B4J Question Remote debugging with B4J-Bridge Issue

[gregchao]

I am having a problem installing the B4J-Bridge. I get this error when I try to install on the MAC. Any help would be welcome.

Last login: Sat Jul 17 21:58:53 on ttys000
sandrachao@Sandras-MBP ~ % java -version
java version "1.8.0_191"
Java(TM) SE Runtime Environment (build 1.8.0_191-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.191-b12, mixed mode)
sandrachao@Sandras-MBP ~ % cd downloads/
sandrachao@Sandras-MBP downloads % java -jar b4jbridge.jar
Error: Unable to access jarfile b4jbridge.jar
sandrachao@Sandras-MBP downloads % java -jar b4j-bridge.jar
Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.UnsupportedClassVersionError: b4j/example/main has been compiled by a more recent version of the Java Runtime (class file version 53.0), this version of the Java Runtime only recognizes class file versions up to 52.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:468)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:74)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:362)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:495)

 

[EnriqueGonzalez]

b4j/example/main has been compiled by a more recent version of the Java Runtime

here says that you are using 1.8 jdk and the compiled jar (b4j bridge) is for jdk 11, try using jdk 11 and it will work.

 

[Erel]

Best to follow the java related instructions from this thread: https://www.b4x.com/android/forum/threads/macsigner-building-notarized-mac-packages.130890/#content
Other versions of Java will not be signed and will be more difficult to use.