InputThread.java

/*
 * Curecoin 2.0.0a Source Code
 * Copyright (c) 2015 Curecoin Developers
 * Distributed under MIT License
 * Requires Apache Commons Library
 * Supports Java 1.7+
 */

import java.io.*;
import java.net.*;
import java.util.*;

/**
 * InputThread only reads data from a peer, and never sends data to prevent blocking and waiting, or some terrible constant back-and-forth keepalive.
 * All data read in is stored in an ArrayList<String>, with each line stored independently.
 * Data is accessed through a passthrough all the way through PeerNetwork. 
 */
public class InputThread extends Thread
{
    private Socket socket;

    //Private instead of public so that object can control calls to receivedData. Acts as a buffer... the same data shouldn't be read more than once.
    private ArrayList<String> receivedData = new ArrayList<String>();

    /**
     * Constructor to set class socket variable
     */
    public InputThread(Socket socket)
    {
        this.socket = socket;
    }

    /**
     * Constantly reads from the input stream of the socket, and saves any received data to the ArrayList<St
     */
    public void run()
    {
        try
        {
            BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            String input;
            while ((input = in.readLine()) != null)
            {
                receivedData.add(input);
                //System.out.println("RUN(): " + input);
                //System.out.println("size: " + receivedData.size());
            }
        } catch (Exception e)
        {
            System.out.println("Peer " + socket.getInetAddress() + " disconnected.");
        }
    }

    /**
     * Doesn't actually 'read data' as that's done asynchronously in the threadded run function.
     * However, readData is an easy way to think about it--as receivedData acts as a buffer, holding received data until the daemon is ready to handle it.
     * Generally, the size of receivedData will be small. However, in some instances (like when downloading many blocks), it can grow quickly.
     * 
     * @return ArrayList<String> Data pulled from receivedData
     */
    @SuppressWarnings("unused")
	public ArrayList<String> readData()
    {
        //System.out.println("readData() called!");
        //System.out.println("We have " + receivedData.size() + " pieces!");
        //Don't want to mess with the ArrayList while run() is modifying it.
        ArrayList<String> inputBuffer = new ArrayList<String>(receivedData);
        if (inputBuffer == null)
        {
            inputBuffer = new ArrayList<String>();
        }
        receivedData = new ArrayList<String>(); //Resets 'buffer'
        return inputBuffer;
    }
}