/*
**************************************************************************
* Copyright (C) 2005-2007, International Business Machines Corporation *
* and others. All Rights Reserved. *
**************************************************************************
*
*/
package com.ibm.icu.dev.demo.charsetdet;
import java.awt.event.*;
import java.awt.*;
import java.io.*;
import java.net.URL;
import java.nio.ByteBuffer;
import java.nio.charset.Charset;
import java.security.AccessControlException;
import javax.swing.*;
import com.ibm.icu.charset.CharsetICU;
import com.ibm.icu.dev.demo.impl.DemoApplet;
import com.ibm.icu.text.CharsetDetector;
import com.ibm.icu.text.CharsetMatch;
/**
* This simple application demonstrates how to use the CharsetDetector API. It
* opens a file or web page, detects the encoding, and then displays it using that
* encoding.
*/
public class DetectingViewer extends JFrame implements ActionListener
{
/**
* For serialization
*/
private static final long serialVersionUID = -2307065724464747775L;
private JTextPane text;
private JFileChooser fileChooser;
/**
* @throws java.awt.HeadlessException
*/
public DetectingViewer()
{
super();
DemoApplet.demoFrameOpened();
try {
fileChooser = new JFileChooser();
} catch (AccessControlException ace) {
System.err.println("no file chooser - access control exception. Continuing without file browsing. "+ace.toString());
fileChooser = null; //
}
// setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(800, 800);
setJMenuBar(makeMenus());
text = new JTextPane();
text.setContentType("text/plain");
text.setText("");
text.setSize(800, 800);
Font font = new Font("Arial Unicode MS", Font.PLAIN, 24);
text.setFont(font);
JScrollPane scrollPane = new JScrollPane(text);
getContentPane().add(scrollPane);
setVisible(true);
addWindowListener(
new WindowAdapter() {
public void windowClosing(WindowEvent e) {
// setVisible(false);
// dispose();
doQuit();
}
} );
}
public void actionPerformed(ActionEvent event)
{
String cmd = event.getActionCommand();
if (cmd.equals("New...")) {
doNew();
} else if (cmd.equals("Open File...")) {
doOpenFile();
} else if (cmd.equals("Open URL...")) {
doOpenURL();
} else if (cmd.equals("Quit")) {
doQuit();
}
}
public static void main(String[] args)
{
new DetectingViewer();
}
private void errorDialog(String title, String msg)
{
JOptionPane.showMessageDialog(this, msg, title, JOptionPane.ERROR_MESSAGE);
}
private BufferedInputStream openFile(File file)
{
FileInputStream fileStream = null;
try {
fileStream = new FileInputStream(file);
} catch (Exception e) {
errorDialog("Error Opening File", e.getMessage());
return null;
}
return new BufferedInputStream(fileStream);
}
// private void openFile(String directory, String filename)
// {
// openFile(new File(directory, filename));
// }
private BufferedInputStream openURL(String url)
{
InputStream s = null;
try {
URL aURL = new URL(url);
s = aURL.openStream();
} catch (Exception e) {
errorDialog("Error Opening URL", e.getMessage());
return null;
}
return new BufferedInputStream(s);
}
private String encodingName(CharsetMatch match)
{
return match.getName() + " (" + match.getLanguage() + ")";
}
private void setMatchMenu(CharsetMatch[] matches)
{
JMenu menu = getJMenuBar().getMenu(1);
JMenuItem menuItem;
menu.removeAll();
for (int i = 0; i < matches.length; i += 1) {
CharsetMatch match = matches[i];
menuItem = new JMenuItem(encodingName(match) + " " + match.getConfidence());
menu.add(menuItem);
}
}
private byte[] scriptTag = {(byte) 's', (byte) 'c', (byte) 'r', (byte) 'i', (byte) 'p', (byte) 't'};
private byte[] styleTag = {(byte) 's', (byte) 't', (byte) 'y', (byte) 'l', (byte) 'e'};
private static int BUFFER_SIZE = 100000;
private boolean openTag(byte[] buffer, int offset, int length, byte[] tag)
{
int tagLen = tag.length;
int bufRem = length - offset;
int b;
for (b = 0; b < tagLen && b < bufRem; b += 1) {
if (buffer[b + offset] != tag[b]) {
return false;
}
}
return b == tagLen;
}
private boolean closedTag(byte[] buffer, int offset, int length, byte[] tag)
{
if (buffer[offset] != (byte) '/') {
return false;
}
return openTag(buffer, offset + 1, length, tag);
}
private byte[] filter(InputStream in)
{
byte[] buffer = new byte[BUFFER_SIZE];
int bytesRemaining = BUFFER_SIZE;
int bufLen = 0;
in.mark(BUFFER_SIZE);
try {
while (bytesRemaining > 0) {
int bytesRead = in.read(buffer, bufLen, bytesRemaining);
if (bytesRead <= 0) {
break;
}
bufLen += bytesRead;
bytesRemaining -= bytesRead;
}
} catch (Exception e) {
// TODO: error handling?
