title: Java program does not run and throws an error about classes
body: <p>So I want to run my just compiled Start.class file that I compiled from Start.java. The problem is that it will throw this error:</p>
  
  <pre><code>java Start 
  Exception in thread "main" java.lang.NoClassDefFoundError: Start (wrong name: files/Start)
      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)
  </code></pre>
  
  <p>I have written the program in Eclipse and I want to run it from a Terminal. What is the problem here?</p>
  
  <p>New error: </p>
  
  <pre><code>java files.Start http://mirror.symnds.com/software/Apache/tomcat/tomcat-7/v7.0.53/bin/apache-tomcat-7.0.53.zip
  Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/io/IOUtils
      at files.Start.main(Start.java:93)
  Caused by: java.lang.ClassNotFoundException: org.apache.commons.io.IOUtils
      at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
      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)
      ... 1 more
  </code></pre>