java NIO实现简单聊天程序

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。