/*
* 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.
* <p>
* It allows the date and time manipulation code to be field based yet
* still easy to use.
* <p>
* 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.
* <p>
* 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.
* <p>
* For example, the following two lines of code are equivalent:
* <pre>
* datetime.getDayOfMonth();
* datetime.dayOfMonth().get();
* </pre>
*
* @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.
* <p>
* This method returns the value converted to a <code>String</code>
* using <code>Integer.toString</code>. 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.
* <p>
* This method returns the value converted to a <code>String</code>
* 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.
* <p>
* This method returns the value converted to a <code>String</code>
* 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.
* <p>
* This method returns the value converted to a <code>String</code>
* 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.
* <p>
* This method returns the value converted to a <code>String</code>
* 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.
* <p>
* For example, <code>datetime.monthOfYear().toInterval()</code>
* 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.
* <p>
* 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.
* <p>
* 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() + "]";
}
}