A Java Exception Has Occurred When Opening a JAR File

This tutorial demonstrates how to solve Java’s A java exception has occurred.

A java exception has occurred When Opening .jar File

The Java exception is a condition that makes it impossible for JVM to run the Java code, resulting in the program’s crashing. These exceptions occur within the Java code when developers fail to fix the bugs or they don’t have any knowledge about subsequent problems.

These exceptions can occur without any action from the developers.

The error A java exception has occurred when opening or creating a .jar file occurs when we are trying to compile the Java program with a higher version than the version required to open a particular .jar file. The error may look something like this:

Exception in thread
    "main" java.lang.UnsupportedClassVersionError : Java_Exception
    : Unsupported major.minor version 52.0 at java.lang.ClassLoader
          .defineClass1(
              Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java : 800) at java
          .security.SecureClassLoader.defineClass(SecureClassLoader.java : 142) at java.net
          .URLClassLoader.defineClass(URLClassLoader.java : 449) at java.net.URLClassLoader
          .access$100(URLClassLoader.java : 71) at java.net.URLClassLoader$1
          .run(URLClassLoader.java : 361) at java.net.URLClassLoader$1
          .run(URLClassLoader.java : 355) at java.security.AccessController
          .doPrivileged(
              Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java : 354) at java
          .lang.ClassLoader.loadClass(ClassLoader.java : 425) at sun.misc.Launcher$AppClassLoader
          .loadClass(Launcher.java : 308) at java.lang.ClassLoader
          .loadClass(ClassLoader.java : 358) at sun.launcher.LauncherHelper.checkAndLoadMain(
              LauncherHelper.java : 482)

The solutions for this error are:

1. Upgrade the .jar file to the JDK version or degrade the JDK to a .jar file.
2. If a specific feature of JDK is not used, which was used to compile before, set their target to the previous version.

There are several types of Java exceptions. These exceptions are handled using try-catch blocks.

This means if an exception is going to occur, the try-catch block can help us to save the program from crashing.