main.java

用java applet實現的檔案上傳功能

/*
 * $Id: Main.java 116 2006-09-14 11:24:14Z sdrycroft $
 */

/*  Copyright (C) 2005 Simon David Rycroft
 
        This program is free software; you can redistribute it and/or
        modify it under the terms of the GNU General Public License
        as published by the Free Software Foundation; either version 2
        of the License, or (at your option) any later version.
 
        This program 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 General Public License for more details.
 
        You should have received a copy of the GNU General Public License
        along with this program; if not, write to the Free Software
        Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA. */

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;

import java.awt.dnd.DropTargetListener;
import java.awt.dnd.DropTargetDropEvent;
import java.awt.dnd.DropTargetDragEvent;
import java.awt.dnd.DropTargetEvent;
import java.awt.dnd.DropTarget;
import java.awt.dnd.DnDConstants;
import java.awt.datatransfer.*;

import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.GridLayout;
import java.io.File;
import java.io.PrintStream;
import java.io.BufferedReader;
import java.net.URL;
import java.net.URI;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.Vector;
import javax.swing.BorderFactory;
import javax.swing.JApplet;
import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.TableColumn;
import javax.swing.UIManager;
import javax.swing.SwingConstants;
import netscape.javascript.JSObject;

import java.net.UnknownHostException;
import java.net.MalformedURLException;
import javax.swing.UnsupportedLookAndFeelException;

public class Main extends JApplet implements MouseListener, DropTargetListener {
    
    JTable table;
    JButton add, remove, upload, help;
    TableData tabledata;
    TableColumn sizeColumn;
    File [] files;
    JLabel progCompletion;
    JProgressBar progBar;
    int sentBytes,totalBytes,buttonClicked;
    Color backgroundColour, columnHeadColourBack, columnHeadColourFore;
    PostletLabels pLabels;
    
    // Boolean set to false when a javascript method is executed
    boolean javascript;
    
    // Parameters
    URL endPageURL, helpPageURL, destinationURL;
    boolean warnMessage, autoUpload;
    String language,endpage,helppage;
    int maxThreads;
    String [] fileExtensions;
    
    // URI list flavor (Hack for linux)
    DataFlavor uriListFlavor;
    
    public void init() {
        // First thing, output the version, for debugging purposes.
        System.out.println("POSTLET VERSION: 0.10");
        String date = "$Date: 2006-09-14 12:24:14 +0100 (Thu, 14 Sep 2006) $";
        System.out.println(date.substring(7,date.length()-1));
        
	// URI list flavor:
	try {
		uriListFlavor = new DataFlavor("text/uri-list;class=java.lang.String");
	}
	catch (ClassNotFoundException cnfe){
		errorMessage(System.out, "No class found for DataFlavor");
	}
	
        // Set the javascript to false, and start listening for clicks
        javascript = false;
        JavascriptListener jsListen = new JavascriptListener(this);
        jsListen.start();
        buttonClicked = 0; // Default of add click.
        
        getParameters();
        pLabels = new PostletLabels(language, getCodeBase());
        layoutGui();
        
    }
    
    private void layoutGui(){
        
        // Set the look of the applet
        try {
            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        } catch (UnsupportedLookAndFeelException exc){;} catch (IllegalAccessException exc){;} catch (ClassNotFoundException exc){;} catch (InstantiationException exc){;}
        
        // Get the main pane to add content to.
        Container pane = getContentPane();
        
        // Attempt to add drop listener to the whole applet
        try {
            DropTarget dt = new DropTarget();
            dt.addDropTargetListener(this);
            pane.setDropTarget(dt);
        } catch (java.util.TooManyListenersException tmle){
            errorMessage(System.out, "Too many listeners to drop!");
        }
        
        // Table for the adding of Filenames and sizes to.
        tabledata = new TableData(pLabels.getLabel(0),pLabels.getLabel(1)+" -KB ");
        table = new JTable(tabledata);
        table.setColumnSelectionAllowed(false);
        //table.setDragEnabled(false); // This method is not available to Java 3!
        sizeColumn = table.getColumn(pLabels.getLabel(1)+" -KB ");
        sizeColumn.setMaxWidth(100);
        table.getColumn(pLabels.getLabel(1)+" -KB ").setMinWidth(100);
        if (columnHeadColourBack != null && backgroundColour != null){
            errorMessage(System.out, "setting the tables colours");
            table.getTableHeader().setBackground(columnHeadColourBack);
            table.getTableHeader().setForeground(columnHeadColourFore);
            table.setBackground(backgroundColour);
        }
        JScrollPane scrollPane = new JScrollPane(table);
        scrollPane.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
        
        // Add the scroll pane/table to the main pane
        pane.add(scrollPane, BorderLayout.CENTER);
        
        JPanel rightPanel = new JPanel(new GridLayout(4,1,10,10));
        rightPanel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
        
        add = new JButton(pLabels.getLabel(6));
        add.addMouseListener(this);
        rightPanel.add(add);
        
        remove = new JButton(pLabels.getLabel(7));
        remove.addMouseListener(this);
        remove.setEnabled(false);
        rightPanel.add(remove);
        
        upload = new JButton(pLabels.getLabel(8));
        upload.addMouseListener(this);
        upload.setEnabled(false);
        rightPanel.add(upload);
        
        help = new JButton(pLabels.getLabel(9));
        help.addMouseListener(this);
        rightPanel.add(help);
        pane.add(rightPanel,"East");
        
