question: private byte [ ] lookupClassData ( String className ) throws ClassNotFoundException { byte [ ] data = null ; for ( String path : pathItems ) { String fileName = className . replace ( '.' , '/' ) + ".class" ; if ( isJar ( path ) ) data = loadJarData ( path , fileName ) ; else data = loadFileData ( path , fileName ) ; if ( data != null ) return data ; } throw new ClassNotFoundException ( ) ; }
target:  Search for a class file, and return class data if found.