001package org.eclipse.aether.util.filter;
002
003/*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements.  See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership.  The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License.  You may obtain a copy of the License at
011 * 
012 *  http://www.apache.org/licenses/LICENSE-2.0
013 * 
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied.  See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022import java.util.List;
023
024import org.eclipse.aether.graph.DependencyFilter;
025import org.eclipse.aether.graph.DependencyNode;
026
027/**
028 * A dependency filter that negates another filter.
029 */
030public final class NotDependencyFilter
031    implements DependencyFilter
032{
033
034    private final DependencyFilter filter;
035
036    /**
037     * Creates a new filter negatint the specified filter.
038     * 
039     * @param filter The filter to negate, must not be {@code null}.
040     */
041    public NotDependencyFilter( DependencyFilter filter )
042    {
043        if ( filter == null )
044        {
045            throw new IllegalArgumentException( "no filter specified" );
046        }
047        this.filter = filter;
048    }
049
050    public boolean accept( DependencyNode node, List<DependencyNode> parents )
051    {
052        return !filter.accept( node, parents );
053    }
054
055    @Override
056    public boolean equals( Object obj )
057    {
058        if ( this == obj )
059        {
060            return true;
061        }
062
063        if ( obj == null || !getClass().equals( obj.getClass() ) )
064        {
065            return false;
066        }
067
068        NotDependencyFilter that = (NotDependencyFilter) obj;
069
070        return this.filter.equals( that.filter );
071    }
072
073    @Override
074    public int hashCode()
075    {
076        int hash = getClass().hashCode();
077        hash = hash * 31 + filter.hashCode();
078        return hash;
079    }
080
081}