Java tutorial
/******************************************************************************* * Copyright (c) 2006, 2009 QNX Software Systems 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: * QNX Software Systems - initial API and implementation * Sergey Prigogin (Google) * Anton Leherbauer (Wind River Systems) * Markus Schorn (Wind River Systems) *******************************************************************************/ package org.eclipse.cdt.internal.ui.editor; import java.util.ArrayList; import java.util.List; import org.eclipse.core.runtime.Assert; import org.eclipse.jface.preference.IPreferenceStore; import org.eclipse.jface.preference.PreferenceConverter; import org.eclipse.jface.text.BadLocationException; import org.eclipse.jface.text.DocumentRewriteSession; import org.eclipse.jface.text.DocumentRewriteSessionType; import org.eclipse.jface.text.IDocument; import org.eclipse.jface.text.IDocumentExtension4; import org.eclipse.jface.text.IRegion; import org.eclipse.jface.text.ITextPresentationListener; import org.eclipse.jface.text.Region; import org.eclipse.jface.text.TextViewer; import org.eclipse.jface.text.contentassist.IContentAssistant; import org.eclipse.jface.text.information.IInformationPresenter; import org.eclipse.jface.text.source.IOverviewRuler; import org.eclipse.jface.text.source.IVerticalRuler; import org.eclipse.jface.text.source.SourceViewerConfiguration; import org.eclipse.jface.text.source.projection.ProjectionViewer; import org.eclipse.jface.util.IPropertyChangeListener; import org.eclipse.jface.util.PropertyChangeEvent; import org.eclipse.swt.SWT; import org.eclipse.swt.custom.StyleRange; import org.eclipse.swt.custom.StyledText; import org.eclipse.swt.graphics.Color; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.graphics.RGB; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Display; import org.eclipse.ui.texteditor.AbstractDecoratedTextEditorPreferenceConstants; import org.eclipse.ui.texteditor.AbstractTextEditor; import org.eclipse.cdt.ui.CUIPlugin; import org.eclipse.cdt.ui.PreferenceConstants; import org.eclipse.cdt.ui.text.CSourceViewerConfiguration; import org.eclipse.cdt.ui.text.ICColorConstants; import org.eclipse.cdt.ui.text.IColorManager; import org.eclipse.cdt.internal.ui.text.CTextTools; /** * Source viewer for C/C++ et al. */ public class CSourceViewer extends ProjectionViewer implements IPropertyChangeListener { /** Show outline operation id. */ public static final int SHOW_OUTLINE = 101; /** Show type hierarchy operation id. */ public static final int SHOW_HIERARCHY = 102; /** Show macro explorer operation id. */ public static final int SHOW_MACRO_EXPLORER = 103; /** Presents outline. */ private IInformationPresenter fOutlinePresenter; /** Presents type hierarchy. */ private IInformationPresenter fHierarchyPresenter; /** Presents macro explorer. */ private IInformationPresenter fMacroExplorationPresenter; /** * This viewer's foreground color. * @since 4.0 */ private Color fForegroundColor; /** * The viewer's background color. * @since 4.0 */ private Color fBackgroundColor; /** * This viewer's selection foreground color. * @since 4.0 */ private Color fSelectionForegroundColor; /** * The viewer's selection background color. * @since 4.0 */ private Color fSelectionBackgroundColor; /** * The preference store. * * @since 4.0 */ private IPreferenceStore fPreferenceStore; /** * Is this source viewer configured? * * @since 4.0 */ private boolean fIsConfigured; /** * Whether to delay setting the visual document until the projection has been computed. * <p> * Added for performance optimization. * </p> * @see #prepareDelayedProjection() * @since 4.0 */ private boolean fIsSetVisibleDocumentDelayed; /** * Whether projection mode was enabled when switching to segmented mode. * Workaround for https://bugs.eclipse.org/bugs/show_bug.cgi?id=195808 */ private boolean fWasProjectionMode; /** * The configured indent width. */ private int fIndentWidth = 4; /** * Flag indicating whether to use spaces exclusively for indentation. */ private boolean fUseSpaces; /** * Creates new source viewer. * @param parent * @param ruler * @param overviewRuler * @param isOverviewRulerShowing * @param styles * @param store */ public CSourceViewer(Composite parent, IVerticalRuler ruler, IOverviewRuler overviewRuler, boolean isOverviewRulerShowing, int styles, IPreferenceStore store) { super(parent, ruler, overviewRuler, isOverviewRulerShowing, styles); setPreferenceStore(store); } public IContentAssistant getContentAssistant() { return fContentAssistant; } /* * @see ISourceViewer#configure(SourceViewerConfiguration) */ @Override public void configure(SourceViewerConfiguration configuration) { // Prevent access to colors disposed in unconfigure(). StyledText textWidget = getTextWidget(); if (textWidget != null && !textWidget.isDisposed()) { Color foregroundColor = textWidget.getForeground(); if (foregroundColor != null && foregroundColor.isDisposed()) textWidget.setForeground(null); Color backgroundColor = textWidget.getBackground(); if (backgroundColor != null && backgroundColor.isDisposed()) textWidget.setBackground(null); } if (configuration instanceof CSourceViewerConfiguration) { CSourceViewerConfiguration cConfiguration = (CSourceViewerConfiguration) configuration; cConfiguration.resetScanners(); } super.configure(configuration); if (configuration instanceof CSourceViewerConfiguration) { CSourceViewerConfiguration cConfiguration = (CSourceViewerConfiguration) configuration; fOutlinePresenter = cConfiguration.getOutlinePresenter(this); if (fOutlinePresenter != null) fOutlinePresenter.install(this); fHierarchyPresenter = cConfiguration.getHierarchyPresenter(this); if (fHierarchyPresenter != null) fHierarchyPresenter.install(this); fMacroExplorationPresenter = cConfiguration.getMacroExplorationPresenter(this); if (fMacroExplorationPresenter != null) { fMacroExplorationPresenter.install(this); } String[] defaultIndentPrefixes = (String[]) fIndentChars.get(IDocument.DEFAULT_CONTENT_TYPE); if (defaultIndentPrefixes != null && defaultIndentPrefixes.length > 0) { final int indentWidth = cConfiguration.getIndentWidth(this); final boolean useSpaces = cConfiguration.useSpacesOnly(this); configureIndentation(indentWidth, useSpaces); } } if (fPreferenceStore != null) { fPreferenceStore.addPropertyChangeListener(this); initializeViewerColors(); // init flag here in case we start in segmented mode fWasProjectionMode = fPreferenceStore.getBoolean(PreferenceConstants.EDITOR_FOLDING_ENABLED); } fIsConfigured = true; } protected void initializeViewerColors() { if (fPreferenceStore != null) { StyledText styledText = getTextWidget(); // ----------- foreground color -------------------- Color color = fPreferenceStore.getBoolean(AbstractTextEditor.PREFERENCE_COLOR_FOREGROUND_SYSTEM_DEFAULT) ? null : createColor(fPreferenceStore, AbstractTextEditor.PREFERENCE_COLOR_FOREGROUND, styledText.getDisplay()); styledText.setForeground(color); if (fForegroundColor != null) fForegroundColor.dispose(); fForegroundColor = color; // ---------- background color ---------------------- color = fPreferenceStore.getBoolean(AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND_SYSTEM_DEFAULT) ? null : createColor(fPreferenceStore, AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND, styledText.getDisplay()); styledText.setBackground(color); if (fBackgroundColor != null) fBackgroundColor.dispose(); fBackgroundColor = color; // ----------- selection foreground color -------------------- color = fPreferenceStore.getBoolean( AbstractDecoratedTextEditorPreferenceConstants.EDITOR_SELECTION_FOREGROUND_DEFAULT_COLOR) ? null : createColor(fPreferenceStore, AbstractDecoratedTextEditorPreferenceConstants.EDITOR_SELECTION_FOREGROUND_COLOR, styledText.getDisplay()); styledText.setSelectionForeground(color); if (fSelectionForegroundColor != null) fSelectionForegroundColor.dispose(); fSelectionForegroundColor = color; // ---------- selection background color ---------------------- color = fPreferenceStore.getBoolean( AbstractDecoratedTextEditorPreferenceConstants.EDITOR_SELECTION_BACKGROUND_DEFAULT_COLOR) ? null : createColor(fPreferenceStore, AbstractDecoratedTextEditorPreferenceConstants.EDITOR_SELECTION_BACKGROUND_COLOR, styledText.getDisplay()); styledText.setSelectionBackground(color); if (fSelectionBackgroundColor != null) fSelectionBackgroundColor.dispose(); fSelectionBackgroundColor = color; } } /** * Creates a color from the information stored in the given preference store. * Returns <code>null</code> if there is no such information available. * * @param store the store to read from * @param key the key used for the lookup in the preference store * @param display the display used create the color * @return the created color according to the specification in the preference store */ private Color createColor(IPreferenceStore store, String key, Display display) { RGB rgb = null; if (store.contains(key)) { if (store.isDefault(key)) { rgb = PreferenceConverter.getDefaultColor(store, key); } else { rgb = PreferenceConverter.getColor(store, key); } if (rgb != null) return new Color(display, rgb); } return null; } /* * @see org.eclipse.jface.text.source.SourceViewer#unconfigure() */ @Override public void unconfigure() { if (fOutlinePresenter != null) { fOutlinePresenter.uninstall(); fOutlinePresenter = null; } if (fHierarchyPresenter != null) { fHierarchyPresenter.uninstall(); fHierarchyPresenter = null; } if (fMacroExplorationPresenter != null) { fMacroExplorationPresenter.uninstall(); fMacroExplorationPresenter = null; } if (fForegroundColor != null) { fForegroundColor.dispose(); fForegroundColor = null; } if (fBackgroundColor != null) { fBackgroundColor.dispose(); fBackgroundColor = null; } if (fPreferenceStore != null) fPreferenceStore.removePropertyChangeListener(this); super.unconfigure(); fIsConfigured = false; } /* * @see org.eclipse.jface.util.IPropertyChangeListener#propertyChange(org.eclipse.jface.util.PropertyChangeEvent) */ @Override public void propertyChange(PropertyChangeEvent event) { String property = event.getProperty(); if (AbstractTextEditor.PREFERENCE_COLOR_FOREGROUND.equals(property) || AbstractTextEditor.PREFERENCE_COLOR_FOREGROUND_SYSTEM_DEFAULT.equals(property) || AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND.equals(property) || AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND_SYSTEM_DEFAULT.equals(property) || AbstractDecoratedTextEditorPreferenceConstants.EDITOR_SELECTION_FOREGROUND_COLOR.equals(property) || AbstractDecoratedTextEditorPreferenceConstants.EDITOR_SELECTION_FOREGROUND_DEFAULT_COLOR .equals(property) || AbstractDecoratedTextEditorPreferenceConstants.EDITOR_SELECTION_BACKGROUND_COLOR.equals(property) || AbstractDecoratedTextEditorPreferenceConstants.EDITOR_SELECTION_BACKGROUND_DEFAULT_COLOR .equals(property)) { initializeViewerColors(); } } /** * Sets the preference store on this viewer. * * @param store the preference store * * @since 4.0 */ public void setPreferenceStore(IPreferenceStore store) { if (fIsConfigured && fPreferenceStore != null) fPreferenceStore.removePropertyChangeListener(this); fPreferenceStore = store; if (fIsConfigured && fPreferenceStore != null) { fPreferenceStore.addPropertyChangeListener(this); initializeViewerColors(); } } /* * @see org.eclipse.jface.text.source.SourceViewer#createControl(org.eclipse.swt.widgets.Composite, int) */ @Override protected void createControl(Composite parent, int styles) { // Use LEFT_TO_RIGHT unless otherwise specified. if ((styles & SWT.RIGHT_TO_LEFT) == 0 && (styles & SWT.LEFT_TO_RIGHT) == 0) styles |= SWT.LEFT_TO_RIGHT; super.createControl(parent, styles); } /* * @see org.eclipse.jface.text.ITextOperationTarget#doOperation(int) */ @Override public void doOperation(int operation) { if (getTextWidget() == null) { return; } switch (operation) { case SHOW_OUTLINE: