}

        @Override
        public boolean equals( Object obj )
        {
            if ( obj == this )
            {
                return true;
            }
            else if ( !( obj instanceof Key ) )
            {
                return false;
            }
            Key that = (Key) obj;
            return artifact.getArtifactId().equals( that.artifact.getArtifactId() )
                && artifact.getGroupId().equals( that.artifact.getGroupId() )
                && artifact.getExtension().equals( that.artifact.getExtension() )
                && artifact.getClassifier().equals( that.artifact.getClassifier() );
        }

        @Override
        public int hashCode()
        {

    public static boolean equalsId( Artifact artifact1, Artifact artifact2 )
    {
        if ( artifact1 == null || artifact2 == null )
        {
            return false;
        }
        if ( !eq( artifact1.getArtifactId(), artifact2.getArtifactId() ) )
        {
            return false;
        }
        if ( !eq( artifact1.getGroupId(), artifact2.getGroupId() ) )
        {
            return false;
        }
        if ( !eq( artifact1.getExtension(), artifact2.getExtension() ) )
        {
            return false;
        }
        if ( !eq( artifact1.getClassifier(), artifact2.getClassifier() ) )
        {
            return false;
        }
        if ( !eq( artifact1.getVersion(), artifact2.getVersion() ) )