private void trySplitAndEnsureItIsSuccess(final TableName tableName) throws Exception {
    // get the original table region count
    List<RegionInfo> regions = admin.getRegions(tableName);
    int originalCount = regions.size();

    // split the table and wait until region count increases
    admin.split(tableName, Bytes.toBytes(3));
    TEST_UTIL.waitFor(30000, new ExplainingPredicate<Exception>() {

      @Override
      public boolean evaluate() throws Exception {
        return admin.getRegions(tableName).size() > originalCount;
      }

      @Override
      public String explainFailure() throws Exception {
        return "Split has not finished yet";
      }
    });
  }
Method to enable split for the passed table and validate this modification.
@param tableName name of the table
hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestSplitOrMergeAtTableLevel.java