code: @Override
      @FFDCIgnore(SecurityException.class)
      public ExtendedConfiguration[] listConfigurations(String filterString) throws InvalidSyntaxException {
          if (filterString == null)
              filterString = "(" + Constants.SERVICE_PID + "=*)"; //$NON-NLS-1$ //$NON-NLS-2$
  
          try {
              this.caFactory.checkConfigurationPermission();
          } catch (SecurityException e) {
              filterString = "(&(" + ConfigurationAdmin.SERVICE_BUNDLELOCATION + "=" + bundle.getLocation() + ")" + filterString + ")";
          }
          return caFactory.getConfigurationStore().listConfigurations(FrameworkUtil.createFilter(filterString));
      }
docs: /*
  (non-Javadoc)
  
  @see
  org.osgi.service.cm.ConfigurationAdmin#listConfigurations(java.lang.String)