fOutlinePresenter.showInformation(); return; case SHOW_HIERARCHY: fHierarchyPresenter.showInformation(); return; case SHOW_MACRO_EXPLORER: fMacroExplorationPresenter.showInformation(); } super.doOperation(operation); } /* * @see org.eclipse.jface.text.source.projection.ProjectionViewer#canDoOperation(int) */ @Override public boolean canDoOperation(int operation) { switch (operation) { case SHOW_OUTLINE: return fOutlinePresenter != null; case SHOW_HIERARCHY: return fHierarchyPresenter != null; case SHOW_MACRO_EXPLORER: return fMacroExplorationPresenter != null; } return super.canDoOperation(operation); } /** * Prepend given listener to the list of presentation listeners * * @param listener The listener to be added. * * @see TextViewer#addTextPresentationListener(ITextPresentationListener) * @since 4.0 */ public void prependTextPresentationListener(ITextPresentationListener listener) { Assert.isNotNull(listener); @SuppressWarnings("unchecked") // using list from base class List<ITextPresentationListener> textPresentationListeners = fTextPresentationListeners; if (textPresentationListeners == null) fTextPresentationListeners = textPresentationListeners = new ArrayList<ITextPresentationListener>(); textPresentationListeners.remove(listener); textPresentationListeners.add(0, listener); } /** * Delays setting the visual document until after the projection has been computed. * This method must only be called before the document is set on the viewer. * <p> * This is a performance optimization to reduce the computation of * the text presentation triggered by <code>setVisibleDocument(IDocument)</code>. * </p> * * @see #setVisibleDocument(IDocument) * @since 4.0 */ void prepareDelayedProjection() { Assert.isTrue(!fIsSetVisibleDocumentDelayed); fIsSetVisibleDocumentDelayed = true; } /** * {@inheritDoc} * <p> * This is a performance optimization to reduce the computation of * the text presentation triggered by {@link #setVisibleDocument(IDocument)} * </p> * @since 4.0 */ @Override protected void setVisibleDocument(IDocument document) { if (fIsSetVisibleDocumentDelayed) { fIsSetVisibleDocumentDelayed = false; IDocument previous = getVisibleDocument(); enableProjection(); // will set the visible document if anything is folded IDocument current = getVisibleDocument(); // if the visible document was not replaced, continue as usual if (current != null && current != previous) return; } super.setVisibleDocument(document); } /** * {@inheritDoc} * <p> * Performance optimization: since we know at this place * that none of the clients expects the given range to be * untouched we reuse the given range as return value. * </p> */ @Override protected StyleRange modelStyleRange2WidgetStyleRange(StyleRange range) { IRegion region = modelRange2WidgetRange(new Region(range.start, range.length)); if (region != null) { // don't clone the style range, but simply reuse it. range.start = region.getOffset(); range.length = region.getLength(); return range; } return null; } /* * @see org.eclipse.jface.text.source.projection.ProjectionViewer#setVisibleRegion(int, int) */ @Override public void setVisibleRegion(int start, int length) { // see https://bugs.eclipse.org/bugs/show_bug.cgi?id=195808 if (!fWasProjectionMode && isProjectionMode()) { fWasProjectionMode = true; } super.setVisibleRegion(start, length); } /* * @see org.eclipse.jface.text.source.projection.ProjectionViewer#resetVisibleRegion() */ @Override public void resetVisibleRegion() { super.resetVisibleRegion(); // see https://bugs.eclipse.org/bugs/show_bug.cgi?id=195808 if (fWasProjectionMode) { fWasProjectionMode = false; enableProjection(); } } /** * Configure the indentation mode for this viewer. * * @param indentWidth the indentation width * @param useSpaces if <code>true</code>, only spaces are used for indentation */ public void configureIndentation(int indentWidth, boolean useSpaces) { fIndentWidth = indentWidth; fUseSpaces = useSpaces; } /* * @see