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/*
* Copyright (c) 2007-present, Stephen Colebourne & Michael Nascimento Santos
*
* All rights reserved.
*
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* modification, are permitted provided that the following conditions are met:
*
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* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
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*
* * Neither the name of JSR-310 nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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package org.threeten.bp.temporal;
import org.threeten.bp.DateTimeException;
/**
* Strategy for adjusting a temporal object.
*
* Adjusters are a key tool for modifying temporal objects.
* They exist to externalize the process of adjustment, permitting different
* approaches, as per the strategy design pattern.
* Examples might be an adjuster that sets the date avoiding weekends, or one that
* sets the date to the last day of the month.
*
* There are two equivalent ways of using a {@code TemporalAdjuster}.
* The first is to invoke the method on this interface directly.
* The second is to use {@link Temporal#with(TemporalAdjuster)}:
*
* // these two lines are equivalent, but the second approach is recommended
* temporal = thisAdjuster.adjustInto(temporal);
* temporal = temporal.with(thisAdjuster);
*
* It is recommended to use the second approach, {@code with(TemporalAdjuster)},
* as it is a lot clearer to read in code.
*
* See {@link TemporalAdjusters} for a standard set of adjusters, including finding the
* last day of the month.
* Adjusters may also be defined by applications.
*
*
Specification for implementors
* This interface places no restrictions on the mutability of implementations,
* however immutability is strongly recommended.
*/
public interface TemporalAdjuster {
/**
* Adjusts the specified temporal object.
*
* This adjusts the specified temporal object using the logic
* encapsulated in the implementing class.
* Examples might be an adjuster that sets the date avoiding weekends, or one that
* sets the date to the last day of the month.
*
* There are two equivalent ways of using this method.
* The first is to invoke this method directly.
* The second is to use {@link Temporal#with(TemporalAdjuster)}:
*
* // these two lines are equivalent, but the second approach is recommended
* temporal = thisAdjuster.adjustInto(temporal);
* temporal = temporal.with(thisAdjuster);
*
* It is recommended to use the second approach, {@code with(TemporalAdjuster)},
* as it is a lot clearer to read in code.
*
* Specification for implementors
* The implementation must take the input object and adjust it.
* The implementation defines the logic of the adjustment and is responsible for
* documenting that logic. It may use any method on {@code Temporal} to
* query the temporal object and perform the adjustment.
* The returned object must have the same observable type as the input object
*
* The input object must not be altered.
* Instead, an adjusted copy of the original must be returned.
* This provides equivalent, safe behavior for immutable and mutable temporal objects.
*
* The input temporal object may be in a calendar system other than ISO.
* Implementations may choose to document compatibility with other calendar systems,
* or reject non-ISO temporal objects by {@link TemporalQueries#chronology() querying the chronology}.
*
* This method may be called from multiple threads in parallel.
* It must be thread-safe when invoked.
*
* @param temporal the temporal object to adjust, not null
* @return an object of the same observable type with the adjustment made, not null
* @throws DateTimeException if unable to make the adjustment
* @throws ArithmeticException if numeric overflow occurs
*/
Temporal adjustInto(Temporal temporal);
}