private boolean isZip ( JarEntry entry ) throws IOException { try ( InputStream entryInputStream = sourceFatJar . getInputStream ( entry ) ) { try ( ZipInputStream zipInputStream = new ZipInputStream ( entryInputStream ) ) { ZipEntry ze = zipInputStream . getNextEntry ( ) ; if ( ze == null ) { return false ; } return true ; } } }
Check whether the jar entry is a zip regardless of the extension .