package org.apache.maven.plugin.dependency.treeSerializers ;
/*
* 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.Writer;
import java.util.ArrayList;
import java.util.List;
import org.apache.maven.shared.dependency.graph.DependencyNode;
import org.apache.maven.shared.dependency.graph.traversal.DependencyNodeVisitor;
/**
* A dependency node visitor that serializes visited nodes to a writer using the TGF format.
*
* http://en.wikipedia.org/wiki/Trivial_Graph_Format
*
* @author <a href="mailto:jerome.creignou@gmail.com">Jerome Creignou</a>
* @since 2.1
*/
public class TGFDependencyNodeVisitor
extends AbstractSerializingVisitor
implements DependencyNodeVisitor
{
/**
* Utiity class to write an Edge.
*
* @author <a href="mailto:jerome.creignou@gmail.com">Jerome Creignou</a>
*/
static final class EdgeAppender
{
/**
* Edge start.
*/
private DependencyNode from;
/**
* Edge end.
*/
private DependencyNode to;
/**
* Edge label. (optional)
*/
private String label;
/**
* Build a new EdgeAppender.
*
* @param from edge start.
* @param to edge end
* @param label optional label.
*/
public EdgeAppender( DependencyNode from, DependencyNode to, String label )
{
super();
this.from = from;
this.to = to;
this.label = label;
}
/**
* build a string representing the edge.
*/
public String toString()
{
StringBuilder result = new StringBuilder( generateId( from ) );
result.append( ' ' ).append( generateId( to ) );
if ( label != null )
{
result.append( ' ' ).append( label );
}
return result.toString();
}
}
/**
* List of edges.
*/
private List<EdgeAppender> edges = new ArrayList<EdgeAppender>();
/**
* Constructor.
*
* @param writer the writer to write to.
*/
public TGFDependencyNodeVisitor( Writer writer )
{
super( writer );
}
/**
* {@inheritDoc}
*/
public boolean endVisit( DependencyNode node )
{
if ( node.getParent() == null || node.getParent() == node )
{
// dump edges on last node endVisit
writer.println( "#" );
for ( EdgeAppender edge : edges )
{
writer.println( edge.toString() );
}
}
else
{
DependencyNode p = node.getParent();
// using scope as edge label.
edges.add( new EdgeAppender( p, node, node.getArtifact().getScope() ) );
}
return true;
}
/**
* {@inheritDoc}
*/
public boolean visit( DependencyNode node )
{
// write node
writer.write( generateId( node ) );
writer.write( " " );
writer.println( node.toNodeString() );
return true;
}
/**
* Generate a unique id from a DependencyNode.
* <p>
* Current implementation is rather simple and uses hashcode.
* </p>
*
* @param node the DependencyNode to use.
* @return the unique id.
*/
private static String generateId( DependencyNode node )
{
return String.valueOf( node.hashCode() );
}
}