void checkIfContainsFileWithSubstring(String substr) {
    for (final File dir : dirs) {
      File[] files = dir.listFiles();
      for (final File file : files) {
        if (file.getAbsolutePath().contains(substr)) {
          fail("file \"" + file.getAbsolutePath() + "\" still exists");
        }
      }
    }
  }
Testing methods for SimpleDiskRegion.java api's

@since GemFire 5.1
geode-core/src/integrationTest/java/org/apache/geode/internal/cache/SimpleDiskRegionJUnitTest.java