JavaHL gets its configuration information from the same locations as the command line, although there is an option in JavaHL to override the default file system location to a user-specified location. However, the configuration itself is still stored in the file system. This makes it difficult for a tool like Subclipse to provide the user with a nice UI to enter this same sort of configuration and it also makes it impossible for Subclipse to store settings on a per-project basic which can be nice when working in a mixture of open source and internal projects. What I would like to see is a new API where we can pass into JavaHL some kind of object that contains configuration information. This information would be merged with the existing information as the top-layer in the hierarchy, which I understand to be a current feature of the configuration files. A secondary request would likely be to have a method call that could create one of these new configuration objects based on the current configuration files. We could use this to initialize the GUI with the current settings in the file. This would not be a must-have feature.