Java tutorial
/* * Copyright 2016 the original author or authors. * * Licensed 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. */ package org.gradle.api.internal.artifacts.ivyservice.resolveengine.excludes; import com.google.common.collect.Sets; import java.util.Collection; import java.util.Set; abstract class AbstractCompositeExclusion extends AbstractModuleExclusion { private int hashCode = -1; abstract Collection<AbstractModuleExclusion> getFilters(); @Override public String toString() { StringBuilder builder = new StringBuilder(); builder.append("{"); builder.append(getClass().getSimpleName()); for (AbstractModuleExclusion spec : getFilters()) { builder.append(' '); builder.append(spec); } builder.append("}"); return builder.toString(); } @Override protected boolean doExcludesSameModulesAs(AbstractModuleExclusion other) { AbstractCompositeExclusion spec = (AbstractCompositeExclusion) other; Collection<AbstractModuleExclusion> thisFilters = getFilters(); Collection<AbstractModuleExclusion> otherFilters = spec.getFilters(); // To make the comparison faster, we compute the sets of specs that exist in this exclusion, but not in the other // and the set of specs that exist in the other and not in this one. Then we only need to check if the missing // from one set have an equivalent in the missing of the other set, which is much faster than checking all of them Set<AbstractModuleExclusion> miss1 = Sets.newHashSetWithExpectedSize(thisFilters.size()); Set<AbstractModuleExclusion> miss2 = Sets.newHashSetWithExpectedSize(otherFilters.size()); for (AbstractModuleExclusion exclusion : thisFilters) { if (!otherFilters.contains(exclusion)) { miss1.add(exclusion); } } for (AbstractModuleExclusion otherFilter : otherFilters) { if (!thisFilters.contains(otherFilter)) { miss2.add(otherFilter); } } return (miss1.isEmpty() && miss2.isEmpty()) || (implies(miss1, miss2) && implies(miss2, miss1)); } @Override protected boolean doEquals(Object obj) { AbstractCompositeExclusion other = (AbstractCompositeExclusion) obj; return hashCode() == other.hashCode() && getFilters().equals(other.getFilters()); } @Override protected int doHashCode() { if (hashCode != -1) { return hashCode; } hashCode = getFilters().hashCode(); return hashCode; } /** * Returns true if for every spec in this spec, there is a corresponding spec in the given spec that excludesSameModulesAs(). */ protected boolean implies(Set<AbstractModuleExclusion> miss1, Set<AbstractModuleExclusion> miss2) { if (miss1.isEmpty() || miss2.isEmpty()) { return false; } for (AbstractModuleExclusion thisSpec : miss1) { boolean found = false; for (AbstractModuleExclusion otherSpec : miss2) { if (thisSpec.excludesSameModulesAs(otherSpec)) { found = true; break; } } if (!found) { return false; } } return true; } }