When developing an entity bean you can take advantage of the bean's relationship with the container to execute logic and optimizations outside the context of the bean's core logic. As the container creates and pools an instance, assigns data to it, executes bean methods, and eventually removes the instance, the container provides opportunities for your code to execute. This topic provides an overview of an entity bean's life cycle, pointing out some of these opportunities.

The following figure shows the life cycle of an entity bean. An entity bean has the following three states:

• Does not exist. In this state, the bean instance simply does not exist.
• Pooled state . When WebLogic server is first started, several bean instances are created and placed in the pool. A bean instance in the pooled state is not tied to particular data, that is, it does not correspond to a record in a database table. Additional bean instances can be added to the pool as needed, and a maximum number of instances can be set.
• Ready state. A bean instance in the ready state is tied to particular data, that is, it represents an instance of an actual business object.

The various state transitions as well as the methods available during the various states are discussed below.