private String[] findSupportedFileExtensions() { final String compilerImpl = getCompiler(); final CompilerAdapter adapter = nestedAdapter != null ? nestedAdapter : CompilerAdapterFactory.getCompiler(compilerImpl, this, createCompilerClasspath()); String[] extensions = null; if (adapter instanceof CompilerAdapterExtension) { extensions = ((CompilerAdapterExtension) adapter).getSupportedFileExtensions(); } if (extensions == null) { extensions = new String[] {"java"}; } // now process the extensions to ensure that they are the // right format for (int i = 0; i < extensions.length; i++) { if (!extensions[i].startsWith("*.")) { extensions[i] = "*." + extensions[i]; } } return extensions; }