| /* |
| * Copyright (c) 1996, 2006, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.awt.datatransfer; |
| |
| import java.awt.EventQueue; |
| |
| import java.util.Set; |
| import java.util.HashSet; |
| import java.util.Arrays; |
| |
| import java.io.IOException; |
| |
| import sun.awt.EventListenerAggregate; |
| |
| |
| /** |
| * A class that implements a mechanism to transfer data using |
| * cut/copy/paste operations. |
| * <p> |
| * {@link FlavorListener}s may be registered on an instance of the |
| * Clipboard class to be notified about changes to the set of |
| * {@link DataFlavor}s available on this clipboard (see |
| * {@link #addFlavorListener}). |
| * |
| * @see java.awt.Toolkit#getSystemClipboard |
| * @see java.awt.Toolkit#getSystemSelection |
| * |
| * @author Amy Fowler |
| * @author Alexander Gerasimov |
| */ |
| public class Clipboard { |
| |
| String name; |
| |
| protected ClipboardOwner owner; |
| protected Transferable contents; |
| |
| /** |
| * An aggregate of flavor listeners registered on this local clipboard. |
| * |
| * @since 1.5 |
| */ |
| private EventListenerAggregate flavorListeners; |
| |
| /** |
| * A set of <code>DataFlavor</code>s that is available on |
| * this local clipboard. It is used for tracking changes |
| * of <code>DataFlavor</code>s available on this clipboard. |
| * |
| * @since 1.5 |
| */ |
| private Set currentDataFlavors; |
| |
| /** |
| * Creates a clipboard object. |
| * |
| * @see java.awt.Toolkit#getSystemClipboard |
| */ |
| public Clipboard(String name) { |
| this.name = name; |
| } |
| |
| /** |
| * Returns the name of this clipboard object. |
| * |
| * @see java.awt.Toolkit#getSystemClipboard |
| */ |
| public String getName() { |
| return name; |
| } |
| |
| /** |
| * Sets the current contents of the clipboard to the specified |
| * transferable object and registers the specified clipboard owner |
| * as the owner of the new contents. |
| * <p> |
| * If there is an existing owner different from the argument |
| * <code>owner</code>, that owner is notified that it no longer |
| * holds ownership of the clipboard contents via an invocation |
| * of <code>ClipboardOwner.lostOwnership()</code> on that owner. |
| * An implementation of <code>setContents()</code> is free not |
| * to invoke <code>lostOwnership()</code> directly from this method. |
| * For example, <code>lostOwnership()</code> may be invoked later on |
| * a different thread. The same applies to <code>FlavorListener</code>s |
| * registered on this clipboard. |
| * <p> |
| * The method throws <code>IllegalStateException</code> if the clipboard |
| * is currently unavailable. For example, on some platforms, the system |
| * clipboard is unavailable while it is accessed by another application. |
| * |
| * @param contents the transferable object representing the |
| * clipboard content |
| * @param owner the object which owns the clipboard content |
| * @throws IllegalStateException if the clipboard is currently unavailable |
| * @see java.awt.Toolkit#getSystemClipboard |
| */ |
| public synchronized void setContents(Transferable contents, ClipboardOwner owner) { |
| final ClipboardOwner oldOwner = this.owner; |
| final Transferable oldContents = this.contents; |
| |
| this.owner = owner; |
| this.contents = contents; |
| |
| if (oldOwner != null && oldOwner != owner) { |
| EventQueue.invokeLater(new Runnable() { |
| public void run() { |
| oldOwner.lostOwnership(Clipboard.this, oldContents); |
| } |
| }); |
| } |
| fireFlavorsChanged(); |
| } |
| |
| /** |
| * Returns a transferable object representing the current contents |
| * of the clipboard. If the clipboard currently has no contents, |
| * it returns <code>null</code>. The parameter Object requestor is |
| * not currently used. The method throws |
| * <code>IllegalStateException</code> if the clipboard is currently |
| * unavailable. For example, on some platforms, the system clipboard is |
| * unavailable while it is accessed by another application. |
| * |
| * @param requestor the object requesting the clip data (not used) |
| * @return the current transferable object on the clipboard |
| * @throws IllegalStateException if the clipboard is currently unavailable |
| * @see java.awt.Toolkit#getSystemClipboard |
| */ |
| public synchronized Transferable getContents(Object requestor) { |
| return contents; |
| } |
| |
| |
| /** |
| * Returns an array of <code>DataFlavor</code>s in which the current |
| * contents of this clipboard can be provided. If there are no |
| * <code>DataFlavor</code>s available, this method returns a zero-length |
| * array. |
| * |
| * @return an array of <code>DataFlavor</code>s in which the current |
| * contents of this clipboard can be provided |
| * |
| * @throws IllegalStateException if this clipboard is currently unavailable |
| * |
| * @since 1.5 |
| */ |
| public DataFlavor[] getAvailableDataFlavors() { |
| Transferable cntnts = getContents(null); |
| if (cntnts == null) { |
| return new DataFlavor[0]; |
| } |
| return cntnts.getTransferDataFlavors(); |
| } |
| |
| /** |
| * Returns whether or not the current contents of this clipboard can be |
| * provided in the specified <code>DataFlavor</code>. |
| * |
| * @param flavor the requested <code>DataFlavor</code> for the contents |
| * |
| * @return <code>true</code> if the current contents of this clipboard |
| * can be provided in the specified <code>DataFlavor</code>; |