return null;
}
boolean inTag = false;
boolean skip = false;
int out = 0;
for (int i = 0; i < bufLen; i += 1) {
byte b = buffer[i];
if (b == (byte) '<') {
inTag = true;
if (openTag(buffer, i + 1, bufLen, scriptTag) ||
openTag(buffer, i + 1, bufLen, styleTag)) {
skip = true;
} else if (closedTag(buffer, i + 1, bufLen, scriptTag) ||
closedTag(buffer, i + 1, bufLen, styleTag)) {
skip = false;
}
} else if (b == (byte) '>') {
inTag = false;
} else if (! (inTag || skip)) {
buffer[out++] = b;
}
}
byte[] filtered = new byte[out];
System.arraycopy(buffer, 0, filtered, 0, out);
return filtered;
}
private CharsetMatch[] detect(byte[] bytes)
{
CharsetDetector det = new CharsetDetector();
det.setText(bytes);
return det.detectAll();
}
private CharsetMatch[] detect(BufferedInputStream inputStream)
{
CharsetDetector det = new CharsetDetector();
try {
det.setText(inputStream);
return det.detectAll();
} catch (Exception e) {
// TODO: error message?
return null;
}
}
private void show(InputStream inputStream, CharsetMatch[] matches, String title)
{
InputStreamReader isr;
char[] buffer = new char[1024];
int bytesRead = 0;
if (matches == null || matches.length == 0) {
errorDialog("Match Error", "No matches!");
return;
}
try {
StringBuffer sb = new StringBuffer();
String encoding = matches[0].getName();
inputStream.reset();
if (encoding.startsWith("UTF-32")) {
byte[] bytes = new byte[1024];
int offset = 0;
int chBytes = 0;
Charset utf32 = CharsetICU.forNameICU(encoding);
while ((bytesRead = inputStream.read(bytes, offset, 1024)) >= 0) {
offset = bytesRead % 4;
chBytes = bytesRead - offset;
sb.append(utf32.decode(ByteBuffer.wrap(bytes)).toString());
if (offset != 0) {
for (int i = 0; i < offset; i += 1) {
bytes[i] = bytes[chBytes + i];
}
}
}
} else {
isr = new InputStreamReader(inputStream, encoding);
while ((bytesRead = isr.read(buffer, 0, 1024)) >= 0) {
sb.append(buffer, 0, bytesRead);
}
isr.close();
}
this.setTitle(title + " - " + encodingName(matches[0]));
setMatchMenu(matches);
text.setText(sb.toString());
} catch (IOException e) {
errorDialog("IO Error", e.getMessage());
} catch (Exception e) {
errorDialog("Internal Error", e.getMessage());
}
}
private void doNew()
{
// open a new window...
}
private void doOpenFile()
{
int retVal = fileChooser.showOpenDialog(this);
if (retVal == JFileChooser.APPROVE_OPTION) {
File file = fileChooser.getSelectedFile();
BufferedInputStream inputStream = openFile(file);
if (inputStream != null) {
CharsetMatch[] matches = detect(inputStream);
show(inputStream, matches, file.getName());
}
}
}
private void doOpenURL()
{
String url = (String) JOptionPane.showInputDialog(this, "URL to open:", "Open URL", JOptionPane.PLAIN_MESSAGE,
null, null, null);
if (url != null && url.length() > 0) {
BufferedInputStream inputStream = openURL(url);
if (inputStream != null) {
byte[] filtered = filter(inputStream);
CharsetMatch[] matches = detect(filtered);
show(inputStream, matches, url);
}
}
}
private void doQuit()
{
DemoApplet.demoFrameClosed();
this.setVisible(false);
this.dispose();
}
private JMenuBar makeMenus()
{
JMenu menu = new JMenu("File");
JMenuItem mi;
mi = new JMenuItem("Open File...");
mi.setAccelerator((KeyStroke.getKeyStroke(KeyEvent.VK_O, ActionEvent.CTRL_MASK)));
mi.addActionListener(this);
menu.add(mi);
if(fileChooser == null) {
mi.setEnabled(false); // no file chooser.
}
mi = new JMenuItem("Open URL...");
mi.setAccelerator((KeyStroke.getKeyStroke(KeyEvent.VK_U, ActionEvent.CTRL_MASK)));
mi.addActionListener(this);
menu.add(mi);
mi = new JMenuItem("Quit");
mi.setAccelerator((KeyStroke.getKeyStroke(KeyEvent.VK_Q, ActionEvent.CTRL_MASK)));
mi.addActionListener(this);
menu.add(mi);
JMenuBar mbar = new JMenuBar();
mbar.add(menu);
menu = new JMenu("Detected Encodings");
mbar.add(menu);
return mbar;
}
}