| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 org.apache.jackrabbit.oak.spi.commit; |
| |
| import static com.google.common.base.Preconditions.checkNotNull; |
| import static java.util.Arrays.asList; |
| |
| import java.util.Collection; |
| import java.util.List; |
| |
| import org.apache.jackrabbit.oak.api.CommitFailedException; |
| import org.apache.jackrabbit.oak.spi.state.NodeBuilder; |
| import org.apache.jackrabbit.oak.spi.state.NodeState; |
| import org.jetbrains.annotations.NotNull; |
| import org.jetbrains.annotations.Nullable; |
| |
| import com.google.common.collect.Lists; |
| |
| /** |
| * Aggregation of a list of editor providers into a single provider. |
| */ |
| public class CompositeEditorProvider implements EditorProvider { |
| |
| private static final EditorProvider EMPTY_PROVIDER = |
| new EditorProvider() { |
| @Override @Nullable |
| public Editor getRootEditor( |
| NodeState before, NodeState after, |
| NodeBuilder builder, CommitInfo info) { |
| return null; |
| } |
| }; |
| |
| @NotNull |
| public static EditorProvider compose( |
| @NotNull Collection<? extends EditorProvider> providers) { |
| checkNotNull(providers); |
| switch (providers.size()) { |
| case 0: |
| return EMPTY_PROVIDER; |
| case 1: |
| return providers.iterator().next(); |
| default: |
| return new CompositeEditorProvider(providers); |
| } |
| } |
| |
| private final Collection<? extends EditorProvider> providers; |
| |
| private CompositeEditorProvider( |
| Collection<? extends EditorProvider> providers) { |
| this.providers = providers; |
| } |
| |
| public CompositeEditorProvider(EditorProvider... providers) { |
| this(asList(providers)); |
| } |
| |
| @Override @Nullable |
| public Editor getRootEditor( |
| NodeState before, NodeState after, NodeBuilder builder, |
| CommitInfo info) throws CommitFailedException { |
| List<Editor> list = Lists.newArrayListWithCapacity(providers.size()); |
| for (EditorProvider provider : providers) { |
| Editor editor = provider.getRootEditor(before, after, builder, info); |
| if (editor != null) { |
| list.add(editor); |
| } |
| } |
| return CompositeEditor.compose(list); |
| } |
| |
| @Override |
| public String toString() { |
| return "CompositeEditorProvider : (" + providers.toString() + ")"; |
| } |
| } |