/*
    * Copyright (C) 2008 The Guava 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 com.google.common.collect.testing.features;
  
  import com.google.common.annotations.GwtCompatible;
  import com.google.common.collect.testing.Helpers;
  
  import java.util.Collections;
  import java.util.Set;
  
  /**
   * Encapsulates the constraints that a class under test must satisfy in order
   * for a tester method to be run against that class.
   *
   * @author George van den Driessche
   */
  @GwtCompatible
  public final class TesterRequirements {
    private final Set<Feature<?>> presentFeatures;
    private final Set<Feature<?>> absentFeatures;
  
    public TesterRequirements(
        Set<Feature<?>> presentFeatures, Set<Feature<?>> absentFeatures) {
      this.presentFeatures = Helpers.copyToSet(presentFeatures);
      this.absentFeatures = Helpers.copyToSet(absentFeatures);
    }
  
    public TesterRequirements(TesterRequirements tr) {
      this(tr.getPresentFeatures(), tr.getAbsentFeatures());
    }
  
    public TesterRequirements() {
      this(Collections.<Feature<?>>emptySet(),
          Collections.<Feature<?>>emptySet());
    }
  
    public final Set<Feature<?>> getPresentFeatures() {
      return presentFeatures;
    }
  
    public final Set<Feature<?>> getAbsentFeatures() {
      return absentFeatures;
    }
  
    @Override public boolean equals(Object object) {
      if (object == this) {
        return true;
      }
      if (object instanceof TesterRequirements) {
        TesterRequirements that = (TesterRequirements) object;
        return this.presentFeatures.equals(that.presentFeatures)
            && this.absentFeatures.equals(that.absentFeatures);
      }
      return false;
    }
  
    @Override public int hashCode() {
      return presentFeatures.hashCode() * 31 + absentFeatures.hashCode();
    }
  
    @Override public String toString() {
      return "{TesterRequirements: present="
          + presentFeatures + ", absent=" + absentFeatures + "}";
    }
  
    private static final long serialVersionUID = 0;
  }