equals implementation with proxies

bligny · **Posted:** Mon Oct 20, 2003 12:27 pm

I have a root persistent class with a default implementation of the equals(...) method.
It assumes that two persistent objects are equals if:
- they have the same identifier value
- AND share the same class

Code:

public boolean equals(Object obj) {
    Persistent other = (Persistent) obj;
    boolean sameId = this.getId().equals( other.getId() );
    boolean sameClazz = this.getClass().equals( other.getClass() );
    return (sameId && sameClazz);
}

Problem: when working with proxies, the other object to compare with (obj) may sometimes be of a different "physical " class (e.g. a cglib
class) although they share the same "logical" class...
Therefore, equals return false :-(

Any idea/hint/recommendation for having a good implementation which works in all cases ?

Thanks in advance,

Bernard.

emmanuel · **Posted:** Mon Oct 20, 2003 5:26 pm

try instanceof instead of getClass().equals

bligny · **Posted:** Tue Oct 21, 2003 4:33 am

Yes, it works fine !
(indeed CGLIB proxies are subclasses of the "concrete" class)

This gives:

Code:

public boolean equals(Object obj) {
    Entity other = (Entity) obj;
    boolean sameId = this.getId().equals( other.getId() );
    boolean sameClazz = ( this.getClass().isInstance(other) );
    return (sameId && sameClazz);
}

Thanks a lot.