| /* |
| * Copyright 2000-2009 JetBrains s.r.o. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package com.intellij.openapi.extensions; |
| |
| import com.intellij.util.NullableFunction; |
| import com.intellij.util.containers.ContainerUtil; |
| import org.jetbrains.annotations.NotNull; |
| import org.jetbrains.annotations.Nullable; |
| |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.List; |
| |
| /** |
| * @author peter |
| */ |
| public abstract class SmartExtensionPoint<Extension,V> implements ExtensionPointAndAreaListener<Extension> { |
| private final Collection<V> myExplicitExtensions; |
| private ExtensionPoint<Extension> myExtensionPoint; |
| private List<V> myCache; |
| |
| protected SmartExtensionPoint(@NotNull final Collection<V> explicitExtensions) { |
| myExplicitExtensions = explicitExtensions; |
| } |
| |
| @NotNull |
| protected abstract ExtensionPoint<Extension> getExtensionPoint(); |
| |
| public final void addExplicitExtension(@NotNull V extension) { |
| synchronized (myExplicitExtensions) { |
| myExplicitExtensions.add(extension); |
| myCache = null; |
| } |
| } |
| |
| public final void removeExplicitExtension(@NotNull V extension) { |
| synchronized (myExplicitExtensions) { |
| myExplicitExtensions.remove(extension); |
| myCache = null; |
| } |
| } |
| |
| @Nullable |
| protected abstract V getExtension(@NotNull final Extension extension); |
| |
| @NotNull |
| public final List<V> getExtensions() { |
| synchronized (myExplicitExtensions) { |
| if (myCache == null) { |
| myExtensionPoint = getExtensionPoint(); |
| myExtensionPoint.addExtensionPointListener(this); |
| myCache = new ArrayList<V>(myExplicitExtensions); |
| myCache.addAll(ContainerUtil.mapNotNull(myExtensionPoint.getExtensions(), new NullableFunction<Extension, V>() { |
| @Override |
| @Nullable |
| public V fun(final Extension extension) { |
| return getExtension(extension); |
| } |
| })); |
| } |
| return myCache; |
| } |
| } |
| |
| @Override |
| public final void extensionAdded(@NotNull final Extension extension, @Nullable final PluginDescriptor pluginDescriptor) { |
| dropCache(); |
| } |
| |
| public final void dropCache() { |
| synchronized (myExplicitExtensions) { |
| if (myCache != null) { |
| myCache = null; |
| myExtensionPoint.removeExtensionPointListener(this); |
| myExtensionPoint = null; |
| } |
| } |
| } |
| |
| @Override |
| public final void extensionRemoved(@NotNull final Extension extension, @Nullable final PluginDescriptor pluginDescriptor) { |
| dropCache(); |
| } |
| |
| @Override |
| public void areaReplaced(final ExtensionsArea area) { |
| dropCache(); |
| } |
| } |