| package org.eclipse.aether.util.graph.version; |
| |
| /* |
| * 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.Arrays; |
| import java.util.Collection; |
| |
| import org.eclipse.aether.RepositoryException; |
| import org.eclipse.aether.collection.DependencyCollectionContext; |
| import org.eclipse.aether.collection.VersionFilter; |
| |
| /** |
| * A version filter that combines multiple version filters into a chain where each filter gets invoked one after the |
| * other, thereby accumulating their filtering effects. |
| */ |
| public final class ChainedVersionFilter |
| implements VersionFilter |
| { |
| |
| private final VersionFilter[] filters; |
| |
| private int hashCode; |
| |
| /** |
| * Chains the specified version filters. |
| * |
| * @param filter1 The first version filter, may be {@code null}. |
| * @param filter2 The second version filter, may be {@code null}. |
| * @return The chained version filter or {@code null} if both input filters are {@code null}. |
| */ |
| public static VersionFilter newInstance( VersionFilter filter1, VersionFilter filter2 ) |
| { |
| if ( filter1 == null ) |
| { |
| return filter2; |
| } |
| if ( filter2 == null ) |
| { |
| return filter1; |
| } |
| return new ChainedVersionFilter( new VersionFilter[] { filter1, filter2 } ); |
| } |
| |
| /** |
| * Chains the specified version filters. |
| * |
| * @param filters The version filters to chain, must not be {@code null} or contain {@code null}. |
| * @return The chained version filter or {@code null} if the input array is empty. |
| */ |
| public static VersionFilter newInstance( VersionFilter... filters ) |
| { |
| if ( filters.length <= 1 ) |
| { |
| if ( filters.length <= 0 ) |
| { |
| return null; |
| } |
| return filters[0]; |
| } |
| return new ChainedVersionFilter( filters.clone() ); |
| } |
| |
| /** |
| * Chains the specified version filters. |
| * |
| * @param filters The version filters to chain, must not be {@code null} or contain {@code null}. |
| * @return The chained version filter or {@code null} if the input collection is empty. |
| */ |
| public static VersionFilter newInstance( Collection<? extends VersionFilter> filters ) |
| { |
| if ( filters.size() <= 1 ) |
| { |
| if ( filters.isEmpty() ) |
| { |
| return null; |
| } |
| return filters.iterator().next(); |
| } |
| return new ChainedVersionFilter( filters.toArray( new VersionFilter[0] ) ); |
| } |
| |
| private ChainedVersionFilter( VersionFilter[] filters ) |
| { |
| this.filters = filters; |
| } |
| |
| public void filterVersions( VersionFilterContext context ) |
| throws RepositoryException |
| { |
| for ( int i = 0, n = filters.length; i < n && context.getCount() > 0; i++ ) |
| { |
| filters[i].filterVersions( context ); |
| } |
| } |
| |
| public VersionFilter deriveChildFilter( DependencyCollectionContext context ) |
| { |
| VersionFilter[] children = null; |
| int removed = 0; |
| for ( int i = 0, n = filters.length; i < n; i++ ) |
| { |
| VersionFilter child = filters[i].deriveChildFilter( context ); |
| if ( children != null ) |
| { |
| children[i - removed] = child; |
| } |
| else if ( child != filters[i] ) |
| { |
| children = new VersionFilter[filters.length]; |
| System.arraycopy( filters, 0, children, 0, i ); |
| children[i - removed] = child; |
| } |
| if ( child == null ) |
| { |
| removed++; |
| } |
| } |
| if ( children == null ) |
| { |
| return this; |
| } |
| if ( removed > 0 ) |
| { |
| int count = filters.length - removed; |
| if ( count <= 0 ) |
| { |
| return null; |
| } |
| if ( count == 1 ) |
| { |
| return children[0]; |
| } |
| VersionFilter[] tmp = new VersionFilter[count]; |
| System.arraycopy( children, 0, tmp, 0, count ); |
| children = tmp; |
| } |
| return new ChainedVersionFilter( children ); |
| } |
| |
| @Override |
| public boolean equals( Object obj ) |
| { |
| if ( this == obj ) |
| { |
| return true; |
| } |
| else if ( null == obj || !getClass().equals( obj.getClass() ) ) |
| { |
| return false; |
| } |
| |
| ChainedVersionFilter that = (ChainedVersionFilter) obj; |
| return Arrays.equals( filters, that.filters ); |
| } |
| |
| @Override |
| public int hashCode() |
| { |
| if ( hashCode == 0 ) |
| { |
| int hash = getClass().hashCode(); |
| hash = hash * 31 + Arrays.hashCode( filters ); |
| hashCode = hash; |
| } |
| return hashCode; |
| } |
| |
| } |