java.net.SocketException: Connection reset

今天在学习socket编程的时候遇到了一个bug:java.net.SocketException: Connection reset

先来看一下自己的代码：

服务端:

public class ServerSocketDemo {
    public static void main(String[] args) {

        try {
            // 建立一个ServerSocket
            ServerSocket serversocket = new ServerSocket(9999);
            //等待连接
            Socket socket = serversocket.accept();

            //读取数据
            InputStream inputStream = socket.getInputStream();
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);

            String str = bufferedReader.readLine();

            System.out.println(str);

        } catch (IOException e) {
            e.printStackTrace();
        }

    }


}

客户端：

public class ClientSocketDemo {
    public static void main(String[] args) {

        try {
            //建立Socket，指定服务端的ip地址和端口号
            Socket socket = new Socket("127.0.0.1", 9999);

            //往服务端发送数据
            OutputStream outputStream = socket.getOutputStream();
            OutputStreamWriter outputStreamWriter = new OutputStreamWriter(outputStream);
            BufferedWriter bufferedWriter = new BufferedWriter(outputStreamWriter);
            String str = "你好，这是第一个socket程序";
            bufferedWriter.write(str);
            bufferedWriter.flush();

        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}

先运行服务端，再紧接着运行客户端，客户端代码执行完毕后，然后查看服务端控制台，报错：java.net.SocketException: Connection reset。

错误的原因是，客户端代码没有进行关闭操作，加上这段代码就好了。

socket.shutdownOutput();

public class ClientSocketDemo {
    public static void main(String[] args) {

        try {
            //建立Socket，指定服务端的ip地址和端口号
            Socket socket = new Socket("127.0.0.1", 9999);

            //往服务端发送数据
            OutputStream outputStream = socket.getOutputStream();
            OutputStreamWriter outputStreamWriter = new OutputStreamWriter(outputStream);
            BufferedWriter bufferedWriter = new BufferedWriter(outputStreamWriter);
            String str = "你好，这是第一个socket程序";
            bufferedWriter.write(str);
            bufferedWriter.flush();
            // 挂断电话，断开连接
            // 一定要加上这段代码才行。关闭socket连接。
            socket.shutdownOutput();

        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}