org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/java/ProposalSorterHandle.java - jdt/eclipse.jdt.ui - Git at Google

 /*******************************************************************************
  * 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 org.eclipse.jdt.internal.ui.text.java;

 import java.util.Collections;
 import java.util.List;

 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IConfigurationElement;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.InvalidRegistryObjectException;
 import org.eclipse.core.runtime.PerformanceStats;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.core.runtime.Status;

 import org.eclipse.jface.text.Assert;

 import org.eclipse.jdt.internal.corext.util.Messages;

 import org.eclipse.jdt.ui.text.java.AbstractProposalSorter;
 import org.eclipse.jdt.ui.text.java.ContentAssistInvocationContext;

 import org.eclipse.jdt.internal.ui.JavaPlugin;

 import org.osgi.framework.Bundle;

 /**
  * The description of an extension to the
  * <code>org.eclipse.jdt.ui.javaCompletionProposalSorters</code> extension point. Instances are
  * immutable.
  *
  * @since 3.2
  */
 public final class ProposalSorterHandle {
 	/** The extension schema name of the id attribute. */
 	private static final String ID= "id"; //$NON-NLS-1$
 	/** The extension schema name of the name attribute. */
 	private static final String NAME= "name"; //$NON-NLS-1$
 	/** The extension schema name of the class attribute. */
 	private static final String CLASS= "class"; //$NON-NLS-1$
 	/** The extension schema name of the activate attribute. */
 	private static final String ACTIVATE= "activate"; //$NON-NLS-1$
 	/** The name of the performance event used to trace extensions. */
 	private static final String PERFORMANCE_EVENT= JavaPlugin.getPluginId() + "/perf/content_assist_sorters/extensions"; //$NON-NLS-1$
 	/**
 	 * If <code>true</code>, execution time of extensions is measured and extensions may be
 	 * disabled if execution takes too long.
 	 */
 	private static final boolean MEASURE_PERFORMANCE= PerformanceStats.isEnabled(PERFORMANCE_EVENT);
 	/** The one and only operation name. */
 	private static final String SORT= "sort"; //$NON-NLS-1$

 	/** The identifier of the extension. */
 	private final String fId;
 	/** The name of the extension. */
 	private final String fName;
 	/** The class name of the provided <code>AbstractProposalSorter</code>. */
 	private final String fClass;
 	/** The activate attribute value. */
 	private final boolean fActivate;
 	/** The configuration element of this extension. */
 	private final IConfigurationElement fElement;
 	/** The computer, if instantiated, <code>null</code> otherwise. */
 	private AbstractProposalSorter fSorter;

 	/**
 	 * Creates a new descriptor.
 	 *
 	 * @param element the configuration element to read
 	 * @throws InvalidRegistryObjectException if the configuration element is not valid any longer
 	 *         or does not contain mandatory attributes
 	 */
 	ProposalSorterHandle(IConfigurationElement element) throws InvalidRegistryObjectException {
 		Assert.isLegal(element != null);

 		fElement= element;
 		fId= element.getAttribute(ID);
 		checkNotNull(fId, ID);

 		String name= element.getAttribute(NAME);
 		if (name == null)
 			fName= fId;
 		else
 			fName= name;

 		String activateAttribute= element.getAttribute(ACTIVATE);
 		fActivate= Boolean.valueOf(activateAttribute).booleanValue();

 		fClass= element.getAttribute(CLASS);
 		checkNotNull(fClass, CLASS);
 	}

 	/**
 	 * 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 a cached instance of the sorter as described in the extension's xml. The sorter is
 	 * {@link #createSorter() created} the first time that this method is called and then cached.
 	 *
 	 * @return a new instance of the proposal sorter as described by this descriptor
 	 * @throws CoreException if the creation fails
 	 * @throws InvalidRegistryObjectException if the extension is not valid any longer (e.g. due to
 	 *         plug-in unloading)
 	 */
 	private synchronized AbstractProposalSorter getSorter() throws CoreException, InvalidRegistryObjectException {
 		if (fSorter == null && (fActivate || isPluginLoaded()))
 			fSorter= createSorter();
 		return fSorter;
 	}

 	private boolean isPluginLoaded() throws InvalidRegistryObjectException {
 		Bundle bundle= getBundle();
 		return bundle != null && bundle.getState() == Bundle.ACTIVE;
 	}

 	private Bundle getBundle() throws InvalidRegistryObjectException {
 		String symbolicName= fElement.getContributor().getName();
 		Bundle bundle= Platform.getBundle(symbolicName);
 		return bundle;
 	}

