Work on bug 1219 and bug 1231 disclosed possible situations where executables (loading native libraries or launching executables) are not supported within the user's temporary folder(s). TempFileCache and TempJarCache provide functionality beyond supporting native library loading, hence implementation and usage shall consider this.
Resolved as described. TempFileCache & TempJarCache 'forExecutable' suitability can be queried and implementation has adapted accordingly.