public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof AbstractXYItemLabelGenerator)) {
            return false;
        }
        AbstractXYItemLabelGenerator that = (AbstractXYItemLabelGenerator) obj;
        if (!this.formatString.equals(that.formatString)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.xFormat, that.xFormat)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.xDateFormat, that.xDateFormat)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.yFormat, that.yFormat)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.yDateFormat, that.yDateFormat)) {
            return false;
        }
        if (!this.nullYString.equals(that.nullYString)) {
        	return false;
        }
        return true;