A fuzzed jar file causes an NPE in JarFile::verifiableEntry due to
access to a null pointer.

java JarTest npe_ze_null.jar javax/inject/Singleton.class
[...]
Exception in thread "main" java.lang.NullPointerException: Cannot invoke
"java.util.zip.ZipEntry.getName()" because "ze" is null
at java.base/java.util.jar.JarFile.verifiableEntry(JarFile.java:863)
at java.base/java.util.jar.JarFile.getInputStream(JarFile.java:853)
at JarTest.main(JarTest.java:18)

private JarEntry verifiableEntry(ZipEntry ze) {
        if (ze instanceof JarFileEntry) {
            // assure the name and entry match for verification
            return ((JarFileEntry)ze).realEntry();
        }
        ze = getJarEntry(ze.getName()); <======
        if (ze instanceof JarFileEntry) {
            return ((JarFileEntry)ze).realEntry();
        }
        return (JarEntry)ze;
    }