Java tutorial
/******************************************************************************* * Copyright (c) 2005, 2006 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 *******************************************************************************/ package descent.internal.ui.text.java; import java.net.URL; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import org.eclipse.core.runtime.FileLocator; import org.eclipse.core.runtime.IConfigurationElement; import org.eclipse.core.runtime.IExtension; import org.eclipse.core.runtime.IStatus; import org.eclipse.core.runtime.InvalidRegistryObjectException; import org.eclipse.core.runtime.Path; import org.eclipse.core.runtime.Platform; import org.eclipse.core.runtime.Status; import org.eclipse.core.runtime.SubProgressMonitor; import org.eclipse.jface.action.LegacyActionTools; import org.eclipse.jface.resource.ImageDescriptor; import descent.internal.corext.util.Messages; import descent.ui.text.java.ContentAssistInvocationContext; import descent.ui.text.java.IJavaCompletionProposalComputer; import descent.internal.ui.JavaPlugin; import org.osgi.framework.Bundle; /** * Describes a category extension to the "javaCompletionProposalComputer" extension point. * * @since 3.2 */ public final class CompletionProposalCategory { /** The extension schema name of the icon attribute. */ private static final String ICON = "icon"; //$NON-NLS-1$ private final String fId; private final String fName; private final IConfigurationElement fElement; /** The image descriptor for this category, or <code>null</code> if none specified. */ private final ImageDescriptor fImage; private boolean fIsSeparateCommand = true; private boolean fIsEnabled = true; private boolean fIsIncluded = true; private final CompletionProposalComputerRegistry fRegistry; private int fSortOrder = 0x10000; private String fLastError = null; CompletionProposalCategory(IConfigurationElement element, CompletionProposalComputerRegistry registry) { fElement = element; fRegistry = registry; IExtension parent = (IExtension) element.getParent(); fId = parent.getUniqueIdentifier(); checkNotNull(fId, "id"); //$NON-NLS-1$ String name = parent.getLabel(); if (name == null) fName = fId; else fName = name; String icon = element.getAttribute(ICON); ImageDescriptor img = null; if (icon != null) { Bundle bundle = getBundle(); if (bundle != null) { Path path = new Path(icon); URL url = FileLocator.find(bundle, path, null); img = ImageDescriptor.createFromURL(url); } } fImage = img; } CompletionProposalCategory(String id, String name, CompletionProposalComputerRegistry registry) { fRegistry = registry; fId = id; fName = name; fElement = null; fImage = null; } private Bundle getBundle() { String namespace = fElement.getDeclaringExtension().getContributor().getName(); Bundle bundle = Platform.getBundle(namespace); return bundle; } /** * Checks an element that must be defined according to the extension * point schema. Throws an * <code>InvalidRegistryObjectException</code> if <code>obj</code> * is <code>null</code>. */ private void checkNotNull(Object obj, String attribute) throws InvalidRegistryObjectException { if (obj == null) { Object[] args = { getId(), fElement.getContributor().getName(), attribute }; String message = Messages .format(JavaTextMessages.CompletionProposalComputerDescriptor_illegal_attribute_message, args); IStatus status = new Status(IStatus.WARNING, JavaPlugin.getPluginId(), IStatus.OK, message, null); JavaPlugin.log(status); throw new InvalidRegistryObjectException(); } } /** * Returns the identifier of the described extension. * * @return Returns the id */ public String getId() { return fId; } /** * Returns the name of the described extension. * * @return Returns the name */ public String getName() { return fName; } /** * Returns the name of the described extension * without mnemonic hint in order to be displayed * in a message. * * @return Returns the name */ public String getDisplayName() { return LegacyActionTools.removeMnemonics(fName); } /** * Returns the image descriptor of the described category. * * @return the image descriptor of the described category */ public ImageDescriptor getImageDescriptor() { return fImage; } /** * Sets the separate command state of the category. * * @param enabled the new enabled state. */ public void setSeparateCommand(boolean enabled) { fIsSeparateCommand = enabled; } /** * Returns the enablement state of the category. * * @return the enablement state of the category */ public boolean isSeparateCommand() { return fIsSeparateCommand; } /** * @param included the included */ public void setIncluded(boolean included) { fIsIncluded = included; } /** * @return included */ public boolean isIncluded() { return fIsIncluded; } public boolean isEnabled() { return fIsEnabled; } public void setEnabled(boolean isEnabled) { fIsEnabled = isEnabled; } /** * Returns <code>true</code> if the category contains any computers, <code>false</code> * otherwise. * * @return <code>true</code> if the category contains any computers, <code>false</code> * otherwise */ public boolean hasComputers() { List descriptors = fRegistry.getProposalComputerDescriptors(); for (Iterator it = descriptors.iterator(); it.hasNext();) { CompletionProposalComputerDescriptor desc = (CompletionProposalComputerDescriptor) it.next(); if (desc.getCategory() == this) return true; } return false; } /** * Returns <code>true</code> if the category contains any computers in the given partition, <code>false</code> * otherwise. * * @param partition the partition * @return <code>true</code> if the category contains any computers, <code>false</code> * otherwise */ public boolean hasComputers(String partition) { List descriptors = fRegistry.getProposalComputerDescriptors(partition); for (Iterator it = descriptors.iterator(); it.hasNext();) { CompletionProposalComputerDescriptor desc = (CompletionProposalComputerDescriptor) it.next(); if (desc.getCategory() == this) return true; } return false; } /** * @return sortOrder */ public int getSortOrder() { return fSortOrder; } /** * @param sortOrder the sortOrder */ public void setSortOrder(int sortOrder) { fSortOrder = sortOrder; } /** * Safely computes completion proposals of all computers of this category through their * extension. If an extension is disabled, throws an exception or otherwise does not adhere to * the contract described in {@link IJavaCompletionProposalComputer}, it is disabled. * * @param context the invocation context passed on to the extension * @param partition the partition type where to invocation occurred * @param monitor the progress monitor passed on to the extension * @return the list of computed completion proposals (element type: * {@link org.eclipse.jface.text.contentassist.ICompletionProposal}) */ public List computeCompletionProposals(ContentAssistInvocationContext context, String partition, SubProgressMonitor monitor) { fLastError = null; List result = new ArrayList(); List descriptors = new ArrayList(fRegistry.getProposalComputerDescriptors(partition)); for (Iterator it = descriptors.iterator(); it.hasNext();) { CompletionProposalComputerDescriptor desc = (CompletionProposalComputerDescriptor) it.next(); if (desc.getCategory() == this) result.addAll(desc.computeCompletionProposals(context, monitor)); if (fLastError == null) fLastError = desc.getErrorMessage(); } return result; } /** * Safely computes context information objects of all computers of this category through their * extension. If an extension is disabled, throws an exception or otherwise does not adhere to * the contract described in {@link IJavaCompletionProposalComputer}, it is disabled. * * @param context the invocation context passed on to the extension * @param partition the partition type where to invocation occurred * @param monitor the progress monitor passed on to the extension * @return the list of computed context information objects (element type: * {@link org.eclipse.jface.text.contentassist.IContextInformation}) */ public List computeContextInformation(ContentAssistInvocationContext context, String partition, SubProgressMonitor monitor) { fLastError = null; List result = new ArrayList(); List descriptors = new ArrayList(fRegistry.getProposalComputerDescriptors(partition)); for (Iterator it = descriptors.iterator(); it.hasNext();) { CompletionProposalComputerDescriptor desc = (CompletionProposalComputerDescriptor) it.next(); if (desc.getCategory() == this) result.addAll(desc.computeContextInformation(context, monitor)); if (fLastError == null) fLastError = desc.getErrorMessage(); } return result; } /** * Returns the error message from the computers in this category. * * @return the error message from the computers in this category */ public String getErrorMessage() { return fLastError; } /** * Notifies the computers in this category of a proposal computation session start. */ public void sessionStarted() { List descriptors = new ArrayList(fRegistry.getProposalComputerDescriptors()); for (Iterator it = descriptors.iterator(); it.hasNext();) { CompletionProposalComputerDescriptor desc = (CompletionProposalComputerDescriptor) it.next(); if (desc.getCategory() == this) desc.sessionStarted(); if (fLastError == null) fLastError = desc.getErrorMessage(); } } /** * Notifies the computers in this category of a proposal computation session end. */ public void sessionEnded() { List descriptors = new ArrayList(fRegistry.getProposalComputerDescriptors()); for (Iterator it = descriptors.iterator(); it.hasNext();) { CompletionProposalComputerDescriptor desc = (CompletionProposalComputerDescriptor) it.next(); if (desc.getCategory() == this) desc.sessionEnded(); if (fLastError == null) fLastError = desc.getErrorMessage(); } } }