J2EE.6.1 Required APIs

J2EE application components execute in runtime environments provided by the containers that are a part of the J2EE platform. The J2EE platform supports four separate types of containers, one for each J2EE application component type ”application client containers, applet containers, web containers for servlets and JSP pages, and enterprise bean containers. The containers provide all application components with the Java 2 Platform, Standard Edition, v1.2 (J2SE) APIs, which include the following enterprise APIs:

• JavaIDL API

• JDBC Core API

The containers for all application component types must provide Java Compatible runtime environments. In particular, a J2EE product must provide an applet execution environment that is J2SE 1.2 compatible. Since typical browsers don't yet provide such support, the J2EE platform may make use of the Java Plugin to provide the required applet execution environment. Use of the Java Plugin is not required, but a J2EE product is required to provide a J2SE 1.2 compatible applet execution environment.

The specifications for the J2SE components are available at http://java.sun.com/products/jdk/1.2/docs/.

The J2EE platform also includes a number of Java standard extensions. Table J2EE.6-1 indicates which standard extensions are required to be available in each type of container. Table J2EE.6-1 also indicates the required version of the standard extension.

Table J2EE.6-1. J2EE-Required Java Standard Extensions

Standard Extension	App Client	Applet	Web	EJB
JDBC 2.0 Extension	Y	N	Y	Y
RMI-IIOP 1.0	Y	N	Y	Y
EJB 1.1	Y [a]	N	Y [b]	Y
Servlets 2.2	N	N	Y	N
JSP 1.1	N	N	Y	N
JMS 1.0	Y	N	Y	Y
JNDI 1.2	Y	N	Y	Y
JTA 1.0	N	N	Y	Y
JavaMail 1.1	N	N	Y	Y
JAF 1.0	N	N	Y	Y

^[a] Application clients can only make use of the enterprise bean client APIs.

^[b] Servlets and JSP pages can only make use of the enterprise bean client APIs.

The APIs included in the J2EE platform must be included in their entirety. Definitions for all classes and interfaces required by the specifications must be included. Some of the APIs include interfaces that are intended to be implemented by an application server. In some cases a J2EE product is not required to provide objects that implement such interfaces. Nonetheless, the definitions of such interfaces must be included in the J2EE platform.