http://www.joda.org/joda-time/: Date and time library to replace JDK date handling (Joda.org) 
/*
 *  Copyright 2001-2006 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.util.Locale;

import org.joda.time.DateTimeField;
import org.joda.time.DateTimeFieldType;
import org.joda.time.DurationField;
import org.joda.time.ReadableInstant;
import org.joda.time.ReadablePartial;


AbstractPartialFieldProperty is a base class for binding a
ReadablePartial to a DateTimeField.


It allows the date and time manipulation code to be field based yet
still easy to use.

Author:Stephen Colebourne, Brian S O'Neill
Since:1.0
/**
 * AbstractPartialFieldProperty is a base class for binding a
 * ReadablePartial to a DateTimeField.
 * <p>
 * It allows the date and time manipulation code to be field based yet
 * still easy to use.
 *
 * @author Stephen Colebourne
 * @author Brian S O'Neill
 * @since 1.0
 */
public abstract class AbstractPartialFieldProperty {

    
Constructor.

/**
     * Constructor.
     */
    protected AbstractPartialFieldProperty() {
        super();
    }

    //-----------------------------------------------------------------------
    
Gets the field being used.

Returns:the field
/**
     * Gets the field being used.
     * 
     * @return the field
     */
    public abstract DateTimeField getField();

    
Gets the field type being used.

Returns:the field type
/**
     * Gets the field type being used.
     * 
     * @return the field type
     */
    public DateTimeFieldType getFieldType() {
        return getField().getType();
    }

    
Gets the name of the field.

Returns:the field name
/**
     * Gets the name of the field.
     * 
     * @return the field name
     */
    public String getName() {
        return getField().getName();
    }

    
Gets the partial instant being used.

Returns:the partial instant
/**
     * Gets the partial instant being used.
     * 
     * @return the partial instant
     */
    protected abstract ReadablePartial getReadablePartial();

    //-----------------------------------------------------------------------
    
Gets the value of this property from the instant.


For example, the following two lines of code are equivalent:

partial.getDayOfMonth();
partial.dayOfMonth().get();



Returns:the current value
/**
     * Gets the value of this property from the instant.
     * <p>
     * For example, the following two lines of code are equivalent:
     * <pre>
     * partial.getDayOfMonth();
     * partial.dayOfMonth().get();
     * </pre>
     * 
     * @return the current value
     */
    public abstract int get();

    
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 getAsText() and getAsShortText() for those. 
See Also:
Returns:the current value
Since:1.1
/**
     * 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.


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.

See Also:
Returns:the current text value
/**
     * 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.


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.

Params:
  • locale –  locale to use for selecting a text symbol, null means default
See Also:
Returns:the current text value
/**
     * 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(getReadablePartial(), get(), 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.

See Also:
Returns:the current text value
/**
     * 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.


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.

Params:
  • locale –  locale to use for selecting a text symbol, null means default
See Also:
Returns:the current text value
/**
     * 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(getReadablePartial(), get(), locale);
    }

    //-----------------------------------------------------------------------
    
Returns the duration per unit value of this field. For example, if this
field represents "hour of day", then the duration is an hour.

Returns:the duration of this field, or UnsupportedDurationField
/**
     * 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.

Returns:the range duration of this field, or null if field has no range
/**
     * 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 the minimum value for the field ignoring the current time.

See Also:
Returns:the minimum value
/**
     * 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 this field given the current field values.

See Also:
Returns:the minimum value
/**
     * Gets the minimum value for this field given the current field values.
     * 
     * @return the minimum value
     * @see DateTimeField#getMinimumValue
     */
    public int getMinimumValue() {
        return getField().getMinimumValue(getReadablePartial());
    }

    
Gets the maximum value for the field ignoring the current time.

See Also:
Returns:the maximum value
/**
     * 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 this field given the current field values.

See Also:
Returns:the maximum value
/**
     * Gets the maximum value for this field given the current field values.
     * 
     * @return the maximum value
     * @see DateTimeField#getMaximumValue
     */
    public int getMaximumValue() {
        return getField().getMaximumValue(getReadablePartial());
    }

    //-----------------------------------------------------------------------
    
Gets the maximum text length for the field.

Params:
  • locale –  optional locale to use for selecting a text symbol
See Also:
Returns:the maximum length
/**
     * 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.

Params:
  • locale –  optional locale to use for selecting a text symbol
See Also:
Returns:the maximum length
/**
     * 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);
    }

    //-----------------------------------------------------------------------
    
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.

Params:
  • instant –  the instant to compare to
Throws:
Returns:negative value if this is less, 0 if equal, or positive value if greater
/**
     * 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 or the instant
     *  doesn't support the field of this property
     */
    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.

Params:
  • partial –  the partial to compare to
Throws:
Returns:negative value if this is less, 0 if equal, or positive value if greater
/**
     * 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 instant is null
     * @throws IllegalArgumentException if the field of this property cannot be queried
     *  on the specified instant
     */
    public int compareTo(ReadablePartial partial) {
        if (partial == null) {
            throw new IllegalArgumentException("The instant 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.

Params:
  • object –  the object to compare to
Returns:true if equal
/**
     * 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 AbstractPartialFieldProperty == false) {
            return false;
        }
        AbstractPartialFieldProperty other = (AbstractPartialFieldProperty) object;
        return
            get() == other.get() &&
            getFieldType() == other.getFieldType() &&
            FieldUtils.equals(getReadablePartial().getChronology(), other.getReadablePartial().getChronology());
    }

    //-----------------------------------------------------------------------
    
Gets a suitable hashcode for the object.

Returns:the hashcode
Since:1.3
/**
     * Gets a suitable hashcode for the object.
     * 
     * @return the hashcode
     * @since 1.3
     */
    public int hashCode() {
        int hash = 19;
        hash = 13 * hash + get();
        hash = 13 * hash + getFieldType().hashCode();
        hash = 13 * hash + getReadablePartial().getChronology().hashCode();
        return hash;
    }

    //-----------------------------------------------------------------------
    
Output a debugging string.

Returns:debugging string
/**
     * Output a debugging string.
     * 
     * @return debugging string
     */
    public String toString() {
        return "Property[" + getName() + "]";
    }

}