package org.apache.maven.index.util;
/*
* 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.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.apache.maven.index.context.IndexCreator;
import org.codehaus.plexus.util.dag.CycleDetectedException;
import org.codehaus.plexus.util.dag.DAG;
import org.codehaus.plexus.util.dag.TopologicalSorter;
public class IndexCreatorSorter
{
public static List<IndexCreator> sort( List<? extends IndexCreator> creators )
throws IllegalArgumentException
{
try
{
final HashMap<String, IndexCreator> creatorsById = new HashMap<String, IndexCreator>( creators.size() );
DAG dag = new DAG();
for ( IndexCreator creator : creators )
{
creatorsById.put( creator.getId(), creator );
dag.addVertex( creator.getId() );
for ( String depId : creator.getCreatorDependencies() )
{
dag.addEdge( creator.getId(), depId );
}
}
List<String> sortedIds = TopologicalSorter.sort( dag );
final ArrayList<IndexCreator> sortedCreators = new ArrayList<IndexCreator>( creators.size() );
for ( String id : sortedIds )
{
final IndexCreator creator = creatorsById.get( id );
if ( creator != null )
{
sortedCreators.add( creator );
}
else
{
throw new IllegalArgumentException( String.format(
"IndexCreator with ID=\"%s\" does not exists, the present creator ID=\"%s\" depends on it!",
id, dag.getParentLabels( id ) ) );
}
}
return sortedCreators;
}
catch ( CycleDetectedException e )
{
throw new IllegalArgumentException( "Supplied IndexCreator inter-dependencies", e );
}
}
}