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;
023import static java.util.Objects.requireNonNull;
024
025import org.eclipse.aether.graph.DependencyFilter;
026import org.eclipse.aether.graph.DependencyNode;
027
028/**
029 * A dependency filter that negates another filter.
030 */
031public final class NotDependencyFilter
032    implements DependencyFilter
033{
034
035    private final DependencyFilter filter;
036
037    /**
038     * Creates a new filter negatint the specified filter.
039     *
040     * @param filter The filter to negate, must not be {@code null}.
041     */
042    public NotDependencyFilter( DependencyFilter filter )
043    {
044        this.filter = requireNonNull( filter, "dependency filter cannot be null" );
045    }
046
047    public boolean accept( DependencyNode node, List<DependencyNode> parents )
048    {
049        return !filter.accept( node, parents );
050    }
051
052    @Override
053    public boolean equals( Object obj )
054    {
055        if ( this == obj )
056        {
057            return true;
058        }
059
060        if ( obj == null || !getClass().equals( obj.getClass() ) )
061        {
062            return false;
063        }
064
065        NotDependencyFilter that = (NotDependencyFilter) obj;
066
067        return this.filter.equals( that.filter );
068    }
069
070    @Override
071    public int hashCode()
072    {
073        int hash = getClass().hashCode();
074        hash = hash * 31 + filter.hashCode();
075        return hash;
076    }
077
078}