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package sun.awt.X11;

import java.awt.datatransfer.Transferable;
import java.util.SortedMap;
import java.io.IOException;
import java.security.AccessController;
import java.util.HashMap;
import java.util.Map;
import sun.awt.UNIXToolkit;
import sun.awt.datatransfer.DataTransferer;
import sun.awt.datatransfer.SunClipboard;
import sun.awt.datatransfer.ClipboardTransferable;
import sun.security.action.GetIntegerAction;

A class which interfaces with the X11 selection service in order to support data transfer via Clipboard operations.
/** * A class which interfaces with the X11 selection service in order to support * data transfer via Clipboard operations. */
public final class XClipboard extends SunClipboard implements OwnershipListener { private final XSelection selection; // Time of calling XConvertSelection(). private long convertSelectionTime; // The flag used not to call XConvertSelection() if the previous SelectionNotify // has not been processed by checkChange(). private volatile boolean isSelectionNotifyProcessed; // The property in which the owner should place requested targets // when tracking changes of available data flavors (practically targets). private volatile XAtom targetsPropertyAtom; private static final Object classLock = new Object(); private static final int defaultPollInterval = 200; private static int pollInterval; private static Map<Long, XClipboard> targetsAtom2Clipboard;
Creates a system clipboard object.
/** * Creates a system clipboard object. */
public XClipboard(String name, String selectionName) { super(name); selection = new XSelection(XAtom.get(selectionName)); selection.registerOwershipListener(this); } /* * NOTE: This method may be called by privileged threads. * DO NOT INVOKE CLIENT CODE ON THIS THREAD! */ public void ownershipChanged(final boolean isOwner) { if (isOwner) { checkChangeHere(contents); } else { lostOwnershipImpl(); } } protected synchronized void setContentsNative(Transferable contents) { SortedMap formatMap = DataTransferer.getInstance().getFormatsForTransferable (contents, DataTransferer.adaptFlavorMap(getDefaultFlavorTable())); long[] formats = DataTransferer.keysToLongArray(formatMap); if (!selection.setOwner(contents, formatMap, formats, XToolkit.getCurrentServerTime())) { this.owner = null; this.contents = null; } } public long getID() { return selection.getSelectionAtom().getAtom(); } @Override public synchronized Transferable getContents(Object requestor) { if (contents != null) { return contents; } return new ClipboardTransferable(this); } /* Caller is synchronized on this. */ protected void clearNativeContext() { selection.reset(); } protected long[] getClipboardFormats() { return selection.getTargets(XToolkit.getCurrentServerTime()); } protected byte[] getClipboardData(long format) throws IOException { return selection.getData(format, XToolkit.getCurrentServerTime()); } private void checkChangeHere(Transferable contents) { if (areFlavorListenersRegistered()) { checkChange(DataTransferer.getInstance(). getFormatsForTransferableAsArray(contents, getDefaultFlavorTable())); } } private static int getPollInterval() { synchronized (XClipboard.classLock) { if (pollInterval <= 0) { pollInterval = AccessController.doPrivileged( new GetIntegerAction("awt.datatransfer.clipboard.poll.interval", defaultPollInterval)); if (pollInterval <= 0) { pollInterval = defaultPollInterval; } } return pollInterval; } } private XAtom getTargetsPropertyAtom() { if (null == targetsPropertyAtom) { targetsPropertyAtom = XAtom.get("XAWT_TARGETS_OF_SELECTION:" + selection.getSelectionAtom().getName()); } return targetsPropertyAtom; } protected void registerClipboardViewerChecked() { // for XConvertSelection() to be called for the first time in getTargetsDelayed() isSelectionNotifyProcessed = true; boolean mustSchedule = false; synchronized (XClipboard.classLock) { if (targetsAtom2Clipboard == null) { targetsAtom2Clipboard = new HashMap<Long, XClipboard>(2); } mustSchedule = targetsAtom2Clipboard.isEmpty(); targetsAtom2Clipboard.put(getTargetsPropertyAtom().getAtom(), this); if (mustSchedule) { XToolkit.addEventDispatcher(XWindow.getXAWTRootWindow().getWindow(), new SelectionNotifyHandler()); } } if (mustSchedule) { XToolkit.schedule(new CheckChangeTimerTask(), XClipboard.getPollInterval()); } } private static class CheckChangeTimerTask implements Runnable { public void run() { for (XClipboard clpbrd : targetsAtom2Clipboard.values()) { clpbrd.getTargetsDelayed(); } synchronized (XClipboard.classLock) { if (targetsAtom2Clipboard != null && !targetsAtom2Clipboard.isEmpty()) { XToolkit.schedule(this, XClipboard.getPollInterval()); } } } } private static class SelectionNotifyHandler implements XEventDispatcher { public void dispatchEvent(XEvent ev) { if (ev.get_type() == XConstants.SelectionNotify) { final XSelectionEvent xse = ev.get_xselection(); XClipboard clipboard = null; synchronized (XClipboard.classLock) { if (targetsAtom2Clipboard != null && !targetsAtom2Clipboard.isEmpty()) { XToolkit.removeEventDispatcher(XWindow.getXAWTRootWindow().getWindow(), this); return; } final long propertyAtom = xse.get_property(); clipboard = targetsAtom2Clipboard.get(propertyAtom); } if (null != clipboard) { clipboard.checkChange(xse); } } } } protected void unregisterClipboardViewerChecked() { isSelectionNotifyProcessed = false; synchronized (XClipboard.classLock) { targetsAtom2Clipboard.remove(getTargetsPropertyAtom().getAtom()); } } // checkChange() will be called on SelectionNotify private void getTargetsDelayed() { XToolkit.awtLock(); try { long curTime = System.currentTimeMillis(); if (isSelectionNotifyProcessed || curTime >= (convertSelectionTime + UNIXToolkit.getDatatransferTimeout())) { convertSelectionTime = curTime; XlibWrapper.XConvertSelection(XToolkit.getDisplay(), selection.getSelectionAtom().getAtom(), XDataTransferer.TARGETS_ATOM.getAtom(), getTargetsPropertyAtom().getAtom(), XWindow.getXAWTRootWindow().getWindow(), XConstants.CurrentTime); isSelectionNotifyProcessed = false; } } finally { XToolkit.awtUnlock(); } } /* * Tracks changes of available formats. * NOTE: This method may be called by privileged threads. * DO NOT INVOKE CLIENT CODE ON THIS THREAD! */ private void checkChange(XSelectionEvent xse) { final long propertyAtom = xse.get_property(); if (propertyAtom != getTargetsPropertyAtom().getAtom()) { // wrong atom return; } final XAtom selectionAtom = XAtom.get(xse.get_selection()); final XSelection changedSelection = XSelection.getSelection(selectionAtom); if (null == changedSelection || changedSelection != selection) { // unknown selection - do nothing return; } isSelectionNotifyProcessed = true; if (selection.isOwner()) { // selection is owner - do not need formats return; } long[] formats = null; if (propertyAtom == XConstants.None) { // We treat None property atom as "empty selection". formats = new long[0]; } else { WindowPropertyGetter targetsGetter = new WindowPropertyGetter(XWindow.getXAWTRootWindow().getWindow(), XAtom.get(propertyAtom), 0, XSelection.MAX_LENGTH, true, XConstants.AnyPropertyType); try { targetsGetter.execute(); formats = XSelection.getFormats(targetsGetter); } finally { targetsGetter.dispose(); } } checkChange(formats); } }