ProxyClientThread.java

import java.net.Socket;
import java.io.InputStream;
import java.io.DataInputStream;
import java.io.OutputStream;
import java.io.DataOutputStream;
import java.util.ArrayList;
import java.io.IOException;
import java.net.URL;
import java.util.StringTokenizer;

public class ProxyClientThread extends Thread{
    private Socket socket;
    private Socket socketServer;
    private InputStream fromBrowser;
    private DataInputStream fromHost;
    private OutputStream toBrowser;
    private DataOutputStream toHost;
    private String get;
    private String host;
    private ArrayList pedido;
    private int porta;
    HTTPRequest request;

    ClientToServerThread clientToServer;
    Cache cache;
    private DataInputStream fromCache;
    private DataOutputStream toCache;
    byte line[];
    URL url;

    /*
     * Recebe os dados da class proxythread para poder depois tratar os mesmos.
     */
    public ProxyClientThread(Socket socket, Cache cache) {
        this.socket = socket;
        this.cache = cache;
        porta = socket.getPort();
        try {
            fromBrowser = socket.getInputStream();
            toBrowser = socket.getOutputStream();
            start();
        }
        catch (IOException e) {
            System.out.println("Erro: " + e);
        }
    }

    /*
     * Faz o tratamento do pedido
     * Vê se exite na cache e caso existe devolve para o browser, nesse caso o cliente
     * Caso não existe vai buscar as informações ao host, mete as na cache e depois devolve as mesma para o browser, , nesse caso o cliente.
     */
    private void readRequete() throws Exception {
        request = HTTPRequest.readLine(fromBrowser);
        //request = HTTPRequest.parseHTTPRequestAs1_0(fromBrowser);

        String requestedObject = request.requestedObject();
        String post = request.requestPost();
        String contentype = request.requestContentType();
        String contentlength = request.requestContentLength();
        String type = request.requestType();
        // identifica o metodo
        if(type.equals("GET")) 
        { // reply to a GET request
            //System.out.println("browser sent a GET operation");
            if(cache.IsCachable(requestedObject))
            {
                if(cache.IsCached(requestedObject))
                {
                    fromCache = new DataInputStream(cache.getFileInputStream(requestedObject));
                    sendToBrowser(fromCache);
                }else{
                    discoverHost(requestedObject);
                    String lineString = fromHost.readLine();
                    StringTokenizer s = new StringTokenizer(lineString);
                    //aqui retCode fica com a versão do http/1.0                                       
                    String retCode = s.nextToken();
                    //aqui retCode fica com o codigo (ex: 204 ou 200 ou ....)
                    retCode = s.nextToken();
                    if (!retCode.equals("200") || !retCode.equals("302")
                    || !retCode.equals("304"))
                    {
                        toCache = new DataOutputStream(cache.getFileOutputStream(requestedObject));

                        String tempStr = new String(lineString+"\r\n");
                        toHost.writeBytes(tempStr);

                        line = new byte[tempStr.length()];
                        tempStr.getBytes(0,tempStr.length(),line,0);

                        toCache.write(line);

                        if (lineString.length() > 0)
                        {
                            while (true)
                            {
                                lineString = fromHost.readLine();
                                tempStr = new String(lineString+"\r\n");

                                toHost.writeBytes(tempStr);
                                line = new byte[tempStr.length()];
                                tempStr.getBytes(0,tempStr.length(),line,0);

                                //toCache.write(line);

                                if (lineString.length() <= 0) 
                                    break;
                            }
                        }
                        toHost.flush();
                        byte data[] = new byte[4096];
                        int count;
                        while (( count  = fromHost.read(data)) != -1)
                        {
                            line  = new byte[count];
                            System.arraycopy(data,0,line,0,count);
                            toCache.write(line);
                            toBrowser.write(data, 0, count);

                        }
                        toBrowser.flush();
                        toCache.close();
                        cache.AddToTable(requestedObject);
                    }
                }
            }else{
                discoverHost(requestedObject);
                sendToBrowser(fromHost);
            }
        }else if(type.equals("PUT"))
        { // PUT request
            System.out.println("browser sent a PUT operation");

            pedido.add("PUT " + requestedObject + " " + "HTTP/1.0");

        }
        else if(type.equals("POST"))
        { // POST request
            //System.out.println("browser sent a POST operation");
            discoverHost(requestedObject);
            pedido = new ArrayList();
            pedido.add("POST" + requestedObject + " " + "HTTP/1.0");
            pedido.add(contentype);
            pedido.add(contentlength);
            pedido.add(post);

            //             for(int i=0;i<pedido.size();i++)
            //             {
            //                 System.out.println(pedido.get(i));
            //             }

            new ClientToServerThread(toHost, pedido);
            sendToBrowser(fromHost);
        }
    }

    /*
     * Vai permitir saber qual a porta e com qual host vamos enviar e receber os dados
     */
    private void discoverHost(String requestedObject)
    {
        try
        {
            url = new URL("http://"+request.urlHost);

            int portaServer = url.getPort() > 0 ? url.getPort() : 80;

            socketServer = new Socket(url.getHost(),portaServer);

            fromHost = new DataInputStream(socketServer.getInputStream());
            toHost = new DataOutputStream(socketServer.getOutputStream());

            pedido.add("GET " + requestedObject + " " + "HTTP/1.0");
            new ClientToServerThread(toHost, pedido);
        }catch (Exception e) 
        {
            //System.out.println("Erro : "+e);
        }
    }

    /*
     * Recebe dados e envia para o browser
     */
    private void sendToBrowser(DataInputStream from)
    {
        try
        {
            byte data[] = new byte[4096];
            int count;
            while ((count = from.read(data)) != -1)
            {
                toBrowser.write(data,0,count);
            }
        }
        catch (IOException e) 
        {
            //System.out.println("Erro 1 Thread Proxy : " + porta);
        }
        finally
        {
            try
            {
                toBrowser.flush();
                fromCache.close();
            }
            catch (Exception e) {
                //System.out.println("Erro 2 Thread Proxy : " + porta);
            }
        }
    }

    /*
     * Lança o metodoa reaRequete e ao fim fecha todas as linhas de dados.
     */
    public void run() {
        try
        {
            pedido = new ArrayList();
            readRequete();     
        }
        catch (Exception e) 
        {
            //System.out.println("Erro 3 Thread Proxy : " + porta);
        }
        finally
        {
            try 
            {
                if (fromBrowser != null)
                    fromBrowser.close();
                if (toBrowser != null)
                    toBrowser.close();
                if (socket != null)
                    socket.close();
                if (socketServer != null)
                    socketServer.close();
                if (socket != null)
                    socket.close();
                if (socketServer != null)
                    socketServer.close();
            }
            catch (Exception e) {
                //System.out.println("Erro 4 Thread Proxy : " + porta);
            }
        }
    }
}