@Test
  public void asyncBackups_whenForceSyncEnabled() {
    setup(true);

    // when forceSync is enabled, then async should always be 0
    assertEquals(0, backupHandler.asyncBackups(0, 0, FORCE_SYNC_ENABLED));
    assertEquals(0, backupHandler.asyncBackups(0, 1, FORCE_SYNC_ENABLED));
    assertEquals(0, backupHandler.asyncBackups(2, 0, FORCE_SYNC_ENABLED));
    assertEquals(0, backupHandler.asyncBackups(2, 1, FORCE_SYNC_ENABLED));

    // see what happens when we reach maximum number of backups
    assertEquals(0, backupHandler.asyncBackups(0, BACKUPS + 1, FORCE_SYNC_ENABLED));
  }
  @Test
  public void asyncBackups_whenForceSyncDisabled() {
    setup(BACKPRESSURE_ENABLED);

    // when forceSync disabled, only the async matters
    assertEquals(0, backupHandler.asyncBackups(0, 0, FORCE_SYNC_DISABLED));
    assertEquals(1, backupHandler.asyncBackups(0, 1, FORCE_SYNC_DISABLED));
    assertEquals(0, backupHandler.asyncBackups(2, 0, FORCE_SYNC_DISABLED));
    assertEquals(1, backupHandler.asyncBackups(2, 1, FORCE_SYNC_DISABLED));

    // see what happens when we reach maximum number of backups
    assertEquals(BACKUPS, backupHandler.asyncBackups(0, BACKUPS + 1, FORCE_SYNC_DISABLED));
  }
  @Test
  public void syncBackups_whenForceSyncDisabled() {
    setup(BACKPRESSURE_ENABLED);

    // when force-sync disabled, we only look at the sync backups
    assertEquals(0, backupHandler.syncBackups(0, 0, FORCE_SYNC_DISABLED));
    assertEquals(1, backupHandler.syncBackups(1, 0, FORCE_SYNC_DISABLED));
    assertEquals(0, backupHandler.syncBackups(0, 0, FORCE_SYNC_DISABLED));
    assertEquals(1, backupHandler.syncBackups(1, 1, FORCE_SYNC_DISABLED));

    // checking to see what happens when we are at or above the maximum number of backups
    assertEquals(BACKUPS, backupHandler.syncBackups(BACKUPS, 0, FORCE_SYNC_DISABLED));
    assertEquals(BACKUPS, backupHandler.syncBackups(BACKUPS + 1, 0, FORCE_SYNC_DISABLED));
  }
  @Test
  public void syncBackups_whenForceSyncEnabled() {
    setup(BACKPRESSURE_ENABLED);

    // when force sync enabled, we sum tot sync and asyncs
    assertEquals(0, backupHandler.syncBackups(0, 0, FORCE_SYNC_ENABLED));
    assertEquals(1, backupHandler.syncBackups(1, 0, FORCE_SYNC_ENABLED));
    assertEquals(0, backupHandler.syncBackups(0, 0, FORCE_SYNC_ENABLED));
    assertEquals(3, backupHandler.syncBackups(1, 2, FORCE_SYNC_ENABLED));

    // checking to see what happens when we are at or above the maximum number of backups
    assertEquals(BACKUPS, backupHandler.syncBackups(BACKUPS, 0, FORCE_SYNC_ENABLED));
    assertEquals(BACKUPS, backupHandler.syncBackups(BACKUPS + 1, 0, FORCE_SYNC_ENABLED));
    assertEquals(BACKUPS, backupHandler.syncBackups(BACKUPS, 1, FORCE_SYNC_ENABLED));
  }
  @Test(expected = IllegalArgumentException.class)
  public void backup_whenTooLargeSumOfSyncAndAsync() throws Exception {
    setup(BACKPRESSURE_ENABLED);

    BackupAwareOperation op = makeOperation(1, MAX_BACKUP_COUNT);
    backupHandler.backup(op);
  }
  @Test(expected = IllegalArgumentException.class)
  public void backup_whenNegativeAsyncBackupCount() throws Exception {
    setup(BACKPRESSURE_ENABLED);

    BackupAwareOperation op = makeOperation(0, -1);
    backupHandler.backup(op);
  }
  private void assertBackup(final int syncBackups, final int asyncBackups, int expectedResult)
      throws Exception {
    final DummyBackupAwareOperation backupAwareOp = makeOperation(syncBackups, asyncBackups);

    int result = backupHandler.backup(backupAwareOp);

    assertEquals(expectedResult, result);
    assertTrueEventually(
        new AssertTask() {
          @Override
          public void run() throws Exception {
            Integer completed = backupCompletedMap.get(backupAwareOp.backupKey);
            if (completed == null) {
              completed = 0;
            }
            int totalBackups = min(BACKUPS, syncBackups + asyncBackups);
            assertEquals(new Integer(totalBackups), completed);
          }
        });
  }