/**
   * Test the feature of clearing a JEReplicaDB used by a replication server. The clear feature is
   * used when a replication server receives a request to reset the generationId of a given domain.
   */
  @Test
  public void testClear() throws Exception {
    ReplicationServer replicationServer = null;
    JEReplicaDB replicaDB = null;
    try {
      TestCaseUtils.startServer();
      replicationServer = configureReplicationServer(100, 5000);
      replicaDB = newReplicaDB(replicationServer);

      CSN[] csns = generateCSNs(1, 0, 3);

      // Add the changes and check they are here
      replicaDB.add(new DeleteMsg(TEST_ROOT_DN, csns[0], "uid"));
      replicaDB.add(new DeleteMsg(TEST_ROOT_DN, csns[1], "uid"));
      replicaDB.add(new DeleteMsg(TEST_ROOT_DN, csns[2], "uid"));

      assertEquals(csns[0], replicaDB.getOldestCSN());
      assertEquals(csns[2], replicaDB.getNewestCSN());

      // Clear DB and check it is cleared.
      replicaDB.clear();

      assertEquals(null, replicaDB.getOldestCSN());
      assertEquals(null, replicaDB.getNewestCSN());
    } finally {
      shutdown(replicaDB);
      remove(replicationServer);
    }
  }
  @Test
  public void testTrim() throws Exception {
    ReplicationServer replicationServer = null;
    JEReplicaDB replicaDB = null;
    try {
      TestCaseUtils.startServer();
      replicationServer = configureReplicationServer(100, 5000);
      replicaDB = newReplicaDB(replicationServer);

      CSN[] csns = generateCSNs(1, 0, 5);

      replicaDB.add(new DeleteMsg(TEST_ROOT_DN, csns[0], "uid"));
      replicaDB.add(new DeleteMsg(TEST_ROOT_DN, csns[1], "uid"));
      replicaDB.add(new DeleteMsg(TEST_ROOT_DN, csns[2], "uid"));
      DeleteMsg update4 = new DeleteMsg(TEST_ROOT_DN, csns[3], "uid");

      // --
      // Iterator tests with changes persisted
      assertFoundInOrder(replicaDB, csns[0], csns[1], csns[2]);
      assertNotFound(replicaDB, csns[4], AFTER_MATCHING_KEY);

      assertEquals(replicaDB.getOldestCSN(), csns[0]);
      assertEquals(replicaDB.getNewestCSN(), csns[2]);

      // --
      // Cursor tests with changes persisted
      replicaDB.add(update4);

      assertFoundInOrder(replicaDB, csns[0], csns[1], csns[2], csns[3]);
      // Test cursor from existing CSN
      assertFoundInOrder(replicaDB, csns[2], csns[3]);
      assertFoundInOrder(replicaDB, csns[3]);
      assertNotFound(replicaDB, csns[4], AFTER_MATCHING_KEY);

      replicaDB.purgeUpTo(new CSN(Long.MAX_VALUE, 0, 0));

      int count = 0;
      boolean purgeSucceeded = false;
      final CSN expectedNewestCSN = csns[3];
      do {
        Thread.sleep(10);

        final CSN oldestCSN = replicaDB.getOldestCSN();
        final CSN newestCSN = replicaDB.getNewestCSN();
        purgeSucceeded = oldestCSN.equals(expectedNewestCSN) && newestCSN.equals(expectedNewestCSN);
        count++;
      } while (!purgeSucceeded && count < 100);
      assertTrue(purgeSucceeded);
    } finally {
      shutdown(replicaDB);
      remove(replicationServer);
    }
  }
  private void testGetOldestNewestCSNs(final int max, final int counterWindow) throws Exception {
    String tn = "testDBCount(" + max + "," + counterWindow + ")";
    debugInfo(tn, "Starting test");

    File testRoot = null;
    ReplicationServer replicationServer = null;
    ReplicationDbEnv dbEnv = null;
    JEReplicaDB replicaDB = null;
    try {
      TestCaseUtils.startServer();
      replicationServer = configureReplicationServer(100000, 10);

      testRoot = createCleanDir();
      dbEnv = new ReplicationDbEnv(testRoot.getPath(), replicationServer);
      replicaDB = new JEReplicaDB(1, TEST_ROOT_DN, replicationServer, dbEnv);
      replicaDB.setCounterRecordWindowSize(counterWindow);

      // Populate the db with 'max' msg
      int mySeqnum = 1;
      CSN csns[] = new CSN[2 * (max + 1)];
      long now = System.currentTimeMillis();
      for (int i = 1; i <= max; i++) {
        csns[i] = new CSN(now + i, mySeqnum, 1);
        replicaDB.add(new DeleteMsg(TEST_ROOT_DN, csns[i], "uid"));
        mySeqnum += 2;
      }

      assertEquals(replicaDB.getOldestCSN(), csns[1], "Wrong oldest CSN");
      assertEquals(replicaDB.getNewestCSN(), csns[max], "Wrong newest CSN");

      // Now we want to test that after closing and reopening the db, the
      // counting algo is well reinitialized and when new messages are added
      // the new counter are correctly generated.
      debugInfo(tn, "SHUTDOWN replicaDB and recreate");
      replicaDB.shutdown();

      replicaDB = new JEReplicaDB(1, TEST_ROOT_DN, replicationServer, dbEnv);
      replicaDB.setCounterRecordWindowSize(counterWindow);

      assertEquals(replicaDB.getOldestCSN(), csns[1], "Wrong oldest CSN");
      assertEquals(replicaDB.getNewestCSN(), csns[max], "Wrong newest CSN");

      // Populate the db with 'max' msg
      for (int i = max + 1; i <= 2 * max; i++) {
        csns[i] = new CSN(now + i, mySeqnum, 1);
        replicaDB.add(new DeleteMsg(TEST_ROOT_DN, csns[i], "uid"));
        mySeqnum += 2;
      }

      assertEquals(replicaDB.getOldestCSN(), csns[1], "Wrong oldest CSN");
      assertEquals(replicaDB.getNewestCSN(), csns[2 * max], "Wrong newest CSN");

      replicaDB.purgeUpTo(new CSN(Long.MAX_VALUE, 0, 0));

      String testcase = "AFTER PURGE (oldest, newest)=";
      debugInfo(tn, testcase + replicaDB.getOldestCSN() + replicaDB.getNewestCSN());
      assertEquals(replicaDB.getNewestCSN(), csns[2 * max], "Newest=");

      // Clear ...
      debugInfo(tn, "clear:");
      replicaDB.clear();

      // Check the db is cleared.
      assertEquals(null, replicaDB.getOldestCSN());
      assertEquals(null, replicaDB.getNewestCSN());
      debugInfo(tn, "Success");
    } finally {
      shutdown(replicaDB);
      if (dbEnv != null) {
        dbEnv.shutdown();
      }
      remove(replicationServer);
      TestCaseUtils.deleteDirectory(testRoot);
    }
  }