/*
* -----------------------------------------------------------------------
* Copyright © 2013-2015 Meno Hochschild, <http://www.menodata.de/>
* -----------------------------------------------------------------------
* This file (OverflowUnit.java) is part of project Time4J.
*
* Time4J 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 2.1 of the License, or
* (at your option) any later version.
*
* Time4J 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with Time4J. If not, see <http://www.gnu.org/licenses/>.
* -----------------------------------------------------------------------
*/
package net.time4j;
import net.time4j.engine.BasicUnit;
import net.time4j.engine.ChronoEntity;
import net.time4j.engine.Chronology;
import net.time4j.engine.UnitRule;
import java.io.Serializable;
/**
* <p>Specialized calendar unit for handling day overflow. </p>
*
* @author Meno Hochschild
* @doctags.concurrency {immutable}
*/
final class OverflowUnit
extends BasicUnit
implements IsoDateUnit, Serializable {
//~ Statische Felder/Initialisierungen --------------------------------
/**
* Standard policy which resets the invalid day of month to the previous
* valid one.
*/
static final int POLICY_PREVIOUS_VALID_DATE = 0;
/**
* Resolves the invalid day of month to the next valid one.
*/
static final int POLICY_NEXT_VALID_DATE = 1;
/**
* Always moves the day of month to the last day of month even if valid.
*/
static final int POLICY_END_OF_MONTH = 2;
/**
* Any carry-over will be transferred to the next month.
*/
static final int POLICY_CARRY_OVER = 3;
/**
* This policy causes an exception in case of day overflow.
*/
static final int POLICY_UNLESS_INVALID = 4;
/**
* Moves the day of month to the last day of month if the original date
* is the last day of month.
*
* @since 2.3
*/
static final int POLICY_KEEPING_LAST_DATE = 5;
private static final long serialVersionUID = 1988843503875912054L;
//~ Instanzvariablen ----------------------------------------------
/**
* @serial calendar unit
*/
private final CalendarUnit unit;
/**
* @serial day overflow policy
*/
private final int policy;
//~ Konstruktoren -------------------------------------------------
/**
* <p>Erzeugt eine neue Instanz. </p>
*
* @param unit calendar unit as delegate
* @param policy strategy for handling day overflow
*/
OverflowUnit(
CalendarUnit unit,
int policy
) {
super();
this.unit = unit;
this.policy = policy;
}
//~ Methoden ------------------------------------------------------
/**
* <p>Diese Einheit hat kein Symbol. </p>
*
* @return ASCII-null
*/
@Override
public char getSymbol() {
return '\u0000';
}
/**
* <p>Delegiert an die zugrundeliegende {@code CalendarUnit}. </p>
*
* @return estimated standard length
*/
@Override
public double getLength() {
return this.unit.getLength();
}
/**
* <p>Diese Einheit ist kalendarisch. </p>
*
* @return {@code true}
*/
@Override
public boolean isCalendrical() {
return true;
}
@Override
protected <T extends ChronoEntity<T>> UnitRule<T> derive(
Chronology<T> chronology
) {
if (chronology.isRegistered(PlainDate.CALENDAR_DATE)) {
return new CalendarUnit.Rule<>(this.unit, this.policy);
}
return null;
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
} else if (obj instanceof OverflowUnit) {
OverflowUnit that = (OverflowUnit) obj;
return (
(this.unit == that.unit)
&& (this.policy == that.policy)
);
} else {
return false;
}
}
@Override
public int hashCode() {
return 23 * this.unit.hashCode() + 37 * this.policy;
}
/**
* <p>Liefert eine Kombination aus Einheitenname und
* Überlaufstrategie. </p>
*
* @return String in format [{symbol}-{policy}]
*/
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(this.unit.getSymbol());
sb.append('-');
switch (this.policy) {
case POLICY_NEXT_VALID_DATE:
sb.append("NEXT_VALID_DATE");
break;
case POLICY_END_OF_MONTH:
sb.append("END_OF_MONTH");
break;
case POLICY_CARRY_OVER:
sb.append("CARRY_OVER");
break;
case POLICY_UNLESS_INVALID:
sb.append("UNLESS_INVALID");
break;
case POLICY_KEEPING_LAST_DATE:
sb.append("KEEPING_LAST_DATE");
break;
default:
sb.append("PREVIOUS_VALID_DATE");
}
return sb.toString();
}
/**
* <p>Liefert die interne Zeiteinheit. </p>
*
* @return delegate calendar unit
*/
CalendarUnit getCalendarUnit() {
return this.unit;
}
}