Each SE JRE is comprised of the base J9VM+JIT JRE and the OS/processor port of: (i) either the entire Java 5 compatible Harmony class library from Apache.org or a subset of Harmony API packages needed by Java applications of a given customer or other components of the SE JRE (see below) or because of the manner in which the SE JRE will be used; (ii) a "glue layer" of special Apogee-created Java classes that make the ports of Java 5 compatible Harmony APIs work with the port of J2ME compatible J9VM; and (iii) customer-requested optional components, such as:

• The Java 5 or J2ME compatible client client-side runtimes from IBM or providers of open-source Java software, for example the J2SE-level Equinox OSGi R4 runtime.
• The Java 5 or J2ME compatible application level packages from providers of open-source Java software, for example the Tomcat servlet container from Apache.org.
• IBM's or Apogee's implementation of such API packages defined by J2ME JSRs that do not have the functionally equivalent API packages in Harmony.

Each SE JRE accepts and runs the JAR files of Java applications in Java 5 format, and can include the implementations of customer-requested Java 5 features, such as: Enhanced "for Loop", Static Import, Autoboxing/Unboxing, Varargs, Typesafe Enums, Generics, Assertions, bit manipulation operations, extended math, Serialization, Process builder, Formatter, Collections Framework, Metadata (Annotations), high precision timing support, and Reflections.