@Test
  public void testPuttingBackChunksAfterFlushing() throws IOException {
    byte[] row = Bytes.toBytes("testrow");
    byte[] fam = Bytes.toBytes("testfamily");
    byte[] qf1 = Bytes.toBytes("testqualifier1");
    byte[] qf2 = Bytes.toBytes("testqualifier2");
    byte[] qf3 = Bytes.toBytes("testqualifier3");
    byte[] qf4 = Bytes.toBytes("testqualifier4");
    byte[] qf5 = Bytes.toBytes("testqualifier5");
    byte[] val = Bytes.toBytes("testval");

    // Setting up memstore
    memstore.add(new KeyValue(row, fam, qf1, val), null);
    memstore.add(new KeyValue(row, fam, qf2, val), null);
    memstore.add(new KeyValue(row, fam, qf3, val), null);

    // Creating a snapshot
    MemStoreSnapshot snapshot = memstore.snapshot();
    assertEquals(3, memstore.getSnapshot().getCellsCount());

    // Adding value to "new" memstore
    assertEquals(0, memstore.getActive().getCellsCount());
    memstore.add(new KeyValue(row, fam, qf4, val), null);
    memstore.add(new KeyValue(row, fam, qf5, val), null);
    assertEquals(2, memstore.getActive().getCellsCount());
    // close the scanners
    for (KeyValueScanner scanner : snapshot.getScanners()) {
      scanner.close();
    }
    memstore.clearSnapshot(snapshot.getId());

    int chunkCount = chunkCreator.getPoolSize();
    assertTrue(chunkCount > 0);

  }
Tests that the timeOfOldestEdit is updated correctly for the various edit operations in
memstore.
hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCompactingMemStore.java