title: Creating a jar file from a Scala file
body: <p>I'm new to Scala and don't know Java. I want to create a jar file out of a simple Scala file. So I have my HelloWorld.scala, generate a HelloWorld.jar. </p>
  
  <p>Manifest.mf:</p>
  
  <pre><code>Main-Class: HelloWorld
  </code></pre>
  
  <p>In the console I run:</p>
  
  <pre><code>fsc HelloWorld.scala
  jar -cvfm HelloWorld.jar Manifest.mf HelloWorld\$.class HelloWorld.class
  java -jar HelloWorld.jar 
    =&gt; "Exception in thread "main" java.lang.NoClassDefFoundError: HelloWorld/jar"
  
  java -cp HelloWorld.jar HelloWorld 
    =&gt; Exception in thread "main" java.lang.NoClassDefFoundError: scala/ScalaObject
      at java.lang.ClassLoader.defineClass1(Native Method)
      at java.lang.ClassLoader.defineClass(ClassLoader.java:675)
      at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
      at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
      at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
      at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
      at java.security.AccessController.doPrivileged(Native Method)
      at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
      at java.lang.ClassLoader.loadClass(ClassLoader.java:316)
      at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:280)
      at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
      at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:374)
      at hoppity.main(HelloWorld.scala)
  </code></pre>