package org.eclipse.aether.util.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 static java.util.Objects.requireNonNull;
  
  import org.eclipse.aether.version.Version;
  import org.eclipse.aether.version.VersionConstraint;
  import org.eclipse.aether.version.VersionRange;
  
  /**
   * A constraint on versions for a dependency.
   */
  final class GenericVersionConstraint
      implements VersionConstraint
  {
  
      private final VersionRange range;
  
      private final Version version;
  
      /**
       * Creates a version constraint from the specified version range.
       *
       * @param range The version range, must not be {@code null}.
       */
      public GenericVersionConstraint( VersionRange range )
      {
          this.range = requireNonNull( range, "version range cannot be null" );
          this.version = null;
      }
  
      /**
       * Creates a version constraint from the specified version.
       *
       * @param version The version, must not be {@code null}.
       */
      public GenericVersionConstraint( Version version )
      {
          this.version = requireNonNull( version, "version cannot be null" );
          this.range = null;
      }
  
      public VersionRange getRange()
      {
          return range;
      }
  
      public Version getVersion()
      {
          return version;
      }
  
      public boolean containsVersion( Version version )
      {
          if ( range == null )
          {
              return version.equals( this.version );
          }
          else
          {
              return range.containsVersion( version );
          }
      }
  
      @Override
      public String toString()
      {
          return String.valueOf( ( range == null ) ? version : range );
      }
  
      @Override
      public boolean equals( Object obj )
      {
          if ( this == obj )
          {
              return true;
          }
          if ( obj == null || !getClass().equals( obj.getClass() ) )
          {
              return false;
          }
 
         GenericVersionConstraint that = (GenericVersionConstraint) obj;
 
         return eq( range, that.range ) && eq( version, that.getVersion() );
     }
 
     private static <T> boolean eq( T s1, T s2 )
     {
         return s1 != null ? s1.equals( s2 ) : s2 == null;
     }
 
     @Override
     public int hashCode()
     {
         int hash = 17;
         hash = hash * 31 + hash( getRange() );
         hash = hash * 31 + hash( getVersion() );
         return hash;
     }
 
     private static int hash( Object obj )
     {
         return obj != null ? obj.hashCode() : 0;
     }
 
 }