title: java classloader runtime error in netbeans
body: <p>When I run my project it shows this error</p>
  
  <pre><code>run:
  `java.lang.SecurityException:` Prohibited package name: java.course
      at java.lang.ClassLoader.preDefineClass(ClassLoader.java:659)
      at java.lang.ClassLoader.defineClass(ClassLoader.java:758)
      at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
      at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
      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)
  Error: A JNI error has occurred, please check your installation and try again
  Exception in thread "main" Java Result: 1
  BUILD SUCCESSFUL (total time: 2 seconds)
  </code></pre>
  
  <p><strong>What can i do to solve this problem ?</strong></p>
  
  <p><em>Note:-Please simplify explanation because I'm still initially structured in the programming department and I am still in the tutorial.</em></p>