        JPanel progPanel = new JPanel(new GridLayout(2, 1));
        progPanel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
        
        progCompletion = new JLabel(pLabels.getLabel(10),SwingConstants.CENTER);
        progPanel.add(progCompletion);
        
        progBar = new JProgressBar();
        progPanel.add(progBar);
        progPanel.setBorder(BorderFactory.createEmptyBorder(5,25,5,25));
        
        if (backgroundColour != null){
            pane.setBackground(backgroundColour);
            rightPanel.setBackground(backgroundColour);
            scrollPane.setBackground(backgroundColour);
            progPanel.setBackground(backgroundColour);
        }
        // Always set the table background colour as White.
        // May change this if required, only would require alot of Params!
        scrollPane.getViewport().setBackground(Color.white);
        
        pane.add(progPanel,"South");
        
        // If the destination has not been set/isn't a proper URL
        // Then deactivate the buttons.
        if (destinationURL == null)
            add.setEnabled(false);
    }
    
    public void errorMessage(PrintStream out, String message){
        out.println("***"+message+"***");
    }
    
    // Helper method for getting the parameters from the webpage.
    private void getParameters(){
        
        /*  LANGUAGE */
        try {
            language = getParameter("language");
            if (language == "" || language == null)
                language = "EN";
        } catch (NullPointerException nullLang){
            // Default language being set
            language = "EN";
            errorMessage(System.out,"language is null");
        }
        
        /*  DESTINATION  */
        try {
            destinationURL = new URL(getParameter("destination"));
	    // Following line is for testing, and to hard code the applet to postlet.com
	    //destinationURL = new URL("http://www.postlet.com/example/javaUpload.php");
        } catch(java.net.MalformedURLException malurlex){
            // Do something here for badly formed destination, which is ESENTIAL.
            errorMessage(System.out, "Badly formed destination:###"+getParameter("destination")+"###");
            JOptionPane.showMessageDialog(null, pLabels.getLabel(3),pLabels.getLabel(5), JOptionPane.ERROR_MESSAGE);
        } catch(java.lang.NullPointerException npe){
            // Do something here for the missing destination, which is ESENTIAL.
            errorMessage(System.out,"destination is null");
            JOptionPane.showMessageDialog(null, pLabels.getLabel(4), pLabels.getLabel(5), JOptionPane.ERROR_MESSAGE);
        }
        
        /*  BACKGROUND  */
        try {
            Integer bgci = new Integer(getParameter("backgroundcolour"));
            backgroundColour = new Color(bgci.intValue());
        } catch(NumberFormatException numfe){
            errorMessage(System.out, "background colour is not a number:###"+getParameter("backgroundcolour")+"###");
        } catch (NullPointerException nullred){
            errorMessage(System.out, "background colour is null");
        }
        
        /*  TABLEHEADERFOREGROUND  */
        try {
            Integer thfi = new Integer(getParameter("tableheadercolour"));
            columnHeadColourFore = new Color(thfi.intValue());
        } catch(NumberFormatException numfe){
            errorMessage(System.out, "table header colour is not a number:###"+getParameter("tableheadcolour")+"###");
        } catch (NullPointerException nullred){
            errorMessage(System.out, "table header colour is null");
        }
        
        /*  TABLEHEADERBACKGROUND  */
        try {
            Integer thbi = new Integer(getParameter("tableheaderbackgroundcolour"));
            columnHeadColourBack = new Color(thbi.intValue());
        } catch(NumberFormatException numfe){
            errorMessage(System.out, "table header back colour is not a number:###"+getParameter("tableheaderbackgroundcolour")+"###");
        } catch (NullPointerException nullred){
            errorMessage(System.out, "table header back colour is null");
        }
        
        /*  FILEEXTENSIONS  */
        try {
            fileExtensions = getParameter("fileextensions").split(",");
        } catch(NullPointerException nullfileexts){
            errorMessage(System.out, "file extensions is null");
        }
        
        /*  WARNINGMESSAGE  */
        try {
            if (getParameter("warnmessage").toLowerCase() == "true")
                warnMessage = true;
            else
                warnMessage = false;
        } catch(NullPointerException nullwarnmessage){
            errorMessage(System.out, "warnmessage is null");
            warnMessage = false;
        }
        
        /*  AUTOUPLOAD  */
        try {
            if (getParameter("autoupload").toLowerCase() == "true")
                autoUpload = true;
            else
                autoUpload = false;
        } catch(NullPointerException nullwarnmessage){
            errorMessage(System.out, "autoUpload is null");
            autoUpload = false;
        }
        
        /*  MAXTHREADS  */
        try {
            Integer maxts = new Integer(getParameter("maxthreads"));
            maxThreads = maxts.intValue();
        } catch (NullPointerException nullmaxthreads){
            errorMessage(System.out, "maxthreads is null");
        } catch (NumberFormatException nummaxthreads){
            errorMessage(System.out, "maxthread is not a number");}
        
        /*  ENDPAGE  */
        try {
            endPageURL = new URL(getParameter("endpage"));
        } catch(java.net.MalformedURLException malurlex){
            errorMessage(System.out, "endpage is badly formed:###"+getParameter("endpage")+"###");
        } catch(java.lang.NullPointerException npe){
            errorMessage(System.out, "endpage is null");
        }
        
        /*  HELPPAGE  */
        try {
            helpPageURL = new URL(getParameter("helppage"));
        } catch(java.net.MalformedURLException malurlex){