false);
} catch (IOException e) {
e.printStackTrace();
}
//判断是否有消息需要发送
if(msg!=null && msg.getFlag()){
System.out.println(msg);
try {
msg.setFlag(false);
writeBuffer.clear();
writeBuffer.put(msg.getContent().getBytes());
writeBuffer.flip();
sc.write(writeBuffer);
} catch (IOException e) {
e.printStackTrace();
}
}
}
//读取客户端消息
private void read(SelectionKey key) {
SocketChannel sc = (SocketChannel) key.channel();
try {
sc.configureBlocking(false);
readBuffer.clear();
int read = sc.read(readBuffer);
if (read == -1) {
sc.close();
key.cancel();
}
readBuffer.flip();
System.out.println(new String(readBuffer.array()));
} catch (IOException e) {
e.printStackTrace();
}
}
//接受客户端连接
private void accept(SelectionKey key) {
ServerSocketChannel ssc = (ServerSocketChannel) key.channel();
try {
SocketChannel sc = ssc.accept();
System.out.println(String.format("a new client join!!!host:%s;port:%d", sc.socket().getLocalAddress(), sc.socket().getPort()));
sc.configureBlocking(false);
sc.register(this.selector, SelectionKey.OP_READ | SelectionKey.OP_WRITE);
} catch (IOException e) {
e.printStackTrace();
}
}
}Msg.java
class Msg {
private Boolean flag=false;
private String content;
public Boolean getFlag() {
return flag;
}
public void setFlag(Boolean flag) {
this.flag = flag;
}
public String getContent() {
return content;
}
public void setContent(String content) {
this.content = content;
}
@Override
public String toString() {
return "Msg{" +
"flag=" + flag +
", content='" + content + '\'' +
'}';
}
}MsgSender.java
class MsgSender implements Runnable{
private Msg msg;
public MsgSender(Msg msg) {
this.msg = msg;
}
@Override
public void run() {
while (true) {
System.out.println("input:\n");
Scanner scanner = new Scanner(System.in);
this.msg.setContent(scanner.next());
this.msg.setFlag(true);
}
}
}客户端
采用的时BIO，简单的使用线程实现消息的读写
功能：
1、连接服务端
2、读取消息
3、发送消息
public class Client {
private SocketChannel sc;
ByteBuffer writeBuffer = ByteBuffer.allocate(1024);
ByteBuffer readBuffer = ByteBuffer.allocate(1024);
public static void main(String[] args) {
new Client();
}
public Client() {
try {
sc = SocketChannel.open();
//连接服务端
sc.connect(new InetSocketAddress(8899));
//发送消息
this.write(sc);
//读取消息
this.read(sc);
} catch (IOException e) {
e.printStackTrace();
}
}
private void read(SocketChannel sc) {
new Thread(new Runnable() {
@Override
public void run() {
while (true) {
try {
readBuffer.clear();
int read = sc.read(readBuffer);
readBuffer.flip();
System.out.println(new String(readBuffer.array()));
} catch (IOException e) {
e.printStackTrace();
}
}
}
}).start();
}
private void write(SocketChannel sc) {
new Thread(new Runnable() {
@Override
public void run() {
while (true) {
Scanner scanner = new Scanner(System.in);
String next = scanner.next();
writeBuffer.clear();
writeBuffer.put(next.getBytes());
writeBuffer.flip();
try {
sc.write(writeBuffer);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}).start();
}
}以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程网。
