| /******************************************************************************* |
| * Copyright (c) 2000, 2009 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| * Tom Eicher (Avaloq Evolution AG) - block selection mode |
| *******************************************************************************/ |
| package org.eclipse.jface.text; |
| |
| import org.eclipse.core.runtime.Assert; |
| import org.eclipse.core.runtime.Platform; |
| |
| |
| /** |
| * Standard implementation of {@link org.eclipse.jface.text.ITextSelection}. |
| * <p> |
| * Takes advantage of the weak contract of correctness of its interface. If |
| * generated from a selection provider, it only remembers its offset and length |
| * and computes the remaining information on request.</p> |
| */ |
| public class TextSelection implements ITextSelection { |
| |
| /** |
| * Debug option for asserting valid offset and length. |
| * |
| * @since 3.5 |
| */ |
| private static final boolean ASSERT_INVLID_SELECTION_NULL= "true".equalsIgnoreCase(Platform.getDebugOption("org.eclipse.jface.text/assert/TextSelection/validConstructorArguments")); //$NON-NLS-1$ //$NON-NLS-2$ |
| |
| /** Internal empty text selection */ |
| private static final ITextSelection NULL= new TextSelection(); |
| |
| /** |
| * Returns the shared instance of the empty text selection. |
| * |
| * @return the shared instance of an empty text selection |
| */ |
| public static ITextSelection emptySelection() { |
| return NULL; |
| } |
| |
| /** Document which delivers the data of the selection, possibly <code>null</code>. */ |
| private final IDocument fDocument; |
| /** Offset of the selection */ |
| private int fOffset; |
| /** Length of the selection */ |
| private int fLength; |
| |
| |
| /** |
| * Creates an empty text selection. |
| */ |
| private TextSelection() { |
| fOffset= -1; |
| fLength= -1; |
| fDocument= null; |
| } |
| |
| /** |
| * Creates a text selection for the given range. This |
| * selection object describes generically a text range and |
| * is intended to be an argument for the <code>setSelection</code> |
| * method of selection providers. |
| * |
| * @param offset the offset of the range, must not be negative |
| * @param length the length of the range, must not be negative |
| */ |
| public TextSelection(int offset, int length) { |
| this(null, offset, length); |
| } |
| |
| /** |
| * Creates a text selection for the given range of the given document. |
| * This selection object is created by selection providers in responds |
| * <code>getSelection</code>. |
| * |
| * @param document the document whose text range is selected in a viewer |
| * @param offset the offset of the selected range, must not be negative |
| * @param length the length of the selected range, must not be negative |
| */ |
| public TextSelection(IDocument document, int offset, int length) { |
| if (ASSERT_INVLID_SELECTION_NULL) { |
| Assert.isLegal(offset >= 0); |
| Assert.isLegal(length >= 0); |
| } |
| fDocument= document; |
| fOffset= offset; |
| fLength= length; |
| } |
| |
| /** |
| * Tells whether this text selection is the empty selection. |
| * <p> |
| * A selection of length 0 is not an empty text selection as it |
| * describes, e.g., the cursor position in a viewer.</p> |
| * |
| * @return <code>true</code> if this selection is empty |
| * @see #emptySelection() |
| */ |
| @Override |
| public boolean isEmpty() { |
| return this == NULL || /* backwards compatibility: */ fOffset < 0 || fLength < 0; |
| } |
| |
| @Override |
| public int getOffset() { |
| return fOffset; |
| } |
| |
| @Override |
| public int getLength() { |
| return fLength; |
| } |
| |
| @Override |
| public int getStartLine() { |
| |
| try { |
| if (fDocument != null) |
| return fDocument.getLineOfOffset(fOffset); |
| } catch (BadLocationException x) { |
| // ignore |
| } |
| |
| return -1; |
| } |
| |
| @Override |
| public int getEndLine() { |
| try { |
| if (fDocument != null) { |
| int endOffset= fOffset + fLength; |
| if (fLength != 0) |
| endOffset--; |
| return fDocument.getLineOfOffset(endOffset); |
| } |
| } catch (BadLocationException x) { |
| // ignore |
| } |
| |
| return -1; |
| } |
| |
| @Override |
| public String getText() { |
| try { |
| if (fDocument != null) |
| return fDocument.get(fOffset, fLength); |
| } catch (BadLocationException x) { |
| // ignore |
| } |
| |
| return null; |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (obj == this) |
| return true; |
| |
| if (obj == null || getClass() != obj.getClass()) |
| return false; |
| |
| TextSelection s= (TextSelection) obj; |
| boolean sameRange= (s.fOffset == fOffset && s.fLength == fLength); |
| if (sameRange) { |
| |
| if (s.fDocument == null && fDocument == null) |
| return true; |
| if (s.fDocument == null || fDocument == null) |
| return false; |
| |
| try { |
| String sContent= s.fDocument.get(fOffset, fLength); |
| String content= fDocument.get(fOffset, fLength); |
| return sContent.equals(content); |
| } catch (BadLocationException x) { |
| // ignore |
| } |
| } |
| |
| return false; |
| } |
| |
| @Override |
| public int hashCode() { |
| int low= fDocument != null ? fDocument.hashCode() : 0; |
| return (fOffset << 24) | (fLength << 16) | low; |
| } |
| |
| /** |
| * Returns the document underlying the receiver, possibly <code>null</code>. |
| * |
| * @return the document underlying the receiver, possibly <code>null</code> |
| * @since 3.5 |
| */ |
| protected IDocument getDocument() { |
| return fDocument; |
| } |
| |
| @Override |
| public String toString() { |
| StringBuilder sb = new StringBuilder(); |
| sb.append("TextSelection [offset: ").append(fOffset); //$NON-NLS-1$ |
| int startLine = getStartLine(); |
| sb.append(", startLine: ").append(startLine); //$NON-NLS-1$ |
| int endLine = getEndLine(); |
| if (endLine != startLine) { |
| sb.append(", endLine: ").append(endLine); //$NON-NLS-1$ |
| } |
| sb.append(", length: ").append(fLength); //$NON-NLS-1$ |
| if (fLength != 0) { |
| sb.append(", text: ").append(getText()); //$NON-NLS-1$ |
| } |
| if (fDocument != null) { |
| sb.append(", document: ").append(fDocument); //$NON-NLS-1$ |
| } |
| sb.append("]"); //$NON-NLS-1$ |
| return sb.toString(); |
| } |
| } |
| |