“Invalid signature file” when attempting to run a .jar

Question

My java program is packaged in a jar file and makes use of an external jar library, bouncy castle. My code compiles fine, but running the jar leads to the following error:

Answer 1

If you're getting this when trying to bind JAR files for a Xamarin.Android bindings project like so:

JARTOXML : warning J2XA006: missing class error was raised while reflecting com.your.class : Invalid signature file digest for Manifest main attributes

Just open the JAR files using Winzip and delete the meta-inf directories. Rebuild - job done

Answer 2

Error: A JNI error has occurred, please check your installation and try again Exception in thread "main" java.lang.SecurityException: Invalid signature file digest for Manifest main attributes at sun.security.util.SignatureFileVerifier.processImpl(SignatureFileVerifier.java:314) at sun.security.util.SignatureFileVerifier.process(SignatureFileVerifier.java:268) at java.util.jar.JarVerifier.processEntry(JarVerifier.java:316) at java.util.jar.JarVerifier.update(JarVerifier.java:228) at java.util.jar.JarFile.initializeVerifier(JarFile.java:383) at java.util.jar.JarFile.getInputStream(JarFile.java:450) at sun.misc.URLClassPath$JarLoader$2.getInputStream(URLClassPath.java:977) at sun.misc.Resource.cachedInputStream(Resource.java:77) at sun.misc.Resource.getByteBuffer(Resource.java:160) at java.net.URLClassLoader.defineClass(URLClassLoader.java:454) at java.net.URLClassLoader.access$100(URLClassLoader.java:73) at java.net.URLClassLoader$1.run(URLClassLoader.java:368) at java.net.URLClassLoader$1.run(URLClassLoader.java:362) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:361) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:495)

What helped me (IntelliJ IDEA 2016.3): File -> Project Structure -> Artifacts -> Add JAR -> Select Main Class -> Choose "copy to the output directory and link via manifest" -> OK -> Apply -> Build -> Build Artifacts... -> Build

Answer 3

Compare the folder META-INF in new jar with old jar (before you added new libraries). It is possibility that there will be new files. If yes, you can remove them. It should helps. Regards, 999michal