/* Test mutable and persistent configurations. */
  @Test
  public void testPersistentAndMutableConfigs() throws Exception {

    final String dbName = "foo";

    EnvironmentConfig envConfig = TestUtils.initEnvConfig();
    envConfig.setAllowCreate(true);
    envConfig.setTransactional(true);
    env = create(envHome, envConfig);

    DbConfigManager configMgr = DbInternal.getEnvironmentImpl(env).getConfigManager();
    int defaultNodeMaxEntries = configMgr.getInt(EnvironmentParams.NODE_MAX);
    int defaultNodeDupTreeMaxEntries = configMgr.getInt(EnvironmentParams.NODE_MAX_DUPTREE);

    /* Check the default node max entries setting. */
    assertEquals(defaultNodeMaxEntries, 128);
    assertEquals(defaultNodeDupTreeMaxEntries, 128);

    DatabaseConfig dbConfig = new DatabaseConfig();
    dbConfig.setAllowCreate(true);
    dbConfig.setTransactional(true);

    /* Do updates on each persistent and mutable config. */

    /* Check whether BtreeComparator setting is persisted. */
    dbConfig.setOverrideBtreeComparator(true);
    dbConfig.setBtreeComparator(TestComparator.class);
    DatabaseConfig newConfig = setAndGetDbConfig(env, dbConfig, dbName);
    assertTrue(newConfig.getBtreeComparator() instanceof TestComparator);

    /* Check whether DuplicateComparator setting is persisted. */
    dbConfig.setOverrideDuplicateComparator(true);
    dbConfig.setDuplicateComparator(new TestSerialComparator());
    newConfig = setAndGetDbConfig(env, dbConfig, dbName);
    assertTrue(newConfig.getDuplicateComparator() instanceof TestSerialComparator);

    /* Check whether KeyPrefixing setting is persisted. */
    dbConfig.setKeyPrefixing(true);
    newConfig = setAndGetDbConfig(env, dbConfig, dbName);
    assertTrue(newConfig.getKeyPrefixing());

    /* Check whether NodeMaxEntries setting is persisted. */
    dbConfig.setNodeMaxEntries(512);
    newConfig = setAndGetDbConfig(env, dbConfig, dbName);
    assertTrue(newConfig.getNodeMaxEntries() == 512);

    close(env);
  }