title: Getting Exception in thread "main" java.lang.VerifyError: class com.google.gwt.dev.HostedModeBase$ArgHandlerNoServerFlag
body: <p>I am trying to upgrade my application from GWT 2.0 to 2.7.0 and getting below exception. I am using the below mentioned jars. What is the reason for this exception ? Is there any migration guide or document that i can refer for upgrading to 2.7 gwt version ?</p>
  
  <pre><code>Exception in thread "main" java.lang.VerifyError: class com.google.gwt.dev.HostedModeBase$ArgHandlerNoServerFlag overrides final method getPurpose.()Ljava/lang/String;
  at java.lang.ClassLoader.defineClass1(Native Method)
  </code></pre>
  
  <p><strong>Jars used :</strong></p>
  
  <p>gwt-user-2.7.0.jar</p>
  
  <p>get-dev-2.7.0.jar</p>
  
  <p>gwt-servlet-2.7.0.jar</p>
  
  <p>gwt-dev-windows.jar</p>
  
  <p>gwtext.jar</p>