NPE in JarIndexWrapper if jar has no jar index

FULL PRODUCT VERSION :
java version "9-ea"
Java(TM) SE Runtime Environment (build 9-ea+115)
Java HotSpot(TM) Client VM (build 9-ea+115, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
Can't launch WebStart applications.
Seems identical to JDK-8154155 - but with a different stack trace. Don't know if the fix hasn't made it into build 115 as promised or if the fix is non-functional.

REGRESSION. Last worked in version 8u92

ADDITIONAL REGRESSION INFORMATION:
java version "9-ea"
Java(TM) SE Runtime Environment (build 9-ea+115)
Java HotSpot(TM) Client VM (build 9-ea+115, mixed mode)

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
See JDK-8154155

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
See JDK-8154155
ACTUAL -
See JDK-8154155

ERROR MESSAGES/STACK TRACES THAT OCCUR :
java.lang.NullPointerException
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(java.base@9-ea/Native Method)
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke(java.base@9-ea/NativeMethodAccessorImpl.java:62)
at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(java.base@9-ea/DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(java.base@9-ea/Method.java:531)
at com.sun.deploy.security.JarIndexWrapper.getJarFiles(jdk.deploy@9-ea/JarIndexWrapper.java:89)
at com.sun.deploy.security.DeployURLClassPath$JarLoader$1.run(jdk.deploy@9-ea/DeployURLClassPath.java:763)
at com.sun.deploy.security.DeployURLClassPath$JarLoader$1.run(jdk.deploy@9-ea/DeployURLClassPath.java:755)
at java.security.AccessController.doPrivileged(java.base@9-ea/Native Method)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.ensureOpen(jdk.deploy@9-ea/DeployURLClassPath.java:754)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.<init>(jdk.deploy@9-ea/DeployURLClassPath.java:743)
at com.sun.deploy.security.DeployURLClassPath$3.run(jdk.deploy@9-ea/DeployURLClassPath.java:429)
at com.sun.deploy.security.DeployURLClassPath$3.run(jdk.deploy@9-ea/DeployURLClassPath.java:419)
at java.security.AccessController.doPrivileged(java.base@9-ea/Native Method)
at com.sun.deploy.security.DeployURLClassPath.getLoader(jdk.deploy@9-ea/DeployURLClassPath.java:419)
at com.sun.deploy.security.DeployURLClassPath.getLoader(jdk.deploy@9-ea/DeployURLClassPath.java:393)
at com.sun.deploy.security.DeployURLClassPath.getResource(jdk.deploy@9-ea/DeployURLClassPath.java:251)
at com.sun.deploy.security.DeployURLClassLoader$1.run(jdk.deploy@9-ea/DeployURLClassLoader.java:285)
at com.sun.deploy.security.DeployURLClassLoader$1.run(jdk.deploy@9-ea/DeployURLClassLoader.java:282)
at java.security.AccessController.doPrivileged(java.base@9-ea/Native Method)
at com.sun.deploy.security.DeployURLClassLoader.findClass(jdk.deploy@9-ea/DeployURLClassLoader.java:281)
at com.sun.jnlp.JNLPClassLoader.findClass(jdk.javaws@9-ea/JNLPClassLoader.java:372)
at java.lang.ClassLoader.loadClass(java.base@9-ea/ClassLoader.java:486)
at java.lang.ClassLoader.loadClass(java.base@9-ea/ClassLoader.java:473)
at java.lang.ClassLoader.loadClass(java.base@9-ea/ClassLoader.java:419)
at com.sun.javaws.Launcher.doLaunchApp(jdk.javaws@9-ea/Launcher.java:1495)
at com.sun.javaws.Launcher.run(jdk.javaws@9-ea/Launcher.java:164)
at java.lang.Thread.run(java.base@9-ea/Thread.java:804)


REPRODUCIBILITY :
This bug can be reproduced always.

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See JDK-8154155
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