Java正在读取TCP流

Question

我想创建一个Java服务器套接字应用程序，它接收TCP数据包并读取它的内容。根据数据包的内容，它将执行多个操作。我设法达到了读取一些内容并打印字符串System.out.println（sb.toString（））; 但是（a）并非所有内容都被打印出来，（b）我不确定如何按照网络顺序处理内容。一个例子是接收HTTP数据包并从标题中报告“Content-Length”或“User-Agent”。任何一个例子将不胜感激。

public static void main(String[ ] args){

PrintWriter out = null;
BufferedReader in = null;
int bufferSize = 0;


try{
    String message = args[0];
    int count = 0;

    ServerSocket connectionSocket = null;
    try {
        connectionSocket = new ServerSocket(4444);
        System.out.println("Server started");
    } catch (IOException e) {
        System.err.println("Could not listen on port: 4444.");
        System.exit(1);
    }

    Socket clientSocket = null;
    try {
        while(true){
            count++;
            clientSocket = connectionSocket.accept();
            System.out.println("TCP packet received… " +  count);
            InputStream is = clientSocket.getInputStream();

            out = new PrintWriter(clientSocket.getOutputStream());
            in = new BufferedReader(new InputStreamReader(is));

            StringBuilder sb = new StringBuilder();
            String line = null;


            while ((line = in.readLine()) != null) {
                sb.append(line + "\n");
            }
            System.out.println(sb.toString());


            clientSocket.close();
        }           
    } catch (IOException e) {
        System.err.println("Accept failed.");
        System.exit(1);
    }
}
catch(Exception e){
    e.printStackTrace();
}
}