Using Object Identity

In a Java application, object identity is preserved if each object in memory is represented by one, and only one, object instance. Multiple retrievals of the same object return references to the same object instance - not multiple copies of the same object.

Maintaining object identity is extremely important when the application's object model contains circular references between objects. You must ensure that two are referencing each other directly, rather than copies of each other. Object identity is important when multiple parts of the application may be modifying the same object simultaneously.

Turn identity off when object identity is not important (for example, for read-only objects).