1. A method for optimizing JAVA builds by refactoring previously complied code comprising: identifying, at a device running a code building optimizer, a software program or software library that has completed a development process that has yet to be deployed on a platform or device; searching byte code of the software program or software library for string buffer objects subject to string buffer reuse; and at a plurality of points where string buffer reuse is possible as identified by the searching, performing a modification of the byte code, such that the modification replaces a call to build a new string buffer object with a call to an existing string buffer object and code setting length of the existing string buffer object to zero and appending new string characters this existing string buffer object, wherein a modified version of the byte code, per the performing of the modification at a plurality of points, is functionally equivalent to a pre-modified version of the byte code, yet creates fewer string buffer and character array objects thereby improving performance of the byte code when executed by a processor.