| /******************************************************************************* |
| * Copyright (c) 2000, 2003 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Common Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/cpl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.ui.views.navigator; |
| |
| import org.eclipse.core.runtime.*; |
| import org.eclipse.jface.viewers.ISelection; |
| import org.eclipse.swt.dnd.ByteArrayTransfer; |
| import org.eclipse.swt.dnd.TransferData; |
| import org.eclipse.ui.internal.ide.IDEWorkbenchPlugin; |
| |
| /** |
| * A LocalSelectionTransfer may be used for drag and drop operations |
| * within the same instance of Eclipse. |
| * The selection is made available directly for use in the DropTargetListener. |
| * dropAccept method. The DropTargetEvent passed to dropAccept does not contain |
| * the drop data. The selection may be used for validation purposes so that the |
| * drop can be aborted if appropriate. |
| * |
| * This class is not intended to be subclassed. |
| * |
| * @since 2.1 |
| */ |
| public class LocalSelectionTransfer extends ByteArrayTransfer { |
| |
| // First attempt to create a UUID for the type name to make sure that |
| // different Eclipse applications use different "types" of |
| // <code>LocalSelectionTransfer</code> |
| private static final String TYPE_NAME= "local-selection-transfer-format" + (new Long(System.currentTimeMillis())).toString(); //$NON-NLS-1$; |
| private static final int TYPEID= registerType(TYPE_NAME); |
| |
| private static final LocalSelectionTransfer INSTANCE= new LocalSelectionTransfer(); |
| |
| private ISelection selection; |
| |
| /** |
| * Only the singleton instance of this class may be used. |
| */ |
| private LocalSelectionTransfer() { |
| } |
| /** |
| * Returns the singleton. |
| */ |
| public static LocalSelectionTransfer getInstance() { |
| return INSTANCE; |
| } |
| /** |
| * Returns the local transfer data. |
| * |
| * @return the local transfer data |
| */ |
| public ISelection getSelection() { |
| return selection; |
| } |
| /** |
| * Tests whether native drop data matches this transfer type. |
| * |
| * @param result result of converting the native drop data to Java |
| * @return true if the native drop data does not match this transfer type. |
| * false otherwise. |
| */ |
| private boolean isInvalidNativeType(Object result) { |
| return !(result instanceof byte[]) || !TYPE_NAME.equals(new String((byte[])result)); |
| } |
| /** |
| * Returns the type id used to identify this transfer. |
| * |
| * @return the type id used to identify this transfer. |
| */ |
| protected int[] getTypeIds() { |
| return new int[] {TYPEID}; |
| } |
| /** |
| * Returns the type name used to identify this transfer. |
| * |
| * @return the type name used to identify this transfer. |
| */ |
| protected String[] getTypeNames(){ |
| return new String[] {TYPE_NAME}; |
| } |
| /** |
| * Overrides org.eclipse.swt.dnd.ByteArrayTransfer#javaToNative(Object, |
| * TransferData). |
| * Only encode the transfer type name since the selection is read and |
| * written in the same process. |
| * |
| * @see org.eclipse.swt.dnd.ByteArrayTransfer#javaToNative(java.lang.Object, org.eclipse.swt.dnd.TransferData) |
| */ |
| public void javaToNative(Object object, TransferData transferData) { |
| byte[] check= TYPE_NAME.getBytes(); |
| super.javaToNative(check, transferData); |
| } |
| /** |
| * Overrides org.eclipse.swt.dnd.ByteArrayTransfer#nativeToJava(TransferData). |
| * Test if the native drop data matches this transfer type. |
| * |
| * @see org.eclipse.swt.dnd.ByteArrayTransfer#nativeToJava(TransferData) |
| */ |
| public Object nativeToJava(TransferData transferData) { |
| Object result= super.nativeToJava(transferData); |
| if (isInvalidNativeType(result)) { |
| ILog log = IDEWorkbenchPlugin.getDefault().getLog(); |
| log.log( |
| new Status( |
| IStatus.ERROR, |
| IDEWorkbenchPlugin.IDE_WORKBENCH, |
| IStatus.ERROR, |
| ResourceNavigatorMessages.getString("LocalSelectionTransfer.errorMessage"), null)); //$NON-NLS-1$ |
| } |
| return selection; |
| } |
| /** |
| * Sets the transfer data for local use. |
| * |
| * @param s the transfer data |
| */ |
| public void setSelection(ISelection s) { |
| selection = s; |
| } |
| } |