New Features

Implemented AGC-based kernel read/write primitives to allow write access to kernel data on firmware 6.00+. Big thanks to flat_z.
Added the payload to activate Debug Settings menu. Credit to CryoNumb.
Various SDK improvements and refactorings.
Added output of version numbers for JAR loader and for payloads (based on Maven project version).

Notes

Release v4.0.0 was yanked as it contained a critical bug on firmware 7.00+.
New payloads are not compatible with previous JAR Loader version and vice-versa.
Full ISO includes a menu and all the JARs as of this release. Trimmed ISO includes only the remote JAR loader, payloads need to be sent over network.
Full ISO does not include jailbreak and klogserver JARs as jailbreak is not working well with the menu loader.
Some directories are not accessible in BD-J, even with jailbreak. This is a known issue, walkaround for this restriction has not yet been found.

UMTX bug implementations from flat_z, Cryptogenic and cheburek3000 adapted to this SDK. Each one of them can be used to obtain kernel read/write. Note: UMTX1 is the recommended payload. As stability improves, other implentations will be deprecated and eventually removed.
Byepervisor implementation from Cryptogenic.
Kernel dumper. Once kernel r/w is obtained, send this payload to dump the kernel. If byepervisor was run first, it will dump text and data. Otherwise, only data will be sent. Use netcat on a computer to receive the kernel binary by connecting to the PS5 on port 5656.
Jailbreak implementation which makes BD-J process run with superuser and escapes it from /app0 jail.
FTP server (with root access after jailbreak).
Klog server. Not very stable when a client is connected to it.
Debug Settings. Activates/deactivates debug settings (deactivation only works within initial BD-J process).
Samples:
- Mini tennis game.
- System properties printer.
- Dump current classpath of JVM, including java.base module (may not work on all firmwares).
- List of all directories in the filesystem using native calls.