| package org.eclipse.aether.util.repository; |
| |
| /* |
| * 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. |
| */ |
| |
| import java.io.File; |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.LinkedHashSet; |
| import java.util.List; |
| |
| import org.eclipse.aether.artifact.Artifact; |
| import org.eclipse.aether.repository.WorkspaceReader; |
| import org.eclipse.aether.repository.WorkspaceRepository; |
| |
| /** |
| * A workspace reader that delegates to a chain of other readers, effectively aggregating their contents. |
| */ |
| public final class ChainedWorkspaceReader |
| implements WorkspaceReader |
| { |
| |
| private List<WorkspaceReader> readers = new ArrayList<WorkspaceReader>(); |
| |
| private WorkspaceRepository repository; |
| |
| /** |
| * Creates a new workspace reader by chaining the specified readers. |
| * |
| * @param readers The readers to chain, may be {@code null}. |
| * @see #newInstance(WorkspaceReader, WorkspaceReader) |
| */ |
| public ChainedWorkspaceReader( WorkspaceReader... readers ) |
| { |
| if ( readers != null ) |
| { |
| Collections.addAll( this.readers, readers ); |
| } |
| |
| StringBuilder buffer = new StringBuilder(); |
| for ( WorkspaceReader reader : this.readers ) |
| { |
| if ( buffer.length() > 0 ) |
| { |
| buffer.append( '+' ); |
| } |
| buffer.append( reader.getRepository().getContentType() ); |
| } |
| |
| repository = new WorkspaceRepository( buffer.toString(), new Key( this.readers ) ); |
| } |
| |
| /** |
| * Creates a new workspace reader by chaining the specified readers. In contrast to the constructor, this factory |
| * method will avoid creating an actual chained reader if one of the specified readers is actually {@code null}. |
| * |
| * @param reader1 The first workspace reader, may be {@code null}. |
| * @param reader2 The second workspace reader, may be {@code null}. |
| * @return The chained reader or {@code null} if no workspace reader was supplied. |
| */ |
| public static WorkspaceReader newInstance( WorkspaceReader reader1, WorkspaceReader reader2 ) |
| { |
| if ( reader1 == null ) |
| { |
| return reader2; |
| } |
| else if ( reader2 == null ) |
| { |
| return reader1; |
| } |
| return new ChainedWorkspaceReader( reader1, reader2 ); |
| } |
| |
| public File findArtifact( Artifact artifact ) |
| { |
| File file = null; |
| |
| for ( WorkspaceReader reader : readers ) |
| { |
| file = reader.findArtifact( artifact ); |
| if ( file != null ) |
| { |
| break; |
| } |
| } |
| |
| return file; |
| } |
| |
| public List<String> findVersions( Artifact artifact ) |
| { |
| Collection<String> versions = new LinkedHashSet<String>(); |
| |
| for ( WorkspaceReader reader : readers ) |
| { |
| versions.addAll( reader.findVersions( artifact ) ); |
| } |
| |
| return Collections.unmodifiableList( new ArrayList<String>( versions ) ); |
| } |
| |
| public WorkspaceRepository getRepository() |
| { |
| Key key = new Key( readers ); |
| if ( !key.equals( repository.getKey() ) ) |
| { |
| repository = new WorkspaceRepository( repository.getContentType(), key ); |
| } |
| return repository; |
| } |
| |
| private static class Key |
| { |
| |
| private final List<Object> keys = new ArrayList<Object>(); |
| |
| public Key( List<WorkspaceReader> readers ) |
| { |
| for ( WorkspaceReader reader : readers ) |
| { |
| keys.add( reader.getRepository().getKey() ); |
| } |
| } |
| |
| @Override |
| public boolean equals( Object obj ) |
| { |
| if ( this == obj ) |
| { |
| return true; |
| } |
| if ( obj == null || !getClass().equals( obj.getClass() ) ) |
| { |
| return false; |
| } |
| return keys.equals( ( (Key) obj ).keys ); |
| } |
| |
| @Override |
| public int hashCode() |
| { |
| return keys.hashCode(); |
| } |
| |
| } |
| |
| } |