Here are a number of reasons why one should use this environment.
With the code being written purely in Java, a port to another system requires modifying the compiler to support that system along with having a backend which interacts with the hardware and software. This is a bonus, because due to Java's consistency across platforms this means that the code that runs the virtual machine itself is written for the virtual machine itself. This means that there are no quirks to workaround or having to require the proprocessor to differentiate and flag differing platforms.
Java and the virtual machine it runs on is intended to be write once and run anywhere. SquirrelJME is intended to take the lightest variant of Java and aims to be 100% compatible with it. There are many variations in software and hardware that the environment inside of Java is layered on top of. This provides a single execution environment and in the general case programs which run inside of it could not tell the difference if the platform is 8-bit or 4096-bit. This means that