paginationexample.java

java tutorial.sun公司官方出品。java入门书籍。最新版

/*
 * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Sun Microsystems nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */ 


import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.awt.print.*;

public class PaginationExample implements Printable, ActionListener {

    int[] pageBreaks;  // array of page break line positions.

    /* Synthesise some sample lines of text */
    String[] textLines;
    private void initTextLines() {
        if (textLines == null) {
            int numLines=200;
            textLines = new String[numLines];
            for (int i=0;i<numLines;i++) {
                textLines[i]= "This is line number " + i;
            }
        }
    }

    public int print(Graphics g, PageFormat pf, int pageIndex)
             throws PrinterException {

        Font font = new Font("Serif", Font.PLAIN, 10);
        FontMetrics metrics = g.getFontMetrics(font);
        int lineHeight = metrics.getHeight();

        if (pageBreaks == null) {
            initTextLines();
            int linesPerPage = (int)(pf.getImageableHeight()/lineHeight);
            int numBreaks = (textLines.length-1)/linesPerPage;
            pageBreaks = new int[numBreaks];
            for (int b=0; b<numBreaks; b++) {
                pageBreaks[b] = (b+1)*linesPerPage; 
            }
        }

        if (pageIndex > pageBreaks.length) {
            return NO_SUCH_PAGE;
        }

        /* User (0,0) is typically outside the imageable area, so we must
         * translate by the X and Y values in the PageFormat to avoid clipping
         * Since we are drawing text we
         */
        Graphics2D g2d = (Graphics2D)g;
        g2d.translate(pf.getImageableX(), pf.getImageableY());

        /* Draw each line that is on this page.
         * Increment 'y' position by lineHeight for each line.
         */
        int y = 0; 
        int start = (pageIndex == 0) ? 0 : pageBreaks[pageIndex-1];
        int end   = (pageIndex == pageBreaks.length)
                         ? textLines.length : pageBreaks[pageIndex];
        for (int line=start; line<end; line++) {
            y += lineHeight;
            g.drawString(textLines[line], 0, y);
        }

        /* tell the caller that this page is part of the printed document */
        return PAGE_EXISTS;
    }

    public void actionPerformed(ActionEvent e) {
         PrinterJob job = PrinterJob.getPrinterJob();
         job.setPrintable(this);
         boolean ok = job.printDialog();
         if (ok) {
             try {
                  job.print();
             } catch (PrinterException ex) {
              /* The job did not successfully complete */
             }
         }
    }

    public static void main(String args[]) {

        try {
            String cn = UIManager.getSystemLookAndFeelClassName();
            UIManager.setLookAndFeel(cn); // Use the native L&F
        } catch (Exception cnf) {
        }
        JFrame f = new JFrame("Printing Pagination Example");
        f.addWindowListener(new WindowAdapter() {
           public void windowClosing(WindowEvent e) {System.exit(0);}
        });
        JButton printButton = new JButton("Print Pages");
        printButton.addActionListener(new PaginationExample());
        f.add("Center", printButton);
        f.pack();
        f.setVisible(true);
    }
}