title: Java: java.lang.NoClassDefFoundError: org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager
body: <p>I created a webservice using servlet and Tomcat 6.0.
  I created a java project in eclipse to call that webservice using HTTP.<br>
  I added the following jar files<br>
  1. httpcore-4.0<br>
  2. httpclient-4.0<br>
  but while running the project im getting the following error.    </p>
  
  <pre><code>Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory
  at org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager.&lt;init&gt;(ThreadSafeClientConnManager.java:75)
  at WSCall.HttpUtilities.GetServerResponse(HttpUtilities.java:52)
  at WSCall.ServiceCall.main(ServiceCall.java:16)
  Caused by: java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory
  at java.net.URLClassLoader$1.run(Unknown Source)
  at java.security.AccessController.doPrivileged(Native Method)
  at java.net.URLClassLoader.findClass(Unknown Source)
  at java.lang.ClassLoader.loadClass(Unknown Source)
  at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
  at java.lang.ClassLoader.loadClass(Unknown Source)
  ... 3 more    
  </code></pre>
  
  <p>Please help me to find the solution.</p>