saveasimagemenuitem.java

openmap java写的开源数字地图程序. 用applet实现,可以像google map 那样放大缩小地图.

// **********************************************************************
// 
// <copyright>
// 
//  BBN Technologies
//  10 Moulton Street
//  Cambridge, MA 02138
//  [phone]
// 
//  Copyright (C) BBNT Solutions LLC. All rights reserved.
// 
// </copyright>
// **********************************************************************
// 
// $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/gui/menu/SaveAsImageMenuItem.java,v $
// $RCSfile: SaveAsImageMenuItem.java,v $
// $Revision: 1.4.2.1 $
// $Date: 2004/10/14 18:26:56 $
// $Author: dietrick $
// 
// **********************************************************************

package com.bbn.openmap.gui.menu;

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

import com.bbn.openmap.*;
import com.bbn.openmap.util.Debug;
import com.bbn.openmap.image.*;

/**
 * A MenuItem that is capable of looking at MapBean and saving it as
 * an Image
 */
public class SaveAsImageMenuItem extends MapHandlerMenuItem implements
        ActionListener {

    AbstractImageFormatter formatter = null;

    /**
     * @param display A String that will be displayed when this
     *        menuitem is shown in GUI
     * @param in_formatter A formatter that knows how to generate an
     *        image from MapBean.
     */
    public SaveAsImageMenuItem(String display,
            AbstractImageFormatter in_formatter) {
        super(display);
        formatter = in_formatter;
        addActionListener(this);
    }

    public void actionPerformed(ActionEvent ae) {
        Debug.message("saveimage", "SaveAsImageMenuItem: actionPerformed");

        if (mapHandler == null) {
            Debug.output("SaveAsImageMenuItem: mapHandler = null, returning");
            return;
        }

        MapBean mb = (MapBean) mapHandler.get("com.bbn.openmap.MapBean");

        if (mb != null) {
            Debug.message("saveimage", "MapBean found, creating image");
            try {

                while (true) {
                    SaveAsImageFileChooser chooser = new SaveAsImageFileChooser(mb.getWidth(), mb.getHeight());

                    int returnVal = chooser.showSaveDialog(getParent());
                    if (returnVal == JFileChooser.APPROVE_OPTION) {
                        String filename = chooser.getSelectedFile()
                                .getAbsolutePath();
                        if (formatter == null) {
                            break;
                        }

                        filename = checkFileName(filename,
                                formatter.getFormatLabel().toLowerCase());
                        if (filename == null) {
                            // This is the reason for the while
                            // loop, the name didn't really pass
                            // muster, so we'll try again.
                            continue;
                        }

                        int imageHeight = chooser.getImageHeight();
                        int imageWidth = chooser.getImageWidth();

                        byte[] imageBytes = formatter.getImageFromMapBean(mb,
                                imageWidth,
                                imageHeight);
                        FileOutputStream binFile = new FileOutputStream(filename);
                        binFile.write(imageBytes);
                        binFile.close();
                        if (Debug.debugging("saveimage")) {
                            com.bbn.openmap.proj.Projection proj = mb.getProjection();
                            Debug.output("Created image at " + filename
                                    + "where projection covers "
                                    + proj.getUpperLeft() + " to "
                                    + proj.getLowerRight());
                        }
                        break;
                    } else if (returnVal == JFileChooser.CANCEL_OPTION) {
                        break;
                    }
                }
            } catch (IOException e) {
                Debug.error("SaveAsImageMenuItem: " + e);
            }
        }
        return;
    }

    /**
     * A little method that checks the file path to see if it exists,
     * and modifies it with the imageSuffix if it doesn't have one
     * specified by the user. Asks the user if it's OK to overwrite if
     * the file exists.
     * 
     * @param filePath absolute file path to check.
     * @param imageSuffix suffix to append to filePath if it doesn't
     *        already have one. This word should not contain a
     *        starting '.'.
     * @return null if name is no good, a String to use if good.
     */
    protected String checkFileName(String filePath, String imageSuffix) {

        String fileName = filePath.substring(filePath.lastIndexOf(File.separator));
        String newFilePath;

        if (fileName.indexOf('.') == -1) {
            newFilePath = filePath + "." + imageSuffix;
        } else {
            // else leave it alone, user specified suffix
            newFilePath = filePath;
        }

        File file = new File(newFilePath);
        if (file.exists()) {
            // Check to see if it is alright to overwrite.
            int choice = JOptionPane.showConfirmDialog(null,
                    "The file " + newFilePath + " exists, replace?",
                    "Confirm File Replacement",
                    JOptionPane.YES_NO_OPTION);
            if (choice != JOptionPane.YES_OPTION) {
                newFilePath = null;
            }
        }

        return newFilePath;
    }

}