/* * Copyright 2001-2005 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 java.io.Serializable; import java.util.Locale; import org.joda.time.Chronology; import org.joda.time.DateTimeField; import org.joda.time.DateTimeFieldType; import org.joda.time.DateTimeUtils; import org.joda.time.DurationField; import org.joda.time.Interval; import org.joda.time.ReadableInstant; import org.joda.time.ReadablePartial; /** * AbstractReadableInstantFieldProperty is a base class for binding a * ReadableInstant to a DateTimeField. *
* It allows the date and time manipulation code to be field based yet * still easy to use. *
* AbstractReadableInstantFieldProperty itself is thread-safe and immutable, * but the ReadableInstant being operated on may be mutable and not * thread-safe. * * @author Stephen Colebourne * @author Brian S O'Neill * @author Mike Schrag * @since 1.0 */ public abstract class AbstractReadableInstantFieldProperty implements Serializable { /** Serialization version. */ private static final long serialVersionUID = 1971226328211649661L; /** * Constructor. */ public AbstractReadableInstantFieldProperty() { super(); } //----------------------------------------------------------------------- /** * Gets the field being used. * * @return the field */ public abstract DateTimeField getField(); /** * Gets the field type being used. * * @return the field type */ public DateTimeFieldType getFieldType() { return getField().getType(); } /** * Gets the name of the field. * * @return the field name */ public String getName() { return getField().getName(); } /** * Gets the milliseconds of the datetime that this property is linked to. * * @return the milliseconds */ protected abstract long getMillis(); /** * Gets the chronology of the datetime that this property is linked to. *
* This implementation throws UnsupportedOperationException, and must be * implemented by subclasses to enable the equals() and hashCode() methods. * * @return the chronology * @since 1.4 */ protected Chronology getChronology() { throw new UnsupportedOperationException( "The method getChronology() was added in v1.4 and needs " + "to be implemented by subclasses of AbstractReadableInstantFieldProperty"); } //----------------------------------------------------------------------- /** * Gets the value of this property from the instant. *
* For example, the following two lines of code are equivalent: *
* datetime.getDayOfMonth(); * datetime.dayOfMonth().get(); ** * @return the current value * @see DateTimeField#get */ public int get() { return getField().get(getMillis()); } /** * Gets the value of this property from the instant as a string. *
* This method returns the value converted to a String
* using Integer.toString
. This method does NOT return
* textual descriptions such as 'Monday' or 'January'.
* See {@link #getAsText()} and {@link #getAsShortText()} for those.
*
* @return the current value
* @see DateTimeField#get
* @since 1.1
*/
public String getAsString() {
return Integer.toString(get());
}
/**
* Gets the textual value of this property from the instant as a
* string in the default locale.
*
* This method returns the value converted to a String
* returning the appropriate textual description wherever possible.
* Thus, a day of week of 1 would return 'Monday' in English.
*
* @return the current text value
* @see DateTimeField#getAsText
*/
public String getAsText() {
return getAsText(null);
}
/**
* Gets the textual value of this property from the instant as a
* string in the specified locale.
*
* This method returns the value converted to a String
* returning the appropriate textual description wherever possible.
* Thus, a day of week of 1 would return 'Monday' in English.
*
* @param locale locale to use for selecting a text symbol, null means default
* @return the current text value
* @see DateTimeField#getAsText
*/
public String getAsText(Locale locale) {
return getField().getAsText(getMillis(), locale);
}
/**
* Gets the short textual value of this property from the instant as a
* string in the default locale.
*
* This method returns the value converted to a String
* returning the appropriate textual description wherever possible.
* Thus, a day of week of 1 would return 'Mon' in English.
*
* @return the current text value
* @see DateTimeField#getAsShortText
*/
public String getAsShortText() {
return getAsShortText(null);
}
/**
* Gets the short textual value of this property from the instant as a
* string in the specified locale.
*
* This method returns the value converted to a String
* returning the appropriate textual description wherever possible.
* Thus, a day of week of 1 would return 'Mon' in English.
*
* @param locale locale to use for selecting a text symbol, null means default
* @return the current text value
* @see DateTimeField#getAsShortText
*/
public String getAsShortText(Locale locale) {
return getField().getAsShortText(getMillis(), locale);
}
//-----------------------------------------------------------------------
/**
* Returns the difference between this field property instant and the one
* passed in, in the units of this field. The sign of the difference
* matches that of compareTo. In other words, this field property's instant
* is the minuend.
*
* @param instant the subtrahend, null means now
* @return the difference in the units of this field
* @see DateTimeField#getDifference
*/
public int getDifference(ReadableInstant instant) {
if (instant == null) {
return getField().getDifference(getMillis(), DateTimeUtils.currentTimeMillis());
}
return getField().getDifference(getMillis(), instant.getMillis());
}
/**
* Returns the difference between this field property instant and the one
* passed in, in the units of this field. The sign of the difference
* matches that of compareTo. In other words, this field property's instant
* is the minuend.
*
* @param instant the subtrahend, null means now
* @return the difference in the units of this field
* @see DateTimeField#getDifference
*/
public long getDifferenceAsLong(ReadableInstant instant) {
if (instant == null) {
return getField().getDifferenceAsLong(getMillis(), DateTimeUtils.currentTimeMillis());
}
return getField().getDifferenceAsLong(getMillis(), instant.getMillis());
}
//-----------------------------------------------------------------------
/**
* Returns the duration per unit value of this field. For example, if this
* field represents "hour of day", then the duration is an hour.
