package org.apache.maven.continuum.utils;
/*
* 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 org.apache.maven.continuum.model.project.Project;
import org.apache.maven.continuum.model.project.ProjectDependency;
import org.codehaus.plexus.logging.Logger;
import org.codehaus.plexus.util.dag.CycleDetectedException;
import org.codehaus.plexus.util.dag.DAG;
import org.codehaus.plexus.util.dag.TopologicalSorter;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* Sort projects by dependencies.
*
* @author <a href="mailto:brett@apache.org">Brett Porter</a>
* @version $Id: ProjectSorter.java 584884 2007-10-15 20:06:16Z evenisse $
*/
public class ProjectSorter
{
private ProjectSorter()
{
// no touchy...
}
/**
* Sort a list of projects.
* <ul>
* <li>collect all the vertices for the projects that we want to build.</li>
* <li>iterate through the deps of each project and if that dep is within
* the set of projects we want to build then add an edge, otherwise throw
* the edge away because that dependency is not within the set of projects
* we are trying to build. we assume a closed set.</li>
* <li>do a topo sort on the graph that remains.</li>
* </ul>
*/
public static List<Project> getSortedProjects( Collection<Project> projects, Logger logger )
throws CycleDetectedException
{
DAG dag = new DAG();
Map<String, Project> projectMap = new HashMap<String, Project>();
for ( Project project : projects )
{
String id = getProjectId( project );
if ( dag.getVertex( id ) != null )
{
logger.warn( "Project '" + id + "' is duplicated in the reactor" );
}
dag.addVertex( id );
projectMap.put( id, project );
}
for ( Project project : projects )
{
String id = getProjectId( project );
// Dependencies
for ( Object o : project.getDependencies() )
{
ProjectDependency dependency = (ProjectDependency) o;
String dependencyId = getDependencyId( dependency );
if ( dag.getVertex( dependencyId ) != null )
{
dag.addEdge( id, dependencyId );
}
}
// Parent
ProjectDependency parent = project.getParent();
if ( parent != null )
{
String parentId = getDependencyId( parent );
if ( dag.getVertex( parentId ) != null )
{
// Parent is added as an edge, but must not cause a cycle - so we remove any other edges it has in conflict
if ( dag.hasEdge( parentId, id ) )
{
dag.removeEdge( parentId, id );
}
dag.addEdge( id, parentId );
}
}
}
List<Project> sortedProjects = new ArrayList<Project>();
for ( Object o : TopologicalSorter.sort( dag ) )
{
String id = (String) o;
sortedProjects.add( projectMap.get( id ) );
}
return sortedProjects;
}
private static String getProjectId( Project project )
{
String groupId;
String artifactId;
if ( project.getGroupId() == null )
{
groupId = project.getName();
}
else
{
groupId = project.getGroupId();
}
if ( project.getArtifactId() == null )
{
artifactId = project.getName();
}
else
{
artifactId = project.getArtifactId();
}
return groupId + ":" + artifactId + ":" + project.getVersion();
}
private static String getDependencyId( ProjectDependency project )
{
return project.getGroupId() + ":" + project.getArtifactId() + ":" + project.getVersion();
}
}