/*
* Copyright 2001-2007 Stephen Colebourne
*
* 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 org.joda.time.field;
import org.joda.time.Chronology;
import org.joda.time.DateTimeField;
/**
* Converts a strict DateTimeField into a lenient one. By being lenient, the
* set method accepts out of bounds values, performing an addition instead.
* <p>
* LenientDateTimeField is thread-safe and immutable.
*
* @author Brian S O'Neill
* @see org.joda.time.chrono.LenientChronology
* @see StrictDateTimeField
* @since 1.0
*/
public class LenientDateTimeField extends DelegatedDateTimeField {
private static final long serialVersionUID = 8714085824173290599L;
private final Chronology iBase;
/**
* Returns a lenient version of the given field. If it is already lenient,
* then it is returned as-is. Otherwise, a new LenientDateTimeField is
* returned.
*/
public static DateTimeField getInstance(DateTimeField field, Chronology base) {
if (field == null) {
return null;
}
if (field instanceof StrictDateTimeField) {
field = ((StrictDateTimeField)field).getWrappedField();
}
if (field.isLenient()) {
return field;
}
return new LenientDateTimeField(field, base);
}
protected LenientDateTimeField(DateTimeField field, Chronology base) {
super(field);
iBase = base;
}
public final boolean isLenient() {
return true;
}
/**
* Set values which may be out of bounds by adding the difference between
* the new value and the current value.
*/
public long set(long instant, int value) {
// lenient needs to handle time zone chronologies
// so we do the calculation using local milliseconds
long localInstant = iBase.getZone().convertUTCToLocal(instant);
long difference = FieldUtils.safeSubtract(value, get(instant));
localInstant = getType().getField(iBase.withUTC()).add(localInstant, difference);
return iBase.getZone().convertLocalToUTC(localInstant, false, instant);
}
}