/*
* $Id$
*
* Copyright 2007 Bruno Lowagie.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
package com.lowagie.rups.model;
import com.sun.pdfview.PDFFile;
import com.sun.pdfview.PDFPage;
/**
* Loads all the PDFPage objects for SUN's PDF Renderer
* in Background.
*/
public class PageLoader extends BackgroundTask {
/** The PDFFile (SUN's PDF Renderer class) */
protected PDFFile file;
/** The total number of pages. */
protected int numberOfPages;
/** True for pages with page number equal to index + 1 that are being loaded. */
protected boolean[] busy;
/** True for pages with page number equal to index + 1 that have already been loaded. */
protected boolean[] done;
/**
* Creates a new page loader.
* @param file the PDFFile (SUN's PDF Renderer)
*/
public PageLoader(PDFFile file) {
super();
this.file = file;
numberOfPages = file.getNumPages();
busy = new boolean[numberOfPages];
done = new boolean[numberOfPages];
start();
}
/**
* Getter for the number of pages.
* @return the number of pages in the PDF file.
*/
public int getNumberOfPages() {
return numberOfPages;
}
/**
* Loads a page.
* @param pageNumber the number of the page that has to be loaded.
* @return the PDFPage that has been loaded.
*/
public synchronized PDFPage loadPage(int pageNumber) {
pageNumber--;
if (busy[pageNumber]) return null;
busy[pageNumber] = true;
PDFPage page = file.getPage(pageNumber + 1, true);
if (!done[pageNumber]) {
System.out.println("Loading page " + (pageNumber + 1));
}
done[pageNumber] = true;
busy[pageNumber] = false;
return page;
}
/**
* @see com.lowagie.rups.model.BackgroundTask#doTask()
*/
@Override
public void doTask() {
for (int i = 0; i < numberOfPages; i++) {
loadPage(i + 1);
}
}
}