Java has been through three major architectural incarnations. The 1.0x release series was first. Release 1.1x reworked the architecture, resulting in some APIs being deprecated. Release 1.2 further enhanced the architecture. This release was branded as Java 2.
The Java 2 SDK v1.2.2 will not work with Red Hat 7.1. Users who want to run the Java 2 SDK on Red Hat 7 can try using new version Java 2 SDK v1.3.0 for Linux. The Java 2 SDK v1.3.0 was tested on Red Hat 6.1 and is not officially supported on Red Hat 7, but there are no known problems with running the Java 2 SDK v1.3.0 on Red Hat 7 as long as the Classic VM is not used.
The Java 2 brand is split into editions that target solution levels as shown in Table 6-1.