com.github.triceo.robozonky.notifications.email.BalanceTracker Maven / Gradle / Ivy
/*
* Copyright 2017 Lukáš Petrovický
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.github.triceo.robozonky.notifications.email;
import java.util.Optional;
import java.util.OptionalInt;
import com.github.triceo.robozonky.internal.api.State;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
enum BalanceTracker {
INSTANCE; // fast thread-safe singleton
private static final Logger LOGGER = LoggerFactory.getLogger(BalanceTracker.class);
private static final State.ClassSpecificState STATE = State.INSTANCE.forClass(BalanceTracker.class);
static final String BALANCE_KEY = "lastKnownBalance";
public OptionalInt getLastKnownBalance() {
final Optional lastKnownBalance = BalanceTracker.STATE.getValue(BalanceTracker.BALANCE_KEY);
if (!lastKnownBalance.isPresent()) {
BalanceTracker.LOGGER.debug("No last known balance.");
return OptionalInt.empty();
} else try {
return OptionalInt.of(Integer.parseInt(lastKnownBalance.get()));
} catch (final Exception ex) {
BalanceTracker.LOGGER.debug("Failed initializing balance.", ex);
this.reset();
return OptionalInt.empty();
}
}
public void setLastKnownBalance(final int newBalance) {
BalanceTracker.STATE.setValue(BalanceTracker.BALANCE_KEY, String.valueOf(newBalance));
}
boolean reset() {
return BalanceTracker.STATE.reset();
}
}