org.openbase.jul.schedule.TimeoutSplitter Maven / Gradle / Ivy
package org.openbase.jul.schedule;
/*-
* #%L
* JUL Schedule
* %%
* Copyright (C) 2015 - 2022 openbase.org
* %%
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Lesser Public License for more details.
*
* You should have received a copy of the GNU General Lesser Public
* License along with this program. If not, see
* .
* #L%
*/
import org.openbase.jul.exception.TimeoutException;
import org.openbase.jul.pattern.provider.Provider;
import org.openbase.jul.pattern.provider.StableProvider;
import org.openbase.jul.pattern.provider.StringProvider;
import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;
/**
* Class can be use to split a given timeout between multiple wait or get calls within a method,
* while it makes sure that the method does not block longer in total then the given timeout.
*
* Usage Example:
* {@code public void waitForABC(final long timeout, final TimeUnit timeUnit) throws CouldNotPerformException, InterruptedException {
* final TimeoutSplitter timeSplit = new TimeoutSplitter(timeout, timeUnit);
*
* waitForA(timeSplit.getTime(), TimeUnit.MILLISECONDS);
* waitForB(timeSplit.getTime(), TimeUnit.MILLISECONDS);
* C.wait(timeSplit.getTime());
* }}
*/
public class TimeoutSplitter {
public static final TimeUnit DEFAULT_TIME_UNIT = TimeUnit.MILLISECONDS;
/**
* In milliseconds
*/
private final long timestamp;
/**
* In milliseconds
*/
private final long timeout;
/**
* @param timeout the total max time to wait.
* @param timeUnit the time unit of the given {@code timeout}.
*/
public TimeoutSplitter(final long timeout, final TimeUnit timeUnit) {
this.timestamp = System.currentTimeMillis();
this.timeout = timeUnit.toMillis(timeout);
}
/**
* The time left.
*
* @return the time in milliseconds.
*
* @throws TimeoutException is thrown when the timeout is reached.
*/
public long getTime(StableProvider timeoutMessage) throws TimeoutException {
final long time = timeout - (System.currentTimeMillis() - timestamp);
if (time <= 0) {
throw new TimeoutException(timeoutMessage.get());
}
return time;
}
/**
* The time left.
*
* @return the time in milliseconds.
*
* @throws TimeoutException is thrown when the timeout is reached.
*/
public long getTime() throws TimeoutException {
final long time = timeout - (System.currentTimeMillis() - timestamp);
if (time <= 0) {
throw new TimeoutException();
}
return time;
}
/**
* This method returns time unit of the {@code getTime()} method returned value, which is milliseconds by default.
* For details checkout {@code TimeoutSplitter.DEFAULT_TIME_UNIT}.
*
* @return the millisecond time unit.
*/
public TimeUnit getTimeUnit() {
return DEFAULT_TIME_UNIT;
}
/**
* Returns the timestamp of when this object was created.
* @return the timestamp in ms.
*/
public long getTimestamp() {
return timestamp;
}
}