I'm trying to build my jwrapper application, and it fails with
WARNING: Error on output: java.io.IOException: bad class major version for Java 7 invokedynamic
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* BUILD FAILED *
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** Error Trace:
java.io.IOException: bad class major version for Java 7 invokedynamic
at com.sun.java.util.jar.pack.PackageWriter.writeByteCodes(PackageWriter.java:1657)
at com.sun.java.util.jar.pack.PackageWriter.writeMembers(PackageWriter.java:1227)
at com.sun.java.util.jar.pack.PackageWriter.writeClassesAndByteCodes(PackageWriter.java:1202)
at com.sun.java.util.jar.pack.PackageWriter.write(PackageWriter.java:79)
at com.sun.java.util.jar.pack.PackerImpl$DoPack.flushPackage(PackerImpl.java:602)
at com.sun.java.util.jar.pack.PackerImpl$DoPack.flushAll(PackerImpl.java:556)
at com.sun.java.util.jar.pack.PackerImpl$DoPack.run(PackerImpl.java:492)
at com.sun.java.util.jar.pack.PackerImpl.pack(PackerImpl.java:98)
at jwrapper.pack200.Pack200Compressor.compressFileToOutputStream(Pack200Compressor.java:225)
at jwrapper.archive.Archive.addFileToStream(Archive.java:422)
at jwrapper.archive.Archive.addFile(Archive.java:159)
at jwrapper.archive.Archive.addFile(Archive.java:103)
at jwrapper.archive.LaunchableArchive.addFile(LaunchableArchive.java:43)
at jwrapper.archive.LaunchableArchive.addFile(LaunchableArchive.java:29)
at jwrapper.JWrapperCompiler.main(JWrapperCompiler.java:2827)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at SecureRunner2.<init>(SecureRunner2.java:452)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:408)
at SecureRunner1.<init>(SecureRunner1.java:410)
at SecureRunner1.<init>(SecureRunner1.java:227)
at SecureRunner1.main(SecureRunner1.java:52)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
It used to build with no problems at all, and nothing changed (not the jwrapper.xml file, which can be attached if that would be helpful, nor the java version jdk1.8.0_31, or even the code being wrapped!). What has me baffled (yes, I googled for invokedynamic, java 7, jwrapper, etc and various combinations of those), was how Java 7's even involved. I have no instances of Java 7 on the system -- I'm packing 1.8.0_31 JRE's, and am using jdk1.8.0_31 to run the process.
The reference to Java 7 is because the 'invokedynamic' instruction was added to the JVM in Java 7.
So it looks like the code is using 'invokedynamic' but the class file version is Java 6 or earlier (so the major version is wrong).