title: FAILURE: Build failed with an exception due to Could not download artifact when building RxJava
body: <p>What might be the reason for the build of RxJava project failing with the following exception?</p>
  
  <pre><code>jacek:~/oss/RxJava
  $ ./gradlew build -x test
  ...
  :rxjava-contrib:rxjava-android:compileJava
  Download http://repo1.maven.org/maven2/xerces/xmlParserAPIs/2.6.2/xmlParserAPIs-2.6.2.pom
  Download http://repo1.maven.org/maven2/xerces/xmlParserAPIs/2.6.2/xmlParserAPIs-2.6.2.jar
  
  FAILURE: Build failed with an exception.
  
  * What went wrong:
  Could not resolve all dependencies for configuration ':rxjava-contrib:rxjava-android:provided'.
  &gt; Could not download artifact 'org.apache.maven:maven-error-diagnostics:2.2.1@jar'
     &gt; Artifact 'org.apache.maven:maven-error-diagnostics:2.2.1@jar' not found.
  
  * Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
  
  BUILD FAILED
  
  Total time: 48.057 secs
  </code></pre>