org.eclipse.jface.text.TextViewer#shift(boolean, boolean, boolean) */ @Override protected void shift(boolean useDefaultPrefixes, boolean right, boolean ignoreWhitespace) { if (!useDefaultPrefixes) { // simple shift case adjustIndent(right, fIndentWidth, fUseSpaces); return; } super.shift(useDefaultPrefixes, right, ignoreWhitespace); } /** * Increase/decrease indentation of current selection. * * @param increase if <code>true</code>, indent is increased by one unit * @param shiftWidth width in spaces of one indent unit * @param useSpaces if <code>true</code>, only spaces are used for indentation */ protected void adjustIndent(boolean increase, int shiftWidth, boolean useSpaces) { if (fUndoManager != null) { fUndoManager.beginCompoundChange(); } IDocument d = getDocument(); DocumentRewriteSession rewriteSession = null; try { if (d instanceof IDocumentExtension4) { IDocumentExtension4 extension = (IDocumentExtension4) d; rewriteSession = extension.startRewriteSession(DocumentRewriteSessionType.SEQUENTIAL); } Point selection = getSelectedRange(); // perform the adjustment int tabWidth = getTextWidget().getTabs(); int startLine = d.getLineOfOffset(selection.x); int endLine = selection.y == 0 ? startLine : d.getLineOfOffset(selection.x + selection.y - 1); for (int line = startLine; line <= endLine; ++line) { IRegion lineRegion = d.getLineInformation(line); String indent = IndentUtil.getCurrentIndent(d, line, false); int indentWidth = IndentUtil.computeVisualLength(indent, tabWidth); int newIndentWidth = Math.max(0, indentWidth + (increase ? shiftWidth : -shiftWidth)); String newIndent = IndentUtil.changePrefix(indent.trim(), newIndentWidth, tabWidth, useSpaces); int commonLen = getCommonPrefixLength(indent, newIndent); if (commonLen < Math.max(indent.length(), newIndent.length())) { if (commonLen > 0) { indent = indent.substring(commonLen); newIndent = newIndent.substring(commonLen); } final int offset = lineRegion.getOffset() + commonLen; if (!increase && newIndent.length() > indent.length() && indent.length() > 0) { d.replace(offset, indent.length(), ""); //$NON-NLS-1$ d.replace(offset, 0, newIndent); } else { d.replace(offset, indent.length(), newIndent); } } } } catch (BadLocationException e) { // ignored } finally { if (rewriteSession != null) { ((IDocumentExtension4) d).stopRewriteSession(rewriteSession); } if (fUndoManager != null) { fUndoManager.endCompoundChange(); } } } /** * Compute the length of the common prefix of two strings. * * @param s1 * @param s2 * @return the length of the common prefix */ private static int getCommonPrefixLength(String s1, String s2) { final int l1 = s1.length(); final int l2 = s2.length(); int i = 0; while (i < l1 && i < l2 && s1.charAt(i) == s2.charAt(i)) { ++i; } return i; } /* * work around for memory leak in TextViewer$WidgetCommand */ @Override protected void updateTextListeners(WidgetCommand cmd) { super.updateTextListeners(cmd); cmd.preservedText = null; cmd.event = null; cmd.text = null; } /** * Sets the viewer's background color to the given control's background color. * The background color is <em>only</em> set if it's visibly distinct from the * default Java source text color. * * @param control the control with the default background color */ public void adaptBackgroundColor(Control control) { // Workaround for dark editor background color, see https://bugs.eclipse.org/330680 Color defaultColor = control.getBackground(); float[] defaultBgHSB = defaultColor.getRGB().getHSB(); CTextTools textTools = CUIPlugin.getDefault().getTextTools(); IColorManager manager = textTools.getColorManager(); Color cDefaultColor = manager.getColor(ICColorConstants.C_DEFAULT); RGB cDefaultRGB = cDefaultColor != null ? cDefaultColor.getRGB() : new RGB(255, 255, 255); float[] cDefaultHSB = cDefaultRGB.getHSB(); if (Math.abs(defaultBgHSB[2] - cDefaultHSB[2]) >= 0.5f) { getTextWidget().setBackground(defaultColor); if (fBackgroundColor != null) { fBackgroundColor.dispose(); fBackgroundColor = null; } } } }