使用线程从InputStream读取数据

Question

I tried to use read() method from InputStream class but it blocks the thread, and i tried readLine() method that blocks the thread too.

After this attempts I used this:

    public static void main(String[] args) throws IOException{
        Socket s = new Socket();
        String host = "";
        s.connect(new InetSocketAddress(host, 23));

        Response response = new Response(s);

        response .start();

        if(response .isInterrupted()){
            System.out.println(response .getSb().toString());
        }


    }

public class Response extends Thread {
    Socket s;
    BufferedReader s_in = null;
    InputStream in = null;
    private StringBuffer sb = new StringBuffer();

    public Response(Socket s){
        this.s = s;
    }

    @Override
    public void run() {
        try {
            s_in = new BufferedReader(new InputStreamReader(s.getInputStream()));
            in = s.getInputStream();

            char ch;
            int i;


            while(!Thread.currentThread().isInterrupted()){
                i = s_in.read();
                ch = (char) i;
                System.out.print(ch);
                getSb().append(getSb());
            }

            System.out.print(getSb());

        } catch (IOException ex) {
            Logger.getLogger(Response.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    public StringBuffer getSb() {
        return sb;
    }
}

public class Message extends Thread{
    Socket s;
    PrintWriter s_out = null;

    public Message(Socket s){
        this.s = s;
    }

    @Override
    public void run(){
        try {
            s_out = new PrintWriter(s.getOutputStream(), true);
        } catch (IOException ex) {
            Logger.getLogger(Message.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

But when I run the application the socket does not have enough time to send all the data to InputStream.

So, I might verify when the stream ends. To start reading.

Thanks for helping !

Answer 1

I don't know why you aren't using a buffered stream, or putting this reader in it's own thread, since it should always be reading (or ready to read) from the socket, which means blocking.

But, with the code you've provided, the easiest way to improve your situation is to read until there's no more bytes to read, which is not what you're actually doing. More bytes could have come in while you're executing the for loop. Try this instead:

int i;
char c;
while (in.available() > 0)
{
    i = s_in.read();
    System.out.print(ch = (char)i);
    sb.append(ch);
}

It really doesn't solve your problem, because you're not buffering your input with a separate thread, and you can still exit the loop before you receive all the data you expected to get.