Implementing the setEntityContext and unsetEntityContext Methods

An entity bean instance uses this method to retain a reference to its context. Entity beans have contexts that the container maintains and makes available to the beans. The bean may use the methods in the entity context to retrieve information about the bean, such as security, and transactional role. Refer to the Enterprise JavaBeans specification from Sun Microsystems for the full range of information that you can retrieve about the bean from the context.

The container invokes the setEntityContext method, after it first instantiates the bean, to enable the bean to retrieve the context. The container will never call this method from within a transaction context. If the bean does not save the context at this point, the bean will never gain access to the context.

When the container calls this method, it passes the reference of the EntityContext object to the bean. The bean can then store the reference for later use. The following example shows the bean saving the context in the this.ctx variable.

You use this method to obtain a reference to the context of the bean. Entity beans have entity contexts that the container maintains and makes available to the beans. The bean may use the methods in the entity context to make callback requests to the container.

Example 13-10 shows an entity bean saving the session context in the entityctx variable.

import javax.ejb.*;

public class MyBean implements EnityBean {
   EntityContext entityctx;

   public void setEntityContext(EntityContext ctx) {
      entityctx = ctx;   // entity context is stored in instance variable
   }

    public void unsetEntityContext() {
        entityctx = null;
    }

   // other methods in the bean
}