[hibernate-issues] [Hibernate-JIRA] Closed: (HBX-626) New meta tag for specifying the class that implements equals algorithm

New meta tag for specifying the class that implements equals algorithm ---------------------------------------------------------------------- Key: HBX-626 URL: http://opensource.atlassian.com/projects/hibernate/browse/HBX-626 Project: Hibernate Tools Type: Improvement

Components: hbm2java Versions: 3.1beta4 Reporter: David Leal

Just to suggest a usefull new meta tag in order to specify the way to implement the equal algorithm. Now the meta tags allow to specify which property will be considered on the equals method, but what about if I have a comlex algorithm for determine if two object are equals or not. The solution for the moment is to extend the generated domain class an override the equals method, another ugly solution would be modify the generated java class, which generate problems in order to mantain the code. My suggestion will be a meta attribute on the class node in order to define the which class will implement the equals method, for example: <class name="a.b.c.domain.Sample" table="sample"> <meta attribute="equal-class">a.b.c.domain.SampleEquals</meta> </class> so the generated class will be: public boolean equals(Object other) { return SampleEquals.isEquals(this, other); } where SampleEquals should be an utility class with a single static method: isEquals. Otherwise a more professional solution could be a regular class that should implement a given interface for implementing the equals algorithm. Now on the SampleEquals.isEquals method, your are free to implement a very complicated algorithm about how to make a desition if to objects are equals or not. Thanks in advance, David