US Patent 7340719 Methods and apparatus to preserve software modifications

A code generator utilizes a “generated_source” directory to store corresponding machine-generated software code. A “modified_source” directory stores user-written modifications associated with software generated by the code generator. During code generation, the code generator checks the modified_source directory for a class presently being generated by the code generator. If there are no user modifications (stored in the modified_source directory) associated with the class being processed, the code generator creates an implementation of the class. If the modified_source directory contains an implementation of the class being processed, the code generator creates an implementation of a base class for the class being processed. The base class is created in the generated_source directory, preserving the class created by the user.