timeattribute.java

sunxacml源码

/*
 * @(#)TimeAttribute.java
 *
 * Copyright 2003-2006 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistribution of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 * 
 *   2. Redistribution in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 * 
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *
 * You acknowledge that this software is not designed or intended for use in
 * the design, construction, operation or maintenance of any nuclear facility.
 */

package com.sun.xacml.attr;

import com.sun.xacml.ParsingException;
import com.sun.xacml.ProcessingException;

import java.net.URI;

import java.text.ParseException;

import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.TimeZone;

import org.w3c.dom.Node;


/**
 * Representation of an xs:time value. This class supports parsing
 * xs:time values. All objects of this class are immutable and
 * thread-safe. The <code>Date</code> objects returned are not, but
 * these objects are cloned before being returned.
 *
 * @since 1.0
 * @author Steve Hanna
 * @author Seth Proctor
 */
public class TimeAttribute extends AttributeValue
{
    /**
     * Official name of this type
     */
    public static final String identifier =
        "http://www.w3.org/2001/XMLSchema#time";
 
    /**
     * URI version of name for this type
     * <p>
     * This field is initialized by a static initializer so that
     * we can catch any exceptions thrown by URI(String) and
     * transform them into a RuntimeException, since this should
     * never happen but should be reported properly if it ever does.
     * <p>
     * This object is used for synchronization whenever we need
     * protection across this whole class.
     */
    private static URI identifierURI;

    /**
     * RuntimeException that wraps an Exception thrown during the
     * creation of identifierURI, null if none.
     */
    private static RuntimeException earlyException;

    /**
     * Static initializer that initializes the identifierURI
     * class field so that we can catch any exceptions thrown
     * by URI(String) and transform them into a RuntimeException.
     * Such exceptions should never happen but should be reported
     * properly if they ever do.
     */
    static {
        try {
            identifierURI = new URI(identifier);
        } catch (Exception e) {
            earlyException = new IllegalArgumentException();
            earlyException.initCause(e);
        }
    };

    /**
     * Time zone value that indicates that the time zone was not
     * specified.
     */
    public static final int TZ_UNSPECIFIED = -1000000;

    /**
     * The time that this object represents in second resolution, in
     * milliseconds GMT, with zero being midnight. If no time zone was
     * specified, the local time zone is used to convert to milliseconds
     * relative to GMT.
     */
    private long timeGMT;

    /**
     * The number of nanoseconds beyond the time given by the timeGMT
     * field. The XML Query document says that fractional seconds
     * must be supported down to at least 100 nanosecond resolution.
     * The Date class only supports milliseconds, so we include here
     * support for nanosecond resolution.
     */
    private int nanoseconds;

    // NOTE: now that we're not using a Date object, the above two variables
    // could be condensed, and the interface could be changed so we don't
    // need to worry about tracking the time values separately

    /**
     * The time zone specified for this object (or TZ_UNSPECIFIED if
     * unspecified). The offset to GMT, in minutes.
     */
    private int timeZone;

    /**
     * The time zone actually used for this object (if it was
     * originally unspecified, the default time zone used).
     * The offset to GMT, in minutes.
     */
    private int defaultedTimeZone;

    /**
     * Cached encoded value (null if not cached yet).
     */
    private String encodedValue = null;

    /**
     * Creates a new <code>TimeAttribute</code> that represents
     * the current time in the current time zone.
     */
    public TimeAttribute() {
        this(new Date());
    }

    /**
     * Creates a new <code>TimeAttribute</code> that represents
     * the given time but uses the default timezone and offset values.
     *
     * @param time a <code>Date</code> object representing the
     *             specified time down to second resolution. This
     *             date should have a date of 01/01/1970. If it does
     *             not, such a date will be forced. If this object
     *             has non-zero milliseconds, they are combined
     *             with the nanoseconds parameter.
     */
    public TimeAttribute(Date time) {
        super(identifierURI);

        int currOffset = DateTimeAttribute.getDefaultTZOffset(time);
        init(time, 0, currOffset, currOffset);
    }

    /**
     * Creates a new <code>TimeAttribute</code> that represents
     * the time supplied.
     *
     * @param time a <code>Date</code> object representing the
     *             specified time down to second resolution. This
     *             date should have a date of 01/01/1970. If it does
     *             not, such a date will be forced. If this object
     *             has non-zero milliseconds, they are combined
     *             with the nanoseconds parameter.
     * @param nanoseconds the number of nanoseconds beyond the
     *                    Date specified in the date parameter
     * @param timeZone the time zone specified for this object
     *                 (or TZ_UNSPECIFIED if unspecified). The
     *                 offset to GMT, in minutes.
     * @param defaultedTimeZone the time zone actually used for this
     *                          object, which must be specified.
     *                          The offset to GMT, in minutes.
     */
    public TimeAttribute(Date time, int nanoseconds, int timeZone,
                         int defaultedTimeZone) {
        super(identifierURI);

        // if the timezone is unspecified, it's illegal for the defaulted
        // timezone to also be unspecified
        if ((timeZone == TZ_UNSPECIFIED) &&
            (defaultedTimeZone == TZ_UNSPECIFIED))
            throw new ProcessingException("default timezone must be specified"
                                          + "when a timezone is provided");

        init(time, nanoseconds, timeZone, defaultedTimeZone);
    }

    /**
     * Initialization code shared by constructors.
     *
     * @param date a <code>Date</code> object representing the
     *             specified time down to second resolution. This
     *             date should have a date of 01/01/1970. If it does
     *             not, such a date will be forced. If this object
     *             has non-zero milliseconds, they are combined
     *             with the nanoseconds parameter.
     * @param nanoseconds the number of nanoseconds beyond the
     *                    Date specified in the date parameter
     * @param timeZone the time zone specified for this object
     *                 (or TZ_UNSPECIFIED if unspecified). The
     *                 offset to GMT, in minutes.
     * @param defaultedTimeZone the time zone actually used for this
     *                          object (if it was originally unspecified,
     *                          the default time zone used).
     *                          The offset to GMT, in minutes.
     */
    private void init(Date date, int nanoseconds, int timeZone,
                      int defaultedTimeZone) {

        // Shouldn't happen, but just in case...
        if (earlyException != null)
            throw earlyException;

        // get a temporary copy of the date
        Date tmpDate = (Date)(date.clone());

        // Combine the nanoseconds so they are between 0 and 999,999,999
        this.nanoseconds =
            DateTimeAttribute.combineNanos(tmpDate, nanoseconds);

        // now that the date has been (potentially) updated, store the time
        this.timeGMT = tmpDate.getTime();

        // keep track of the timezone values
        this.timeZone = timeZone;
        this.defaultedTimeZone = defaultedTimeZone;

        // Check that the date is normalized to 1/1/70
        if ((timeGMT >= DateAttribute.MILLIS_PER_DAY) || (timeGMT < 0)) {
            timeGMT = timeGMT % DateAttribute.MILLIS_PER_DAY;