public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof StandardPieURLGenerator)) {
            return false;
        }
        StandardPieURLGenerator that = (StandardPieURLGenerator) obj;
        if (!this.prefix.equals(that.prefix)) {
            return false;
        }
        if (!this.categoryParameterName.equals(that.categoryParameterName)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.indexParameterName, 
                that.indexParameterName)) {
            return false;
        }
        return true;