 	/**
 	 * Returns a new instance of the sorter as described in the
 	 * extension's xml.
 	 *
 	 * @return a new instance of the completion proposal computer as
 	 *         described by this descriptor
 	 * @throws CoreException if the creation fails
 	 * @throws InvalidRegistryObjectException if the extension is not
 	 *         valid any longer (e.g. due to plug-in unloading)
 	 */
 	private AbstractProposalSorter createSorter() throws CoreException, InvalidRegistryObjectException {
 		return (AbstractProposalSorter) fElement.createExecutableExtension(CLASS);
 	}

 	/**
 	 * Safely computes completion proposals through the described extension. If the extension throws
 	 * an exception or otherwise does not adhere to the contract described in
 	 * {@link AbstractProposalSorter}, the list is returned as is.
 	 *
 	 * @param context the invocation context passed on to the extension
 	 * @param proposals the list of computed completion proposals to be sorted (element type:
 	 *        {@link org.eclipse.jface.text.contentassist.ICompletionProposal}), must be writable
 	 */
 	public void sortProposals(ContentAssistInvocationContext context, List proposals) {
 		IStatus status;
 		try {
 			AbstractProposalSorter sorter= getSorter();

 			PerformanceStats stats= startMeter(SORT, sorter);

 			sorter.beginSorting(context);
 			Collections.sort(proposals, sorter);
 			sorter.endSorting();

 			status= stopMeter(stats, SORT);

 			// valid result
 			if (status == null)
 				return;

 			status= createAPIViolationStatus(SORT);

 		} catch (InvalidRegistryObjectException x) {
 			status= createExceptionStatus(x);
 		} catch (CoreException x) {
 			status= createExceptionStatus(x);
 		} catch (RuntimeException x) {
 			status= createExceptionStatus(x);
 		}

 		JavaPlugin.log(status);
 		return;
 	}

 	private IStatus stopMeter(final PerformanceStats stats, String operation) {
 		if (MEASURE_PERFORMANCE) {
 			stats.endRun();
 			if (stats.isFailure())
 				return createPerformanceStatus(operation);
 		}
 		return null;
 	}

 	private PerformanceStats startMeter(String context, AbstractProposalSorter sorter) {
 		final PerformanceStats stats;
 		if (MEASURE_PERFORMANCE) {
 			stats= PerformanceStats.getStats(PERFORMANCE_EVENT, sorter);
 			stats.startRun(context);
 		} else {
 			stats= null;
 		}
 		return stats;
 	}

 	private Status createExceptionStatus(InvalidRegistryObjectException x) {
 		// extension has become invalid - log & disable
 		String disable= createBlameMessage();
 		String reason= JavaTextMessages.CompletionProposalComputerDescriptor_reason_invalid;
 		return new Status(IStatus.INFO, JavaPlugin.getPluginId(), IStatus.OK, disable + " " + reason, x); //$NON-NLS-1$
 	}

 	private Status createExceptionStatus(CoreException x) {
 		// unable to instantiate the extension - log & disable
 		String disable= createBlameMessage();
 		String reason= JavaTextMessages.CompletionProposalComputerDescriptor_reason_instantiation;
 		return new Status(IStatus.ERROR, JavaPlugin.getPluginId(), IStatus.OK, disable + " " + reason, x); //$NON-NLS-1$
 	}

 	private Status createExceptionStatus(RuntimeException x) {
 		// misbehaving extension - log & disable
 		String disable= createBlameMessage();
 		String reason= JavaTextMessages.CompletionProposalComputerDescriptor_reason_runtime_ex;
 		return new Status(IStatus.WARNING, JavaPlugin.getPluginId(), IStatus.OK, disable + " " + reason, x); //$NON-NLS-1$
 	}

 	private Status createAPIViolationStatus(String operation) {
 		String disable= createBlameMessage();
 		Object[] args= {operation};
 		String reason= Messages.format(JavaTextMessages.CompletionProposalComputerDescriptor_reason_API, args);
 		return new Status(IStatus.WARNING, JavaPlugin.getPluginId(), IStatus.OK, disable + " " + reason, null); //$NON-NLS-1$
 	}

 	private Status createPerformanceStatus(String operation) {
 		String disable= createBlameMessage();
 		Object[] args= {operation};
 		String reason= Messages.format(JavaTextMessages.CompletionProposalComputerDescriptor_reason_performance, args);
 		return new Status(IStatus.WARNING, JavaPlugin.getPluginId(), IStatus.OK, disable + " " + reason, null); //$NON-NLS-1$
 	}

 	private String createBlameMessage() {
 		Object[] args= { getName(), getId() };
 		String disable= Messages.format(JavaTextMessages.ProposalSorterHandle_blame, args);
 		return disable;
 	}

