source: trunk/gsdl3/src/java/org/greenstone/gsdl3/gs3build/util/HTMLLoader.java@ 6897

package org.greenstone.gsdl3.gs3build.util;



import java.net.*;

import java.io.*;



public class HTMLLoader implements Runnable

{ URL                   from;

    StringBuffer    HTML;

    boolean             loaded;

    boolean             error;

    boolean             notFound;

    Thread              thread;

    static int      running;



    /**

     * Constructor to load given URL

     */

    public HTMLLoader(URL from)

    { this.from     = from;

        this.HTML   = new StringBuffer();

        this.loaded = false;

        this.error  = false;

        this.thread = null;
    }



    /**

     * @return <code>0</code> if finished running; any other value if

     *         still executing

     */

    public static synchronized int running()

    { return running;

    }



    /**

     * Starts the thread; the method <code>load</code> is a synonym for this

     */

    public synchronized void start()

    { if (thread == null)

        { thread = new Thread(this);

            thread.start();

            running ++;

        }

//      System.out.println("Running: "+running);

    }



    /**

     * Do the actual loading; this will multi-thread with calling task

     */

    public void run()

    {   URLConnection connect;

        int                     length, i, c;

        byte                    inbuffer[];

        InputStream     in;



        inbuffer = new byte[128];



        this.notFound   = false;
//      System.out.println("Running loader");



        // get connection and test length

        try

        {   connect = this.from.openConnection();

        }

        catch (IOException ioex)

        { this.loaded   = true;

            this.error  =   true;

            running --;
            System.out.println(ioex);

            return;

        }


        length = connect.getContentLength();

        if (length == 0)

        { this.loaded = true;

            running --;
            System.out.println("Empty");

            return;

        }



        // get an inputstream to the document body

        try

        { in = connect.getInputStream();

        }

        catch (IOException ioex)

        { this.error    = true;

            this.loaded = true;

            running --;
            System.out.println("Open failed" + ioex);

            return;

        }



        if (length < 0)

        {   if (connect.getHeaderField(0) != null &&

                    connect.getHeaderField(0).indexOf("404") >= 0)

            {   this.notFound   = true;

                this.error      = true;

                this.loaded     = true;

                running --;
                System.out.println("Not found");

                return;

            }

        }

//      System.out.println("Ready to read " + length);



        // read in the document body

        i = 0;

        c = 0;

        while (true || i < length)

        { // read in 128 characters (abort on IO Exception)

            try

            { c = in.read(inbuffer);

            }

            catch (IOException ioex)

            { break;

            }

            // System.out.println("read " + c);



            // if no characters were read, end, otherwise add it to the body

            if (c != -1)

            { if (c > 0)

                { this.HTML.append(new String(inbuffer, 0, c));

                    i += c;

                }

            }

            else

            { break;

            }

            // if an incomplete buffer was read (ie no characters remain), end

/*          if (c < inbuffer.length && i >= length)

            { break;

            }*/

        }



        // Close file

        try

        {   in.close();

        }

        catch (IOException ioex)

        {   //System.out.println("Closed except "+ioex);

        }

    
        this.loaded = true;

    running --;

    }



    /**

     * Do the actual loading (calls a Start on the Thread)

     */

    public void load()

    {   this.start();

//      this.run();

    }



    /**

     * @return HTML text as a <code>String</code>.

     */

    public synchronized String HTML()

    { if (this.error)

        { return "Error";

        }

        return this.HTML.toString();

    }



    /**

     * @return  <code>true</code> if the file has successfully loaded

     */

    public boolean loaded()

    { return this.loaded;

    }



    protected void finalize() throws Throwable

    {   this.thread = null;

        this.from       = null;

        this.HTML       = null;

        super.finalize();

    }



    static

    { running = 0;

    }

}