TextCutPaste.java Source code

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Here is the source code for TextCutPaste.java

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/*
 * 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.
 */

/**
 * TextCutPaste.java requires the following file:
 *     TextTransferHandler.java
 */

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.StringSelection;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.event.KeyEvent;

import javax.swing.BorderFactory;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.TransferHandler;
import javax.swing.UIManager;
import javax.swing.text.BadLocationException;
import javax.swing.text.DefaultEditorKit;
import javax.swing.text.Document;
import javax.swing.text.JTextComponent;
import javax.swing.text.Position;

/**
 * Example code that shows a text component that supports both cut, copy and
 * paste (using the DefaultEditorKit's built-in actions) and drag and drop.
 */
public class TextCutPaste extends JPanel {
    TextTransferHandler th;

    public TextCutPaste() {
        super(new BorderLayout());

        setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));

        // Create the transfer handler.
        TextTransferHandler th = new TextTransferHandler();

        // Create some text fields.
        JPanel buttonPanel = new JPanel(new GridLayout(3, 1));
        JTextField textField = new JTextField("Cut, copy and paste...", 30);
        textField.setTransferHandler(th);
        textField.setDragEnabled(true);
        buttonPanel.add(textField);
        textField = new JTextField("or drag and drop...", 30);
        textField.setTransferHandler(th);
        textField.setDragEnabled(true);
        buttonPanel.add(textField);
        textField = new JTextField("from any of these text fields.", 30);
        textField.setTransferHandler(th);
        textField.setDragEnabled(true);
        buttonPanel.add(textField);
        add(buttonPanel, BorderLayout.CENTER);
    }

    /**
     * Create an Edit menu to support cut/copy/paste.
     */
    public JMenuBar createMenuBar() {
        JMenuItem menuItem = null;
        JMenuBar menuBar = new JMenuBar();
        JMenu mainMenu = new JMenu("Edit");
        mainMenu.setMnemonic(KeyEvent.VK_E);

        menuItem = new JMenuItem(new DefaultEditorKit.CutAction());
        menuItem.setText("Cut");
        menuItem.setMnemonic(KeyEvent.VK_T);
        mainMenu.add(menuItem);

        menuItem = new JMenuItem(new DefaultEditorKit.CopyAction());
        menuItem.setText("Copy");
        menuItem.setMnemonic(KeyEvent.VK_C);
        mainMenu.add(menuItem);

        menuItem = new JMenuItem(new DefaultEditorKit.PasteAction());
        menuItem.setText("Paste");
        menuItem.setMnemonic(KeyEvent.VK_P);
        mainMenu.add(menuItem);

        menuBar.add(mainMenu);
        return menuBar;
    }

    /**
     * Create the GUI and show it. For thread safety, this method should be
     * invoked from the event-dispatching thread.
     */
    private static void createAndShowGUI() {
        // Create and set up the window.
        JFrame frame = new JFrame("TextCutPaste");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        // Create and set up the menu bar and content pane.
        TextCutPaste demo = new TextCutPaste();
        frame.setJMenuBar(demo.createMenuBar());
        demo.setOpaque(true); // content panes must be opaque
        frame.setContentPane(demo);

        // Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        // Schedule a job for the event-dispatching thread:
        // creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                // Turn off metal's use of bold fonts
                UIManager.put("swing.boldMetal", Boolean.FALSE);
                createAndShowGUI();
            }
        });
    }
}

/*
 * 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.
 */

/**
 * TextTransferHandler.java is used by the TextCutPaste.java example.
 */

/**
 * An implementation of TransferHandler that adds support for the import and
 * export of text using drag and drop and cut/copy/paste.
 */
class TextTransferHandler extends TransferHandler {
    // Start and end position in the source text.
    // We need this information when performing a MOVE
    // in order to remove the dragged text from the source.
    Position p0 = null, p1 = null;

    /**
     * Perform the actual import. This method supports both drag and drop and
     * cut/copy/paste.
     */
    public boolean importData(TransferHandler.TransferSupport support) {
        // If we can't handle the import, bail now.
        if (!canImport(support)) {
            return false;
        }

        // Fetch the data -- bail if this fails
        String data;
        try {
            data = (String) support.getTransferable().getTransferData(DataFlavor.stringFlavor);
        } catch (UnsupportedFlavorException e) {
            return false;
        } catch (java.io.IOException e) {
            return false;
        }

        JTextField tc = (JTextField) support.getComponent();
        tc.replaceSelection(data);
        return true;
    }

    /**
     * Bundle up the data for export.
     */
    protected Transferable createTransferable(JComponent c) {
        JTextField source = (JTextField) c;
        int start = source.getSelectionStart();
        int end = source.getSelectionEnd();
        Document doc = source.getDocument();
        if (start == end) {
            return null;
        }
        try {
            p0 = doc.createPosition(start);
            p1 = doc.createPosition(end);
        } catch (BadLocationException e) {
            System.out.println("Can't create position - unable to remove text from source.");
        }
        String data = source.getSelectedText();
        return new StringSelection(data);
    }

    /**
     * These text fields handle both copy and move actions.
     */
    public int getSourceActions(JComponent c) {
        return COPY_OR_MOVE;
    }

    /**
     * When the export is complete, remove the old text if the action was a move.
     */
    protected void exportDone(JComponent c, Transferable data, int action) {
        if (action != MOVE) {
            return;
        }

        if ((p0 != null) && (p1 != null) && (p0.getOffset() != p1.getOffset())) {
            try {
                JTextComponent tc = (JTextComponent) c;
                tc.getDocument().remove(p0.getOffset(), p1.getOffset() - p0.getOffset());
            } catch (BadLocationException e) {
                System.out.println("Can't remove text from source.");
            }
        }
    }

    /**
     * We only support importing strings.
     */
    public boolean canImport(TransferHandler.TransferSupport support) {
        // we only import Strings
        if (!support.isDataFlavorSupported(DataFlavor.stringFlavor)) {
            return false;
        }
        return true;
    }
}