 	/**
 	 * Returns the error message from the described extension, <code>null</code> for no error.
 	 *
 	 * @return the error message from the described extension, <code>null</code> for no error
 	 */
 	public String getErrorMessage() {
 		return null;
 	}

 }
	/*******************************************************************************
	* 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 org.eclipse.jdt.internal.ui.text.java;

	import java.util.Collections;
	import java.util.List;

	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.IConfigurationElement;
	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.InvalidRegistryObjectException;
	import org.eclipse.core.runtime.PerformanceStats;
	import org.eclipse.core.runtime.Platform;
	import org.eclipse.core.runtime.Status;

	import org.eclipse.jface.text.Assert;

	import org.eclipse.jdt.internal.corext.util.Messages;

	import org.eclipse.jdt.ui.text.java.AbstractProposalSorter;
	import org.eclipse.jdt.ui.text.java.ContentAssistInvocationContext;

	import org.eclipse.jdt.internal.ui.JavaPlugin;

	import org.osgi.framework.Bundle;

	/**
	* The description of an extension to the
	* <code>org.eclipse.jdt.ui.javaCompletionProposalSorters</code> extension point. Instances are
	* immutable.
	*
	* @since 3.2
	*/
	public final class ProposalSorterHandle {
	/** The extension schema name of the id attribute. */
	private static final String ID= "id"; //$NON-NLS-1$
	/** The extension schema name of the name attribute. */
	private static final String NAME= "name"; //$NON-NLS-1$
	/** The extension schema name of the class attribute. */
	private static final String CLASS= "class"; //$NON-NLS-1$
	/** The extension schema name of the activate attribute. */
	private static final String ACTIVATE= "activate"; //$NON-NLS-1$
	/** The name of the performance event used to trace extensions. */
	private static final String PERFORMANCE_EVENT= JavaPlugin.getPluginId() + "/perf/content_assist_sorters/extensions"; //$NON-NLS-1$
	/**
	* If <code>true</code>, execution time of extensions is measured and extensions may be
	* disabled if execution takes too long.
	*/
	private static final boolean MEASURE_PERFORMANCE= PerformanceStats.isEnabled(PERFORMANCE_EVENT);
	/** The one and only operation name. */
	private static final String SORT= "sort"; //$NON-NLS-1$

	/** The identifier of the extension. */
	private final String fId;
	/** The name of the extension. */
	private final String fName;
	/** The class name of the provided <code>AbstractProposalSorter</code>. */
	private final String fClass;
	/** The activate attribute value. */
	private final boolean fActivate;
	/** The configuration element of this extension. */
	private final IConfigurationElement fElement;
	/** The computer, if instantiated, <code>null</code> otherwise. */
	private AbstractProposalSorter fSorter;

	/**
	* Creates a new descriptor.
	*
	* @param element the configuration element to read
	* @throws InvalidRegistryObjectException if the configuration element is not valid any longer
	* or does not contain mandatory attributes
	*/
	ProposalSorterHandle(IConfigurationElement element) throws InvalidRegistryObjectException {
	Assert.isLegal(element != null);

	fElement= element;
	fId= element.getAttribute(ID);
	checkNotNull(fId, ID);

	String name= element.getAttribute(NAME);
	if (name == null)
	fName= fId;
	else
	fName= name;

	String activateAttribute= element.getAttribute(ACTIVATE);
	fActivate= Boolean.valueOf(activateAttribute).booleanValue();

	fClass= element.getAttribute(CLASS);
	checkNotNull(fClass, CLASS);
	}

	/**
	* 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 a cached instance of the sorter as described in the extension's xml. The sorter is
	* {@link #createSorter() created} the first time that this method is called and then cached.
	*
	* @return a new instance of the proposal sorter as described by this descriptor
	* @throws CoreException if the creation fails
	* @throws InvalidRegistryObjectException if the extension is not valid any longer (e.g. due to
	* plug-in unloading)
	*/
	private synchronized AbstractProposalSorter getSorter() throws CoreException, InvalidRegistryObjectException {
	if (fSorter == null && (fActivate \|\| isPluginLoaded()))
	fSorter= createSorter();
	return fSorter;
	}

	private boolean isPluginLoaded() throws InvalidRegistryObjectException {
	Bundle bundle= getBundle();
	return bundle != null && bundle.getState() == Bundle.ACTIVE;
	}

	private Bundle getBundle() throws InvalidRegistryObjectException {
	String symbolicName= fElement.getContributor().getName();
	Bundle bundle= Platform.getBundle(symbolicName);
	return bundle;
	}

