| /******************************************************************************* |
| * Copyright (c) 2000, 2008 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.core.expressions; |
| |
| import org.osgi.framework.Bundle; |
| |
| import org.eclipse.core.internal.expressions.PropertyTesterDescriptor; |
| |
| import org.eclipse.core.runtime.IConfigurationElement; |
| import org.eclipse.core.runtime.Platform; |
| |
| /** |
| * Abstract superclass of all property testers. Implementation classes of |
| * the extension point <code>org.eclipse.core.expresssions.propertyTesters |
| * </code> must extend <code>PropertyTester</code>. |
| * <p> |
| * A property tester implements the property tests enumerated in the property |
| * tester extension point. For the following property test extension |
| * <pre> |
| * <propertyTester |
| * namespace="org.eclipse.jdt.core" |
| * id="org.eclipse.jdt.core.IPackageFragmentTester" |
| * properties="isDefaultPackage" |
| * type="org.eclipse.jdt.core.IPackageFragment" |
| * class="org.eclipse.demo.MyPackageFragmentTester"> |
| * </propertyTester> |
| * </pre> |
| * the corresponding implementation class looks like: |
| * <pre> |
| * public class MyPackageFragmentTester { |
| * public boolean test(Object receiver, String property, Object[] args, Object expectedValue) { |
| * IPackageFragment fragement= (IPackageFragment)receiver; |
| * if ("isDefaultPackage".equals(property)) { |
| * return expectedValue == null |
| * ? fragement.isDefaultPackage() |
| * : fragement.isDefaultPackage() == ((Boolean)expectedValue).booleanValue(); |
| * } |
| * Assert.isTrue(false); |
| * return false; |
| * } |
| * } |
| * </pre> |
| * The property can then be used in a test expression as follows: |
| * <pre> |
| * <instanceof value="org.eclipse.core.IPackageFragment"/> |
| * <test property="org.eclipse.jdt.core.isDefaultPackage"/> |
| * </pre> |
| * </p> |
| * <p> |
| * There is no guarantee that the same instance of a property tester is used |
| * to handle <test property="..."/> requests. So property testers |
| * should always be implemented in a stateless fashion. |
| * </p> |
| * @since 3.0 |
| */ |
| public abstract class PropertyTester implements IPropertyTester { |
| |
| private IConfigurationElement fConfigElement; |
| private String fNamespace; |
| private String fProperties; |
| |
| /** |
| * Initialize the property tester with the given name space and property. |
| * <p> |
| * Note: this method is for internal use only. Clients must not call |
| * this method. |
| * </p> |
| * @param descriptor the descriptor object for this tester |
| * |
| * @noreference This method is not intended to be referenced by clients. |
| */ |
| public final void internalInitialize(PropertyTesterDescriptor descriptor) { |
| fProperties= descriptor.getProperties(); |
| fNamespace= descriptor.getNamespace(); |
| fConfigElement= descriptor.getConfigurationElement(); |
| } |
| |
| /** |
| * Note: this method is for internal use only. Clients must not call |
| * this method. |
| * |
| * @return the property tester descriptor |
| * |
| * @noreference This method is not intended to be referenced by clients. |
| */ |
| public final PropertyTesterDescriptor internalCreateDescriptor() { |
| return new PropertyTesterDescriptor(fConfigElement, fNamespace, fProperties); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public final boolean handles(String namespace, String property) { |
| return fNamespace.equals(namespace) && fProperties.indexOf("," + property + ",") != -1; //$NON-NLS-1$//$NON-NLS-2$ |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public final boolean isInstantiated() { |
| return true; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean isDeclaringPluginActive() { |
| Bundle bundle= Platform.getBundle(fConfigElement.getContributor().getName()); |
| return bundle.getState() == Bundle.ACTIVE; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public final IPropertyTester instantiate() { |
| return this; |
| } |
| } |