| * <code>false</code> otherwise |
| * |
| * @throws NullPointerException if <code>flavor</code> is <code>null</code> |
| * @throws IllegalStateException if this clipboard is currently unavailable |
| * |
| * @since 1.5 |
| */ |
| public boolean isDataFlavorAvailable(DataFlavor flavor) { |
| if (flavor == null) { |
| throw new NullPointerException("flavor"); |
| } |
| |
| Transferable cntnts = getContents(null); |
| if (cntnts == null) { |
| return false; |
| } |
| return cntnts.isDataFlavorSupported(flavor); |
| } |
| |
| /** |
| * Returns an object representing the current contents of this clipboard |
| * in the specified <code>DataFlavor</code>. |
| * The class of the object returned is defined by the representation |
| * class of <code>flavor</code>. |
| * |
| * @param flavor the requested <code>DataFlavor</code> for the contents |
| * |
| * @return an object representing the current contents of this clipboard |
| * in the specified <code>DataFlavor</code> |
| * |
| * @throws NullPointerException if <code>flavor</code> is <code>null</code> |
| * @throws IllegalStateException if this clipboard is currently unavailable |
| * @throws UnsupportedFlavorException if the requested <code>DataFlavor</code> |
| * is not available |
| * @throws IOException if the data in the requested <code>DataFlavor</code> |
| * can not be retrieved |
| * |
| * @see DataFlavor#getRepresentationClass |
| * |
| * @since 1.5 |
| */ |
| public Object getData(DataFlavor flavor) |
| throws UnsupportedFlavorException, IOException { |
| if (flavor == null) { |
| throw new NullPointerException("flavor"); |
| } |
| |
| Transferable cntnts = getContents(null); |
| if (cntnts == null) { |
| throw new UnsupportedFlavorException(flavor); |
| } |
| return cntnts.getTransferData(flavor); |
| } |
| |
| |
| /** |
| * Registers the specified <code>FlavorListener</code> to receive |
| * <code>FlavorEvent</code>s from this clipboard. |
| * If <code>listener</code> is <code>null</code>, no exception |
| * is thrown and no action is performed. |
| * |
| * @param listener the listener to be added |
| * |
| * @see #removeFlavorListener |
| * @see #getFlavorListeners |
| * @see FlavorListener |
| * @see FlavorEvent |
| * @since 1.5 |
| */ |
| public synchronized void addFlavorListener(FlavorListener listener) { |
| if (listener == null) { |
| return; |
| } |
| if (flavorListeners == null) { |
| currentDataFlavors = getAvailableDataFlavorSet(); |
| flavorListeners = new EventListenerAggregate(FlavorListener.class); |
| } |
| flavorListeners.add(listener); |
| } |
| |
| /** |
| * Removes the specified <code>FlavorListener</code> so that it no longer |
| * receives <code>FlavorEvent</code>s from this <code>Clipboard</code>. |
| * This method performs no function, nor does it throw an exception, if |
| * the listener specified by the argument was not previously added to this |
| * <code>Clipboard</code>. |
| * If <code>listener</code> is <code>null</code>, no exception |
| * is thrown and no action is performed. |
| * |
| * @param listener the listener to be removed |
| * |
| * @see #addFlavorListener |
| * @see #getFlavorListeners |
| * @see FlavorListener |
| * @see FlavorEvent |
| * @since 1.5 |
| */ |
| public synchronized void removeFlavorListener(FlavorListener listener) { |
| if (listener == null || flavorListeners == null) { |
| return; |
| } |
| flavorListeners.remove(listener); |
| } |
| |
| /** |
| * Returns an array of all the <code>FlavorListener</code>s currently |
| * registered on this <code>Clipboard</code>. |
| * |
| * @return all of this clipboard's <code>FlavorListener</code>s or an empty |
| * array if no listeners are currently registered |
| * @see #addFlavorListener |
| * @see #removeFlavorListener |
| * @see FlavorListener |
| * @see FlavorEvent |
| * @since 1.5 |
| */ |
| public synchronized FlavorListener[] getFlavorListeners() { |
| return flavorListeners == null ? new FlavorListener[0] : |
| (FlavorListener[])flavorListeners.getListenersCopy(); |
| } |
| |
| /** |
| * Checks change of the <code>DataFlavor</code>s and, if necessary, |
| * notifies all listeners that have registered interest for notification |
| * on <code>FlavorEvent</code>s. |
| * |
| * @since 1.5 |
| */ |
| private void fireFlavorsChanged() { |
| if (flavorListeners == null) { |
| return; |
| } |
| Set prevDataFlavors = currentDataFlavors; |
| currentDataFlavors = getAvailableDataFlavorSet(); |
| if (prevDataFlavors.equals(currentDataFlavors)) { |
| return; |
| } |
| FlavorListener[] flavorListenerArray = |
| (FlavorListener[])flavorListeners.getListenersInternal(); |
| for (int i = 0; i < flavorListenerArray.length; i++) { |
| final FlavorListener listener = flavorListenerArray[i]; |
| EventQueue.invokeLater(new Runnable() { |
| public void run() { |
| listener.flavorsChanged(new FlavorEvent(Clipboard.this)); |
| } |
| }); |
| } |
| } |
| |
| /** |
| * Returns a set of <code>DataFlavor</code>s currently available |
| * on this clipboard. |
| * |
| * @return a set of <code>DataFlavor</code>s currently available |
| * on this clipboard |
| * |
| * @since 1.5 |
| */ |
| private Set getAvailableDataFlavorSet() { |
| Set set = new HashSet(); |
| Transferable contents = getContents(null); |
| if (contents != null) { |
| DataFlavor[] flavors = contents.getTransferDataFlavors(); |
| if (flavors != null) { |
| set.addAll(Arrays.asList(flavors)); |
| } |
| } |
| return set; |
| } |
| } |
