alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (PreciseDurationDateTimeField.java)

This example Java source code file (PreciseDurationDateTimeField.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

basedatetimefield, durationfield, illegalargumentexception, precisedurationdatetimefield, suppresswarnings, the, unit

The PreciseDurationDateTimeField.java Java example source code

/*
 *  Copyright 2001-2013 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.DateTimeFieldType;
import org.joda.time.DurationField;

/**
 * Precise datetime field, which has a precise unit duration field.
 * <p>
 * PreciseDurationDateTimeField is thread-safe and immutable, and its
 * subclasses must be as well.
 *
 * @author Brian S O'Neill
 * @since 1.0
 */
public abstract class PreciseDurationDateTimeField extends BaseDateTimeField {

    @SuppressWarnings("unused")
    private static final long serialVersionUID = 5004523158306266035L;

    /** The fractional unit in millis */
    final long iUnitMillis;

    private final DurationField iUnitField;

    /**
     * Constructor.
     * 
     * @param type  the field type
     * @param unit  precise unit duration, like "days()".
     * @throws IllegalArgumentException if duration field is imprecise
     * @throws IllegalArgumentException if unit milliseconds is less than one
     */
    public PreciseDurationDateTimeField(DateTimeFieldType type, DurationField unit) {
        super(type);

        if (!unit.isPrecise()) {
            throw new IllegalArgumentException("Unit duration field must be precise");
        }

        iUnitMillis = unit.getUnitMillis();
        if (iUnitMillis < 1) {
            throw new IllegalArgumentException("The unit milliseconds must be at least 1");
        }

        iUnitField = unit;
    }

    /**
     * Returns false by default.
     */
    public boolean isLenient() {
        return false;
    }

    /**
     * Set the specified amount of units to the specified time instant.
     * 
     * @param instant  the milliseconds from 1970-01-01T00:00:00Z to set in
     * @param value  value of units to set.
     * @return the updated time instant.
     * @throws IllegalArgumentException if value is too large or too small.
     */
    public long set(long instant, int value) {
        FieldUtils.verifyValueBounds(this, value, getMinimumValue(),
                                     getMaximumValueForSet(instant, value));
        return instant + (value - get(instant)) * iUnitMillis;
    }

    /**
     * This method assumes that this field is properly rounded on
     * 1970-01-01T00:00:00. If the rounding alignment differs, override this
     * method as follows:
     * <pre>
     * return super.roundFloor(instant + ALIGNMENT_MILLIS) - ALIGNMENT_MILLIS;
     * </pre>
     */
    public long roundFloor(long instant) {
        if (instant >= 0) {
            return instant - instant % iUnitMillis;
        } else {
            instant += 1;
            return instant - instant % iUnitMillis - iUnitMillis;
        }
    }

    /**
     * This method assumes that this field is properly rounded on
     * 1970-01-01T00:00:00. If the rounding alignment differs, override this
     * method as follows:
     * <pre>
     * return super.roundCeiling(instant + ALIGNMENT_MILLIS) - ALIGNMENT_MILLIS;
     * </pre>
     */
    public long roundCeiling(long instant) {
        if (instant > 0) {
            instant -= 1;
            return instant - instant % iUnitMillis + iUnitMillis;
        } else {
            return instant - instant % iUnitMillis;
        }
    }

    /**
     * This method assumes that this field is properly rounded on
     * 1970-01-01T00:00:00. If the rounding alignment differs, override this
     * method as follows:
     * <pre>
     * return super.remainder(instant + ALIGNMENT_MILLIS);
     * </pre>
     */
    public long remainder(long instant) {
        if (instant >= 0) {
            return instant % iUnitMillis;
        } else {
            return (instant + 1) % iUnitMillis + iUnitMillis - 1;
        }
    }

    /**
     * Returns the duration per unit value of this field. For example, if this
     * field represents "minute of hour", then the duration field is minutes.
     *
     * @return the duration of this field, or UnsupportedDurationField if field
     * has no duration
     */
    public DurationField getDurationField() {
        return iUnitField;
    }

    /**
     * Get the minimum value for the field.
     * 
     * @return the minimum value
     */
    public int getMinimumValue() {
        return 0;
    }

    public final long getUnitMillis() {
        return iUnitMillis;
    }

    /**
     * Called by the set method to get the maximum allowed value. By default,
     * returns getMaximumValue(instant). Override to provide a faster
     * implementation.
     */
    protected int getMaximumValueForSet(long instant, int value) {
        return getMaximumValue(instant);
    }

}

Other Java examples (source code examples)

Here is a short list of links related to this Java PreciseDurationDateTimeField.java source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.