sun.net.www.protocol.jar.URLJarFile$URLJarFileEntry class extends java.util.jar.JarEntry. URLJarFile$URLJarFileEntry overrides the getCertificates() and getCodeSigners() methods. The implementation in these overriden methods merely clone the arrays returned by the JarEntry counterparts. This cloning is not needed because these 2 methods on JarEntry already return cloned instances of those arrays. That detail of JarEntry is now specified in JDK-8370688.