Java tutorial
/******************************************************************************* * Copyright (c) 2008, 2012 Wind River Systems, Inc. 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: * Anton Leherbauer (Wind River Systems) - initial API and implementation *******************************************************************************/ package org.eclipse.cdt.internal.ui.text.c.hover; import org.eclipse.compare.CompareConfiguration; import org.eclipse.compare.contentmergeviewer.ITokenComparator; import org.eclipse.compare.rangedifferencer.IRangeComparator; import org.eclipse.jface.action.IToolBarManager; import org.eclipse.jface.resource.JFaceResources; import org.eclipse.jface.text.ITextPresentationListener; import org.eclipse.jface.text.TextPresentation; import org.eclipse.jface.text.TextViewer; import org.eclipse.swt.custom.StyleRange; import org.eclipse.swt.events.DisposeEvent; import org.eclipse.swt.graphics.Color; import org.eclipse.swt.graphics.RGB; import org.eclipse.swt.widgets.Composite; import org.eclipse.text.edits.ReplaceEdit; import org.eclipse.cdt.core.dom.rewrite.MacroExpansionExplorer.IMacroExpansionStep; import org.eclipse.cdt.internal.ui.compare.CMergeViewer; /** * A viewer for comparison of macro expansions. * * @since 5.0 */ class CMacroCompareViewer extends CMergeViewer { private static final RGB CHANGE_COLOR = new RGB(212, 212, 212); private class ReplaceEditsHighlighter implements ITextPresentationListener { private boolean fBefore; private int[] fStarts; private int[] fLengths; private Color fBackground; public ReplaceEditsHighlighter(Color background, boolean before) { fBackground = background; fBefore = before; } public void setReplaceEdits(int prefixLength, ReplaceEdit[] edits) { fStarts = new int[edits.length]; fLengths = new int[edits.length]; int delta = 0; for (int i = 0; i < edits.length; i++) { ReplaceEdit edit = edits[i]; fStarts[i] = prefixLength + edit.getOffset() + delta; fLengths[i] = fBefore ? edit.getLength() : edit.getText().length(); if (!fBefore) { delta += edit.getText().length() - edit.getLength(); } } } /* * @see org.eclipse.jface.text.ITextPresentationListener#applyTextPresentation(org.eclipse.jface.text.TextPresentation) */ @Override public void applyTextPresentation(TextPresentation textPresentation) { for (int i = 0; i < fStarts.length; i++) { textPresentation.mergeStyleRange(new StyleRange(fStarts[i], fLengths[i], null, fBackground)); } } } /** * A dummy {@link ITokenComparator}. */ private static class NullTokenComparator implements ITokenComparator { @Override public int getTokenLength(int index) { return 0; } @Override public int getTokenStart(int index) { return 0; } @Override public int getRangeCount() { return 0; } @Override public boolean rangesEqual(int thisIndex, IRangeComparator other, int otherIndex) { return true; } @Override public boolean skipRangeComparison(int length, int maxLength, IRangeComparator other) { return true; } } private final ReplaceEditsHighlighter fLeftHighlighter; private final ReplaceEditsHighlighter fRightHighlighter; private Color fChangeBackground; private TextViewer fLeftViewer; private TextViewer fRightViewer; private TextViewer fTopViewer; private int fViewerIndex; private CMacroExpansionInput fInput; private int fStepIndex; private int fPrefixLength; public CMacroCompareViewer(Composite parent, int styles, CompareConfiguration mp) { super(parent, styles, mp); fChangeBackground = new Color(parent.getDisplay(), CHANGE_COLOR); fLeftHighlighter = new ReplaceEditsHighlighter(fChangeBackground, true); fRightHighlighter = new ReplaceEditsHighlighter(fChangeBackground, false); fViewerIndex = 0; } /* * @see org.eclipse.cdt.internal.ui.compare.AbstractMergeViewer#handleDispose(org.eclipse.swt.events.DisposeEvent) */ @Override protected void handleDispose(DisposeEvent event) { if (fLeftViewer != null) { fLeftViewer.removeTextPresentationListener(fLeftHighlighter); } if (fRightViewer != null) { fRightViewer.removeTextPresentationListener(fRightHighlighter); } fChangeBackground.dispose(); super.handleDispose(event); } @Override protected IToolBarManager getToolBarManager(Composite parent) { // no toolbar return null; } /* * @see org.eclipse.cdt.internal.ui.compare.AbstractMergeViewer#configureTextViewer(org.eclipse.jface.text.TextViewer) */ @Override protected void configureTextViewer(TextViewer textViewer) { super.configureTextViewer(textViewer); // hack: gain access to text viewers switch (fViewerIndex++) { case 0: fTopViewer = textViewer; fTopViewer.getTextWidget().setFont(JFaceResources.getFont(CMergeViewer.class.getName())); break; case 1: fLeftViewer = textViewer; fLeftViewer.getTextWidget().setFont(JFaceResources.getFont(CMergeViewer.class.getName())); fLeftViewer.addTextPresentationListener(fLeftHighlighter); break; case 2: fRightViewer = textViewer; fRightViewer.getTextWidget().setFont(JFaceResources.getFont(CMergeViewer.class.getName())); fRightViewer.addTextPresentationListener(fRightHighlighter); } } /* * @see org.eclipse.compare.contentmergeviewer.TextMergeViewer#createTokenComparator(java.lang.String) */ @Override protected ITokenComparator createTokenComparator(String line) { return new NullTokenComparator(); } /** * Set the macro expansion input. * * @param input */ public void setMacroExpansionInput(CMacroExpansionInput input) { fInput = input; fPrefixLength = 0; } /* * @see org.eclipse.jface.viewers.ContentViewer#setInput(java.lang.Object) */ @Override public void setInput(Object input) { boolean redraw = true; if (fLeftViewer != null && fRightViewer != null) { redraw = false; fLeftViewer.setRedraw(false); fRightViewer.setRedraw(false); } ReplaceEdit[] edits = null; try { if (fInput != null) { final IMacroExpansionStep step; if (fStepIndex < fInput.fExplorer.getExpansionStepCount()) { step = fInput.fExplorer.getExpansionStep(fStepIndex); } else { step = fInput.fExplorer.getFullExpansion(); } edits = step.getReplacements(); fLeftHighlighter.setReplaceEdits(fPrefixLength, edits); fRightHighlighter.setReplaceEdits(fPrefixLength, edits); } super.setInput(input); } finally { if (!redraw && fLeftViewer != null && fRightViewer != null) { fLeftViewer.setRedraw(true); fRightViewer.setRedraw(true); } } if (edits != null && edits.length > 0) { if (fLeftViewer != null && fRightViewer != null) { final int firstDiffOffset = fPrefixLength + edits[0].getOffset(); fLeftViewer.revealRange(firstDiffOffset, edits[0].getLength()); fRightViewer.revealRange(firstDiffOffset, edits[0].getText().length()); } } } public void setMacroExpansionStep(int index) { fStepIndex = index; } }