title: Exception while using JWrapper
body: <p>I'm trying to build an exe from jar file using jWrapper . Why am i getting the error as shown in the below on trying to generate exe using JWrapper? pls help</p>
  
  <pre><code>C:\Documents and Settings\Administrator&gt;java  -jar G:\IMS\jwrapper-00018512673.j
  ar  G:\IMS\app.xml
  JWrapper 00018512673
  JWrapperCompiler started
  [Config] Building file is G:\IMS\app.xml
  [Updates] Checking for updates...
  java.lang.reflect.InvocationTargetException
          at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
          at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
          at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
          at java.lang.reflect.Method.invoke(Unknown Source)
          at SecureRunner2.&lt;init&gt;(SecureRunner2.java:464)
          at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
  
          at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
  
          at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Sou
  rce)
          at java.lang.reflect.Constructor.newInstance(Unknown Source)
          at SecureRunner1.&lt;init&gt;(SecureRunner1.java:422)
          at SecureRunner1.&lt;init&gt;(SecureRunner1.java:227)
          at SecureRunner1.main(SecureRunner1.java:52)
          at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
          at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
          at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
          at java.lang.reflect.Method.invoke(Unknown Source)
          at jwrapper.launch.JWCompiler.main(JWCompiler.java:99)
  Caused by: java.lang.NullPointerException
          at jwrapper.JWrapperCompiler.main(JWrapperCompiler.java:458)
          ... 17 more
  [Updates] Update check: 18512673 vs 18473665 (online)
  </code></pre>
  
  <p>my app.xml file</p>
  
  <pre><code>&lt;JWrapper&gt;
  
      &lt;!-- This tells JWrapper the name of your app bundle --&gt;
      &lt;BundleName&gt;MinimalApp&lt;/BundleName&gt;
  
      &lt;!-- This bit defines a virtual app - your app bundle can have one of these or a bunch of them --&gt;
      &lt;App&gt;
  
          &lt;!-- The name of the app that launches --&gt;
          &lt;Name&gt;tx&lt;/Name&gt;
  
          &lt;!-- The logo for the app, we automatically scale and convert it to OS specific formats --&gt;
  
  
          &lt;!-- The Java main class for your app --&gt;
          &lt;MainClass&gt;ims.init.Selector&lt;/MainClass&gt;
  
          &lt;!-- Any static parameters you want to pass in to your main method --&gt;
          &lt;Param&gt;one&lt;/Param&gt;
          &lt;Param&gt;two&lt;/Param&gt;
  
      &lt;/App&gt;
  
      &lt;!-- This tells JWrapper what languages your app uses so JWrapper can let the user choose (if its more than one) --&gt;
      &lt;SupportedLanguages&gt;en,fr&lt;/SupportedLanguages&gt;
  
      &lt;!-- If your app needs to run elevated (as admin) on Windows you can specify that here --&gt;
      &lt;WindowsElevation&gt;None&lt;/WindowsElevation&gt;
  
      &lt;!-- This app installs itself for the current user, you can also install for all users or run as a temporary executable --&gt;
      &lt;InstallType&gt;CurrentUser&lt;/InstallType&gt;
  
      &lt;!-- This is the optional update URL for the app, if the files here get updated the app will auto update--&gt;
      &lt;UpdateURL&gt;http://minimal.jwrapper.com/&lt;/UpdateURL&gt;
  
  
  
      &lt;!-- Here's where you specify your Windows 32 bit JRE, note that you can use a 32 bit JRE on 64 bit Windows --&gt;
      &lt;Windows32JRE&gt;../windows/jre1.6.0_16&lt;/Windows32JRE&gt;
      &lt;Windows64JRE&gt;../windows/jre1.6.0_16&lt;/Windows64JRE&gt;
      &lt;Linux32JRE&gt;../linux/jre1.6.0_16&lt;/Linux32JRE&gt;
      &lt;Linux64JRE&gt;../linuxx64/jre1.6.0_16&lt;/Linux64JRE&gt;
  
      &lt;!-- Here's where you can add JAR files or whatever else your app needs to run --&gt;
      &lt;File classpath='yes'&gt;lib/*.jar&lt;/File&gt;
      &lt;File classpath='no' path='translations.properties'&gt;resources/translation.properties&lt;/File&gt;
  
  &lt;/JWrapper&gt;
  </code></pre>