net.time4j.engine

Class AbstractMetric<U extends ChronoUnit,P extends AbstractDuration<U>>

java.lang.Object

net.time4j.engine.AbstractMetric<U,P>

Type Parameters:

U - generic type of time unit (ChronoUnit)

P - generic type of duration result

All Implemented Interfaces:

Comparator<U>, TimeMetric<U,P>

public abstract class AbstractMetric<U extends ChronoUnit,P extends AbstractDuration<U>>
extends Object
implements TimeMetric<U,P>, Comparator<U>

Represents a metric suitable for the default algorithm of Time4J.

If the starting time point is after the end time point then a duration computed with this metric will be negative. In this case the metric defined here will first toggle the time points to be compared and then compare all elements in the order of ascending precision. Elements which differ less than a full unit will cause an amount of 0 in related duration item. Convertible units will be consolidated in one step. Finally the representation of the duration will be normalized such that small units will be converted to larger units if possible.

Author:

Meno Hochschild

See Also:

AbstractDuration

Method Summary

Modifier and Type	Method and Description
<T extends TimePoint<? super U,T>> P	between(T start, T end) Computes the temporal distance between two time points.
int	compare(U u1, U u2) Compares time units by their length in descending order.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Method Detail

compare

public int compare(U u1,
                   U u2)

Compares time units by their length in descending order.

Specified by:

compare in interface Comparator<U extends ChronoUnit>

Parameters:

u1 - first time unit

u2 - second time unit

Returns:

negative, zero or positive if u1 is greater, equal to or smaller than u2

between

public <T extends TimePoint<? super U,T>> P between(T start,
                                                    T end)

Description copied from interface: TimeMetric

Computes the temporal distance between two time points.

Important note: This method might not work in Java 6 under some circumstances. In case of any problem users can use the equivalent method until() defined in the class TimePoint.

Specified by:

between in interface TimeMetric<U extends ChronoUnit,P extends AbstractDuration<U>>

Type Parameters:

T - generic type of time point

Parameters:

start - first time point

end - second time point

Returns:

calculated time span between given time points, will be negative if start is after end

See Also:

TimePoint.until(TimePoint, TimeMetric)