private static void convertMappings( JarFile sourceJar, JarFile destJar, Mappings mappings, Map<String,String> fallbackMatching )
{
// index jars
System.out.println( "Indexing source jar..." );
JarIndex sourceIndex = new JarIndex();
sourceIndex.indexJar( sourceJar, false );
System.out.println( "Indexing dest jar..." );
JarIndex destIndex = new JarIndex();
destIndex.indexJar( destJar, false );
TranslatingTypeLoader sourceLoader = new TranslatingTypeLoader( sourceJar, sourceIndex );
TranslatingTypeLoader destLoader = new TranslatingTypeLoader( destJar, destIndex );