title: Gradle Build Failure Could not open proj class cache for build file
body: <pre><code>FAILURE: Build failed with an exception.
  
  * What went wrong:
  A problem occurred configuring root project 'oscar'.
  &gt; Could not open proj class cache for build file '/Users/prakashv/dev/workspace/oscar-api/build.gradle' (/Users/prakashv/.gradle/caches/2.6/scripts/build_7o20dvaacd2xu3ci3o56uhd4f/proj).
     &gt; Timeout waiting to lock proj class cache for build file '/Users/prakashv/dev/workspace/oscar-api/build.gradle' (/Users/prakashv/.gradle/caches/2.6/scripts/build_7o20dvaacd2xu3ci3o56uhd4f/proj). It is currently in use by another Gradle instance.
       Owner PID: unknown
       Our PID: 47991
       Owner Operation: unknown
       Our operation: Initialize cache
       Lock file: /Users/prakashv/.gradle/caches/2.6/scripts/build_7o20dvaacd2xu3ci3o56uhd4f/proj/cache.properties.lock
  
  * Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
  </code></pre>
  
  <p>Any idea what the problem could be ?
  I am using gradle 2.6 and Java 1.8.0_60</p>