equals and hashCode methods

[Adam Hardy]

I put a superclass on all my entities for a couple of general properties that 
they all share, and now I'm considering putting my equals() and hashCode() 
methods into the superclass as well, with reflection to loop over the array of 
child methods, calling whatever POJO getters are present.

The advantage in terms of not needing to maintain the equals, hashCode and 
toString methods on every entity is quite attractive, but I'm worried about

(a) performance
(b) any nasty surprises it might cause in JPA entity management

With (a), performance will be hit if an entity has large collections of 
one-to-many or many-to-many related entities. I might be able to get around 
quite easily though.

With (b) it seems more problematic, for instance calling the equals() might get 
stuck in an endless loop if I have any circular relationships in my model, which 
would otherwise be benign if only loaded by lazy loading.

Sorry that this isn't directly an OpenJPA question.

This is the kind of thing I'm thinking of:

public boolean equals(Object object) {
    if (this == object) return true;
    if (object == null) return false;
    if (!(object instanceof TradeHistory)) return false;
    TradeHistory other = (TradeHistory) object;
    boolean equal = false;
    Method[] methods = this.getClass().getMethods();
    for (int i = 0; i < methods.length; i++) {
        Method method = methods[i];
        if (method.getName().equalsIgnoreCase("GETCLASS")) continue;
        if ((method.getName().startsWith("get"))
            && (method.getParameterTypes().length == 0)) {
            try {
                Method otherMethod =
                    other.getClass().getMethod(method.getName(),
                        new Class[] {});
                equal &=
                    isEqual(method.invoke(this, new Object[] {}), otherMethod
                        .invoke(other, new Object[] {}));
            }
            catch (Exception e) {
            }
        }
    }
    return equal;
}