private void verifyRegionOnPrimaryRS(int expectedNum) throws IOException {
    lastRegionOnPrimaryRSCount = getNumRegionisOnPrimaryRS();
    assertEquals(
      "Only " + expectedNum + " of user regions running " + "on the primary region server",
      expectedNum, lastRegionOnPrimaryRSCount);
  }
Verify the number of user regions is assigned to the primary region server based on the plan is
expected
@param expectedNum the expected number of assigned regions
hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestRegionPlacement.java