Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2008 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) *******************************************************************************/ package org.eclipse.cdt.internal.ui.preferences.formatter; import java.util.HashMap; import java.util.Iterator; import java.util.Map; import java.util.Observable; import org.eclipse.core.resources.IProject; import org.eclipse.core.runtime.IConfigurationElement; import org.eclipse.core.runtime.IExtension; import org.eclipse.core.runtime.IExtensionPoint; import org.eclipse.core.runtime.Platform; import org.eclipse.core.runtime.preferences.IEclipsePreferences; import org.eclipse.core.runtime.preferences.IScopeContext; import org.eclipse.jface.resource.JFaceResources; import org.eclipse.swt.SWT; import org.eclipse.swt.events.SelectionAdapter; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.widgets.Combo; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.ui.PlatformUI; import org.eclipse.cdt.core.CCorePlugin; import org.eclipse.cdt.core.CCorePreferenceConstants; import org.eclipse.cdt.ui.CUIPlugin; import org.eclipse.cdt.utils.ui.controls.ControlFactory; import org.eclipse.cdt.internal.ui.ICHelpContextIds; import org.eclipse.cdt.internal.ui.preferences.PreferencesAccess; /** * Allows to choose the formatter in a combo box. * If no formatter is contributed, nothing is shown. */ public class CustomCodeFormatterBlock extends Observable { private HashMap<String, String> idMap = new HashMap<String, String>(); private IEclipsePreferences fPrefs; private String fDefaultFormatterId; private Combo fFormatterCombo; private static final String ATTR_NAME = "name"; //$NON-NLS-1$ private static final String ATTR_ID = "id"; //$NON-NLS-1$ private static final String DEFAULT = FormatterMessages.CustomCodeFormatterBlock_default_formatter; public CustomCodeFormatterBlock(IProject project, PreferencesAccess access) { final IScopeContext scope; final IEclipsePreferences defaults; if (project != null) { scope = access.getProjectScope(project); defaults = access.getInstanceScope().getNode(CCorePlugin.PLUGIN_ID); } else { scope = access.getInstanceScope(); defaults = access.getDefaultScope().getNode(CCorePlugin.PLUGIN_ID); } fPrefs = scope.getNode(CCorePlugin.PLUGIN_ID); fDefaultFormatterId = defaults.get(CCorePreferenceConstants.CODE_FORMATTER, null); if (fDefaultFormatterId == null) { // backward compatibility: use UI prefs IEclipsePreferences instance = access.getInstanceScope().getNode(CUIPlugin.PLUGIN_ID); fDefaultFormatterId = instance.get(CCorePreferenceConstants.CODE_FORMATTER, null); if (fDefaultFormatterId != null) { instance.remove(CCorePreferenceConstants.CODE_FORMATTER); if (project != null) { defaults.put(CCorePreferenceConstants.CODE_FORMATTER, fDefaultFormatterId); } } } initializeFormatters(); } public void performOk() { if (fFormatterCombo == null) { return; } String text = fFormatterCombo.getText(); String formatterId = idMap.get(text); if (formatterId != null && !formatterId.equals(fDefaultFormatterId)) { fPrefs.put(CCorePreferenceConstants.CODE_FORMATTER, formatterId); } else { // simply reset to the default one. performDefaults(); } } public void performDefaults() { fPrefs.remove(CCorePreferenceConstants.CODE_FORMATTER); if (fFormatterCombo == null) { return; } fFormatterCombo.clearSelection(); fFormatterCombo.setText(DEFAULT); Iterator<Map.Entry<String, String>> iterator = idMap.entrySet().iterator(); while (iterator.hasNext()) { Map.Entry<String, String> entry = iterator.next(); String val = entry.getValue(); if (val != null && val.equals(fDefaultFormatterId)) { fFormatterCombo.setText(entry.getKey()); } } handleFormatterChanged(); } /** * Get the currently selected formatter id. * * @return the selected formatter id or <code>null</code> if the default is selected. */ public String getFormatterId() { if (fFormatterCombo == null) { return fPrefs.get(CCorePreferenceConstants.CODE_FORMATTER, fDefaultFormatterId); } String formatterId = idMap.get(fFormatterCombo.getText()); return formatterId; } /* (non-Javadoc) * @see org.eclipse.jface.dialogs.IDialogPage#createControl(org.eclipse.swt.widgets.Composite) */ public Control createContents(Composite parent) { if (getNumberOfAvailableFormatters() == 0) { return parent; } Composite composite = ControlFactory.createGroup(parent, FormatterMessages.CustomCodeFormatterBlock_formatter_name, 1); ((GridData) composite.getLayoutData()).horizontalSpan = 5; PlatformUI.getWorkbench().getHelpSystem().setHelp(composite, ICHelpContextIds.CODEFORMATTER_PREFERENCE_PAGE); fFormatterCombo = new Combo(composite, SWT.DROP_DOWN | SWT.READ_ONLY); fFormatterCombo.setFont(parent.getFont()); fFormatterCombo.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); fFormatterCombo.addSelectionListener(new SelectionAdapter() { @Override public void widgetSelected(SelectionEvent e) { handleFormatterChanged(); } }); Iterator<String> items = idMap.keySet().iterator(); while (items.hasNext()) { fFormatterCombo.add(items.next()); } final String noteTitle = FormatterMessages.CustomCodeFormatterBlock_formatter_note; final String noteMessage = FormatterMessages.CustomCodeFormatterBlock_contributed_formatter_warning; ControlFactory.createNoteComposite(JFaceResources.getDialogFont(), composite, noteTitle, noteMessage); initDefault(); return composite; } private void handleFormatterChanged() { setChanged(); String formatterId = getFormatterId(); notifyObservers(formatterId); } private void initDefault() { boolean init = false; String formatterID = fPrefs.get(CCorePreferenceConstants.CODE_FORMATTER, fDefaultFormatterId); if (formatterID != null) { Iterator<Map.Entry<String, String>> iterator = idMap.entrySet().iterator(); while (iterator.hasNext()) { Map.Entry<String, String> entry = iterator.next(); String val = entry.getValue(); if (val != null && val.equals(formatterID)) { fFormatterCombo.setText(entry.getKey()); init = true; } } } if (!init) { formatterID = null; fFormatterCombo.setText(DEFAULT); } } private void initializeFormatters() { idMap = new HashMap<String, String>(); idMap.put(DEFAULT, CCorePreferenceConstants.DEFAULT_CODE_FORMATTER); IExtensionPoint point = Platform.getExtensionRegistry().getExtensionPoint(CCorePlugin.PLUGIN_ID, CCorePlugin.FORMATTER_EXTPOINT_ID); if (point != null) { IExtension[] exts = point.getExtensions(); for (IExtension ext : exts) { IConfigurationElement[] elements = ext.getConfigurationElements(); for (int j = 0; j < elements.length; ++j) { String name = elements[j].getAttribute(ATTR_NAME); String id = elements[j].getAttribute(ATTR_ID); idMap.put(name, id); } } } } private final int getNumberOfAvailableFormatters() { return idMap.size() - 1; } }