A number of recent changes have occurred to the JDK build process as part of the SE-Embedded integration. The build variables used in those CRs need to be documented.

- BUILD_CLIENT_ONLY
- CROSS_COMPILE_ARCH
- EXTRA_CFLAGS
- USE_ONLY_BOOTDIR_TOOLS
- HOST_CC
- COMPRESS_JARS
- LIBZIP_CAN_USE_MMAP
- BUILD_HEADLESS_ONLY
- JAVASE_EMBEDDED
Also ALT_OPENWIN_HOME.