	/**
	* Returns a new instance of the sorter as described in the
	* extension's xml.
	*
	* @return a new instance of the completion proposal computer as
	* described by this descriptor
	* @throws CoreException if the creation fails
	* @throws InvalidRegistryObjectException if the extension is not
	* valid any longer (e.g. due to plug-in unloading)
	*/
	private AbstractProposalSorter createSorter() throws CoreException, InvalidRegistryObjectException {
	return (AbstractProposalSorter) fElement.createExecutableExtension(CLASS);
	}

	/**
	* Safely computes completion proposals through the described extension. If the extension throws
	* an exception or otherwise does not adhere to the contract described in
	* {@link AbstractProposalSorter}, the list is returned as is.
	*
	* @param context the invocation context passed on to the extension
	* @param proposals the list of computed completion proposals to be sorted (element type:
	* {@link org.eclipse.jface.text.contentassist.ICompletionProposal}), must be writable
	*/
	public void sortProposals(ContentAssistInvocationContext context, List proposals) {
	IStatus status;
	try {
	AbstractProposalSorter sorter= getSorter();

	PerformanceStats stats= startMeter(SORT, sorter);

	sorter.beginSorting(context);
	Collections.sort(proposals, sorter);
	sorter.endSorting();

	status= stopMeter(stats, SORT);

	// valid result
	if (status == null)
	return;

	status= createAPIViolationStatus(SORT);

	} catch (InvalidRegistryObjectException x) {
	status= createExceptionStatus(x);
	} catch (CoreException x) {
	status= createExceptionStatus(x);
	} catch (RuntimeException x) {
	status= createExceptionStatus(x);
	}

	JavaPlugin.log(status);
	return;
	}

	private IStatus stopMeter(final PerformanceStats stats, String operation) {
	if (MEASURE_PERFORMANCE) {
	stats.endRun();
	if (stats.isFailure())
	return createPerformanceStatus(operation);
	}
	return null;
	}

	private PerformanceStats startMeter(String context, AbstractProposalSorter sorter) {
	final PerformanceStats stats;
	if (MEASURE_PERFORMANCE) {
	stats= PerformanceStats.getStats(PERFORMANCE_EVENT, sorter);
	stats.startRun(context);
	} else {
	stats= null;
	}
	return stats;
	}

	private Status createExceptionStatus(InvalidRegistryObjectException x) {
	// extension has become invalid - log & disable
	String disable= createBlameMessage();
	String reason= JavaTextMessages.CompletionProposalComputerDescriptor_reason_invalid;
	return new Status(IStatus.INFO, JavaPlugin.getPluginId(), IStatus.OK, disable + " " + reason, x); //$NON-NLS-1$
	}

	private Status createExceptionStatus(CoreException x) {
	// unable to instantiate the extension - log & disable
	String disable= createBlameMessage();
	String reason= JavaTextMessages.CompletionProposalComputerDescriptor_reason_instantiation;
	return new Status(IStatus.ERROR, JavaPlugin.getPluginId(), IStatus.OK, disable + " " + reason, x); //$NON-NLS-1$
	}

	private Status createExceptionStatus(RuntimeException x) {
	// misbehaving extension - log & disable
	String disable= createBlameMessage();
	String reason= JavaTextMessages.CompletionProposalComputerDescriptor_reason_runtime_ex;
	return new Status(IStatus.WARNING, JavaPlugin.getPluginId(), IStatus.OK, disable + " " + reason, x); //$NON-NLS-1$
	}

	private Status createAPIViolationStatus(String operation) {
	String disable= createBlameMessage();
	Object[] args= {operation};
	String reason= Messages.format(JavaTextMessages.CompletionProposalComputerDescriptor_reason_API, args);
	return new Status(IStatus.WARNING, JavaPlugin.getPluginId(), IStatus.OK, disable + " " + reason, null); //$NON-NLS-1$
	}

	private Status createPerformanceStatus(String operation) {
	String disable= createBlameMessage();
	Object[] args= {operation};
	String reason= Messages.format(JavaTextMessages.CompletionProposalComputerDescriptor_reason_performance, args);
	return new Status(IStatus.WARNING, JavaPlugin.getPluginId(), IStatus.OK, disable + " " + reason, null); //$NON-NLS-1$
	}

	private String createBlameMessage() {
	Object[] args= { getName(), getId() };
	String disable= Messages.format(JavaTextMessages.ProposalSorterHandle_blame, args);
	return disable;
	}

	/**
	* Returns the error message from the described extension, <code>null</code> for no error.
	*
	* @return the error message from the described extension, <code>null</code> for no error
	*/
	public String getErrorMessage() {
	return null;
	}

	}