title: Error while running libgdx example
body: <p>I am new to libgdx.Just tried running the <code>libgdx</code> example i get strange error it says:</p>
  
  <pre><code>[2013-03-22 12:08:35 - ObjLoaderUsingLibGdx] Dx 1 error; aborting
  [2013-03-22 12:08:35 - ObjLoaderUsingLibGdx] Conversion to Dalvik format failed with error 1
  [2013-03-22 12:10:59 - ObjLoaderUsingLibGdx] Dx 
  trouble processing "java/io/BufferedInputStream.class":
  
  Ill-advised or mistaken usage of a core class (java.* or javax.*)
  when not building a core library.
  
  This is often due to inadvertently including a core library file
  in your application's project, when using an IDE (such as
  Eclipse). If you are sure you're not intentionally defining a
  core class, then this is the most likely explanation of what's
  going on.
  
  However, you might actually be trying to define a class in a core
  namespace, the source of which you may have taken, for example,
  from a non-Android virtual machine project. This will most
  assuredly not work. At a minimum, it jeopardizes the
  compatibility of your app with future versions of the platform.
  It is also often of questionable legality.
  
  If you really intend to build a core library -- which is only
  appropriate as part of creating a full virtual machine
  distribution, as opposed to compiling an application -- then use
  the "--core-library" option to suppress this error message.
  
  If you go ahead and use "--core-library" but are in fact
  building an application, then be forewarned that your application
  will still fail to build or run, at some point. Please be
  prepared for angry customers who find, for example, that your
  application ceases to function once they upgrade their operating
  system. You will be to blame for this problem.
  
  If you are legitimately using some code that happens to be in a
  core package, then the easiest safe alternative you have is to
  repackage that code. That is, move the classes in question into
  your own package namespace. This means that they will never be in
  conflict with core system classes. JarJar is a tool that may help
  you in this endeavor. If you find that you cannot do this, then
  that is an indication that the path you are on will ultimately
  lead to pain, suffering, grief, and lamentation.
  </code></pre>
  
  <p>I dont know what is the problem i have followed <a href="http://chrismweb.com/2011/10/18/how-to-start-creating-android-games-using-the-libgdx-game-development-framework/" rel="nofollow">this tutorial</a> for getting started. can someone point out whats this error is all about. What can be the source of this error i am not able to understand followed all the steps out there imported all the lib and did build path as well</p>