*
* @return the duration of this field, or UnsupportedDurationField
*/
public DurationField getDurationField() {
return getField().getDurationField();
}
/**
* Returns the range duration of this field. For example, if this field
* represents "hour of day", then the range duration is a day.
*
* @return the range duration of this field, or null if field has no range
*/
public DurationField getRangeDurationField() {
return getField().getRangeDurationField();
}
/**
* Gets whether this field is leap.
*
* @return true if a leap field
* @see DateTimeField#isLeap
*/
public boolean isLeap() {
return getField().isLeap(getMillis());
}
/**
* Gets the amount by which this field is leap.
*
* @return the amount by which the field is leap
* @see DateTimeField#getLeapAmount
*/
public int getLeapAmount() {
return getField().getLeapAmount(getMillis());
}
/**
* If this field were to leap, then it would be in units described by the
* returned duration. If this field doesn't ever leap, null is returned.
*/
public DurationField getLeapDurationField() {
return getField().getLeapDurationField();
}
//-----------------------------------------------------------------------
/**
* Gets the minimum value for the field ignoring the current time.
*
* @return the minimum value
* @see DateTimeField#getMinimumValue
*/
public int getMinimumValueOverall() {
return getField().getMinimumValue();
}
/**
* Gets the minimum value for the field.
*
* @return the minimum value
* @see DateTimeField#getMinimumValue
*/
public int getMinimumValue() {
return getField().getMinimumValue(getMillis());
}
/**
* Gets the maximum value for the field ignoring the current time.
*
* @return the maximum value
* @see DateTimeField#getMaximumValue
*/
public int getMaximumValueOverall() {
return getField().getMaximumValue();
}
/**
* Gets the maximum value for the field.
*
* @return the maximum value
* @see DateTimeField#getMaximumValue
*/
public int getMaximumValue() {
return getField().getMaximumValue(getMillis());
}
/**
* Gets the maximum text length for the field.
*
* @param locale optional locale to use for selecting a text symbol
* @return the maximum length
* @see DateTimeField#getMaximumTextLength
*/
public int getMaximumTextLength(Locale locale) {
return getField().getMaximumTextLength(locale);
}
/**
* Gets the maximum short text length for the field.
*
* @param locale optional locale to use for selecting a text symbol
* @return the maximum length
* @see DateTimeField#getMaximumShortTextLength
*/
public int getMaximumShortTextLength(Locale locale) {
return getField().getMaximumShortTextLength(locale);
}
/**
* Returns the fractional duration milliseconds of this field.
*
* @see DateTimeField#remainder
* @return remainder duration, in milliseconds
*/
public long remainder() {
return getField().remainder(getMillis());
}
/**
* Returns the interval that represents the range of the minimum
* and maximum values of this field.
*
* For example, datetime.monthOfYear().toInterval()
* will return an interval over the whole month.
*
* @return the interval of this field
* @since 1.2
*/
public Interval toInterval() {
DateTimeField field = getField();
long start = field.roundFloor(getMillis());
long end = field.add(start, 1);
Interval interval = new Interval(start, end);
return interval;
}
//-----------------------------------------------------------------------
/**
* Compare this field to the same field on another instant.
*
* The comparison is based on the value of the same field type, irrespective * of any difference in chronology. Thus, if this property represents the * hourOfDay field, then the hourOfDay field of the other instant will be queried * whether in the same chronology or not. * * @param instant the instant to compare to * @return negative value if this is less, 0 if equal, or positive value if greater * @throws IllegalArgumentException if the instant is null */ public int compareTo(ReadableInstant instant) { if (instant == null) { throw new IllegalArgumentException("The instant must not be null"); } int thisValue = get(); int otherValue = instant.get(getFieldType()); if (thisValue < otherValue) { return -1; } else if (thisValue > otherValue) { return 1; } else { return 0; } } //----------------------------------------------------------------------- /** * Compare this field to the same field on another partial instant. *
* The comparison is based on the value of the same field type, irrespective * of any difference in chronology. Thus, if this property represents the * hourOfDay field, then the hourOfDay field of the other partial will be queried * whether in the same chronology or not. * * @param partial the partial to compare to * @return negative value if this is less, 0 if equal, or positive value if greater * @throws IllegalArgumentException if the partial is null * @throws IllegalArgumentException if the partial doesn't support this field */ public int compareTo(ReadablePartial partial) { if (partial == null) { throw new IllegalArgumentException("The partial must not be null"); } int thisValue = get(); int otherValue = partial.get(getFieldType()); if (thisValue < otherValue) { return -1; } else if (thisValue > otherValue) { return 1; } else { return 0; } } //----------------------------------------------------------------------- /** * Compares this property to another. * * @param object the object to compare to * @return true if equal */ public boolean equals(Object object) { if (this == object) { return true; } if (object instanceof AbstractReadableInstantFieldProperty == false) { return false; } AbstractReadableInstantFieldProperty other = (AbstractReadableInstantFieldProperty) object; return get() == other.get() && getFieldType().equals(other.getFieldType()) && FieldUtils.equals(getChronology(), other.getChronology()); } /** * Returns a hashcode compatible with the equals method. * * @return the hashcode */ public int hashCode() { return get() * 17 + getFieldType().hashCode() + getChronology().hashCode(); } //----------------------------------------------------------------------- /** * Output a debugging string. * * @return debugging string */ public String toString() { return "Property[" + getName() + "]"; } }