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package sun.awt.X11;

import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.DataFlavor;

import java.awt.dnd.DnDConstants;
import java.awt.dnd.InvalidDnDOperationException;

import java.util.Map;

An abstract class for drag protocols on X11 systems. Contains protocol-independent drag source code.
Since:1.5
/** * An abstract class for drag protocols on X11 systems. * Contains protocol-independent drag source code. * * @since 1.5 */
abstract class XDragSourceProtocol { private final XDragSourceProtocolListener listener; private boolean initialized = false; private long targetWindow = 0; private long targetProxyWindow = 0; private int targetProtocolVersion = 0; private long targetWindowMask = 0; // Always use the XAWT root window as the drag source window. static long getDragSourceWindow() { return XWindow.getXAWTRootWindow().getWindow(); } protected XDragSourceProtocol(XDragSourceProtocolListener listener) { if (listener == null) { throw new NullPointerException("Null XDragSourceProtocolListener"); } this.listener = listener; } protected final XDragSourceProtocolListener getProtocolListener() { return listener; }
Returns the protocol name. The protocol name cannot be null.
/** * Returns the protocol name. The protocol name cannot be null. */
public abstract String getProtocolName();
Initializes a drag operation with the specified supported drop actions, contents and data formats.
Params:
  • actions – a bitwise mask of DnDConstants that represent the supported drop actions.
  • contents – the contents for the drag operation.
  • formats – an array of Atoms that represent the supported data formats.
  • formats – an array of Atoms that represent the supported data formats.
Throws:
/** * Initializes a drag operation with the specified supported drop actions, * contents and data formats. * * @param actions a bitwise mask of {@code DnDConstants} that represent * the supported drop actions. * @param contents the contents for the drag operation. * @param formats an array of Atoms that represent the supported data formats. * @param formats an array of Atoms that represent the supported data formats. * @throws InvalidDnDOperationException if a drag operation is already * initialized. * @throws IllegalArgumentException if some argument has invalid value. * @throws XException if some X call failed. */
public final void initializeDrag(int actions, Transferable contents, Map<Long, DataFlavor> formatMap, long[] formats) throws InvalidDnDOperationException, IllegalArgumentException, XException { XToolkit.awtLock(); try { try { if (initialized) { throw new InvalidDnDOperationException("Already initialized"); } initializeDragImpl(actions, contents, formatMap, formats); initialized = true; } finally { if (!initialized) { cleanup(); } } } finally { XToolkit.awtUnlock(); } } /* The caller must hold AWT_LOCK. */ protected abstract void initializeDragImpl(int actions, Transferable contents, Map<Long, DataFlavor> formatMap, long[] formats) throws InvalidDnDOperationException, IllegalArgumentException, XException;
Terminates the current drag operation (if any) and resets the internal state of this object.
Throws:
  • XException – if some X call failed.
/** * Terminates the current drag operation (if any) and resets the internal * state of this object. * * @throws XException if some X call failed. */
public void cleanup() { initialized = false; cleanupTargetInfo(); }
Clears the information on the current drop target.
Throws:
  • XException – if some X call failed.
/** * Clears the information on the current drop target. * * @throws XException if some X call failed. */
public void cleanupTargetInfo() { targetWindow = 0; targetProxyWindow = 0; targetProtocolVersion = 0; }
Processes the specified client message event.
Returns:true if the event was successfully processed.
/** * Processes the specified client message event. * * @return true if the event was successfully processed. */
public abstract boolean processClientMessage(XClientMessageEvent xclient) throws XException; /* The caller must hold AWT_LOCK. */ public final boolean attachTargetWindow(long window, long time) { assert XToolkit.isAWTLockHeldByCurrentThread(); TargetWindowInfo info = getTargetWindowInfo(window); if (info == null) { return false; } else { targetWindow = window; targetProxyWindow = info.getProxyWindow(); targetProtocolVersion = info.getProtocolVersion(); return true; } } /* The caller must hold AWT_LOCK. */ public abstract TargetWindowInfo getTargetWindowInfo(long window); /* The caller must hold AWT_LOCK. */ public abstract void sendEnterMessage(long[] formats, int sourceAction, int sourceActions, long time); /* The caller must hold AWT_LOCK. */ public abstract void sendMoveMessage(int xRoot, int yRoot, int sourceAction, int sourceActions, long time); /* The caller must hold AWT_LOCK. */ public abstract void sendLeaveMessage(long time); /* The caller must hold AWT_LOCK. */ protected abstract void sendDropMessage(int xRoot, int yRoot, int sourceAction, int sourceActions, long time); public final void initiateDrop(int xRoot, int yRoot, int sourceAction, int sourceActions, long time) { XWindowAttributes wattr = new XWindowAttributes(); try { XErrorHandlerUtil.WITH_XERROR_HANDLER(XErrorHandler.IgnoreBadWindowHandler.getInstance()); int status = XlibWrapper.XGetWindowAttributes(XToolkit.getDisplay(), targetWindow, wattr.pData); XErrorHandlerUtil.RESTORE_XERROR_HANDLER(); if ((status == 0) || ((XErrorHandlerUtil.saved_error != null) && (XErrorHandlerUtil.saved_error.get_error_code() != XConstants.Success))) { throw new XException("XGetWindowAttributes failed"); } targetWindowMask = wattr.get_your_event_mask(); } finally { wattr.dispose(); } XErrorHandlerUtil.WITH_XERROR_HANDLER(XErrorHandler.IgnoreBadWindowHandler.getInstance()); XlibWrapper.XSelectInput(XToolkit.getDisplay(), targetWindow, targetWindowMask | XConstants.StructureNotifyMask); XErrorHandlerUtil.RESTORE_XERROR_HANDLER(); if ((XErrorHandlerUtil.saved_error != null) && (XErrorHandlerUtil.saved_error.get_error_code() != XConstants.Success)) { throw new XException("XSelectInput failed"); } sendDropMessage(xRoot, yRoot, sourceAction, sourceActions, time); } protected final void finalizeDrop() { XErrorHandlerUtil.WITH_XERROR_HANDLER(XErrorHandler.IgnoreBadWindowHandler.getInstance()); XlibWrapper.XSelectInput(XToolkit.getDisplay(), targetWindow, targetWindowMask); XErrorHandlerUtil.RESTORE_XERROR_HANDLER(); } public abstract boolean processProxyModeEvent(XClientMessageEvent xclient, long sourceWindow); protected final long getTargetWindow() { return targetWindow; } protected final long getTargetProxyWindow() { if (targetProxyWindow != 0) { return targetProxyWindow; } else { return targetWindow; } } protected final int getTargetProtocolVersion() { return targetProtocolVersion; } public static class TargetWindowInfo { private final long proxyWindow; private final int protocolVersion; public TargetWindowInfo(long proxy, int version) { proxyWindow = proxy; protocolVersion = version; } public long getProxyWindow() { return proxyWindow; } public int getProtocolVersion() { return protocolVersion; } } }