Performance and security are primary concerns for any application. Because the Java language was designed to be compiled into a platform-independent bytecode format, much of the information contained in the source code remains in the bytecode, making it easy to decompile or reverse-engineer a Java application. This format can also contribute to larger file sizes, and with the limited resources of mobile devices, every byte saved in a MIDP application counts towards mobility and performance.
Obfuscators use a variety of methods to transform compiled code. Code obfuscation techniques include stripping object code of its symbol tables, or altering the names of variables and identifiers. Obfuscated programs are not only more difficult to decompile or reverse-engineer, they are also frequently smaller in size, improving performance and mobility as well as security.
You can add additional obfuscation parameters in the Addtional Obfuscation
Settings window.
The default obfuscator included with the IDE is ProGuard.
You can find more details about command parameters for this obfuscator at: