diff options
Diffstat (limited to 'plugins/org.eclipse.eef.ide/src/org/eclipse/eef/ide/internal/extensions/impl/DescriptorRegistryEventListener.java')
| -rw-r--r-- | plugins/org.eclipse.eef.ide/src/org/eclipse/eef/ide/internal/extensions/impl/DescriptorRegistryEventListener.java | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/plugins/org.eclipse.eef.ide/src/org/eclipse/eef/ide/internal/extensions/impl/DescriptorRegistryEventListener.java b/plugins/org.eclipse.eef.ide/src/org/eclipse/eef/ide/internal/extensions/impl/DescriptorRegistryEventListener.java new file mode 100644 index 000000000..21393cc46 --- /dev/null +++ b/plugins/org.eclipse.eef.ide/src/org/eclipse/eef/ide/internal/extensions/impl/DescriptorRegistryEventListener.java @@ -0,0 +1,161 @@ +/******************************************************************************* + * Copyright (c) 2015 Obeo. + * 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: + * Obeo - initial API and implementation + *******************************************************************************/ +package org.eclipse.eef.ide.internal.extensions.impl; + +import java.text.MessageFormat; + +import org.eclipse.core.runtime.CoreException; +import org.eclipse.core.runtime.IConfigurationElement; +import org.eclipse.eef.ide.internal.EEFIdePlugin; +import org.eclipse.eef.ide.internal.Messages; +import org.eclipse.eef.ide.internal.extensions.AbstractRegistryEventListener; +import org.eclipse.eef.ide.internal.extensions.IItemDescriptor; +import org.eclipse.eef.ide.internal.extensions.IItemRegistry; + +/** + * Utility class used to retrieved the descriptors of extensions. + * + * @author adaussy + * @author sbegaudeau + * + * @param <T> + * The type of the Object described + */ +public class DescriptorRegistryEventListener<T> extends AbstractRegistryEventListener { + /** Id attribute of the extension point. */ + public static final String ID_DESCRIPTOR_ATTR = "id"; //$NON-NLS-1$ + + /** Label attribute of extension point. */ + public static final String LABEL_DESCRIPTOR_ATTR = "label"; //$NON-NLS-1$ + + /** Description attribute of extension point. */ + public static final String DESCRIPTION_DESCRIPTOR_ATTR = "description"; //$NON-NLS-1$ + + /** Implementation class attribute of extension point. */ + public static final String IMPL_CLASS_DESCRIPTOR_ATTR = "class"; //$NON-NLS-1$ + + /** Descriptor tag of extension point. */ + public static final String TAG_DESCRIPTOR = "descriptor"; //$NON-NLS-1$ + + /** + * The item registry. + */ + private IItemRegistry<T> itemRegistry; + + /** + * The constructor. + * + * @param namespace + * The namespace of the extension point + * @param extensionPointID + * The identifier of the extension point + * @param itemRegistry + * The {@link IItemRegistry} + */ + public DescriptorRegistryEventListener(String namespace, String extensionPointID, IItemRegistry<T> itemRegistry) { + super(namespace, extensionPointID); + this.itemRegistry = itemRegistry; + } + + /** + * {@inheritDoc} + * + * @see org.eclipse.eef.ide.internal.extensions.AbstractRegistryEventListener#validateConfigurationElement(org.eclipse.core.runtime.IConfigurationElement) + */ + @Override + protected boolean validateConfigurationElement(IConfigurationElement configurationElement) { + boolean isValid = false; + + if (TAG_DESCRIPTOR.equals(configurationElement.getName())) { + if (!this.isValidAttribute(configurationElement, ID_DESCRIPTOR_ATTR)) { + String message = MessageFormat.format(Messages.DescriptorRegistryEventListener_missingAttribute, + configurationElement.getNamespaceIdentifier(), ID_DESCRIPTOR_ATTR); + EEFIdePlugin.getImplementation().logError(message, null); + } else if (!this.isValidAttribute(configurationElement, LABEL_DESCRIPTOR_ATTR)) { + String message = MessageFormat.format(Messages.DescriptorRegistryEventListener_missingAttribute, + configurationElement.getNamespaceIdentifier(), LABEL_DESCRIPTOR_ATTR); + EEFIdePlugin.getImplementation().logError(message, null); + } else if (!this.isValidAttribute(configurationElement, DESCRIPTION_DESCRIPTOR_ATTR)) { + String message = MessageFormat.format(Messages.DescriptorRegistryEventListener_missingAttribute, + configurationElement.getNamespaceIdentifier(), DESCRIPTION_DESCRIPTOR_ATTR); + EEFIdePlugin.getImplementation().logError(message, null); + } else if (!this.isValidAttribute(configurationElement, IMPL_CLASS_DESCRIPTOR_ATTR)) { + String message = MessageFormat.format(Messages.DescriptorRegistryEventListener_missingAttribute, + configurationElement.getNamespaceIdentifier(), IMPL_CLASS_DESCRIPTOR_ATTR); + EEFIdePlugin.getImplementation().logError(message, null); + } else { + isValid = true; + } + } + + return isValid; + } + + /** + * Indicates if an attribute of the configuration element is valid. + * + * @param configurationElement + * The configuration element + * @param attributeName + * The attribute name + * @return <code>true</code> if the attribute is valid, <code>false</code> + * otherwise + */ + private boolean isValidAttribute(IConfigurationElement configurationElement, String attributeName) { + return configurationElement.getAttribute(attributeName) != null + && !"".equals(configurationElement.getAttribute(attributeName)); //$NON-NLS-1$ + } + + /** + * {@inheritDoc} + * + * @see org.eclipse.eef.ide.internal.extensions.AbstractRegistryEventListener#processAddition(org.eclipse.core.runtime.IConfigurationElement) + */ + @SuppressWarnings("unchecked") + @Override + protected boolean processAddition(IConfigurationElement configurationElement) { + String id = configurationElement.getAttribute(ID_DESCRIPTOR_ATTR); + String label = configurationElement.getAttribute(LABEL_DESCRIPTOR_ATTR); + String description = configurationElement.getAttribute(DESCRIPTION_DESCRIPTOR_ATTR); + + try { + T instance = (T) configurationElement.createExecutableExtension(IMPL_CLASS_DESCRIPTOR_ATTR); + + ItemDescriptor<T> descriptor = new ItemDescriptor<T>(id, label, description, instance); + IItemDescriptor<T> previous = this.itemRegistry.add(descriptor); + if (previous != null) { + String message = MessageFormat.format( + Messages.DescriptorRegistryEventListener_extensionAlreadyContributed, + configurationElement.getAttribute(ID_DESCRIPTOR_ATTR)); + EEFIdePlugin.getImplementation().logWarning(message, null); + } + } catch (CoreException e) { + String message = MessageFormat.format(Messages.DescriptorRegistryEventListener_cannotInstantiateExtension, + configurationElement.getAttribute(IMPL_CLASS_DESCRIPTOR_ATTR)); + EEFIdePlugin.getImplementation().logError(message, e); + + return false; + } + + return true; + } + + /** + * {@inheritDoc} + * + * @see org.eclipse.eef.ide.internal.extensions.AbstractRegistryEventListener#processRemoval(org.eclipse.core.runtime.IConfigurationElement) + */ + @Override + protected boolean processRemoval(IConfigurationElement configurationElement) { + return this.itemRegistry.remove(configurationElement.getAttribute(ID_DESCRIPTOR_ATTR)) != null; + } + +} |