code: public boolean isAllowedPackage(String packageName)
     {
  
        // No packages in set? Accept all packages.
        if (packageSet.isEmpty())
        {
           return true;
        }
  
        // check all valid packages
        for (String validPackage : packageSet)
        {
           // accept if package is a sub-package of a valid package
           if (packageName.startsWith(validPackage))
           {
              return true;
           }
        }
  
        // package noch accepted
        return false;
  
     }
docs: <p>
  Checks whether the supplied packages matches the filter.
  </p>
  <p>
  The method returns <code>true</code> if one of the following checks succeed:
  </p>
  <ul>
  <li>The supplied package is one of the packages specified in the filter condition.</li>
  <li>The supplied package is a sub-package of one of the packages specified in the filter condition.</li>
  </ul>
  
  @param packageName A package name
  @return <code>true</code> if the filter matches