    001    //$HeadURL: https://svn.wald.intevation.org/svn/deegree/base/branches/2.4_testing/src/org/deegree/crs/components/PrimeMeridian.java $
    002    /*----------------------------------------------------------------------------
    003     This file is part of deegree, http://deegree.org/
    004     Copyright (C) 2001-2009 by:
    005       Department of Geography, University of Bonn
    006     and
    007       lat/lon GmbH
    008
    009     This library is free software; you can redistribute it and/or modify it under
    010     the terms of the GNU Lesser General Public License as published by the Free
    011     Software Foundation; either version 2.1 of the License, or (at your option)
    012     any later version.
    013     This library is distributed in the hope that it will be useful, but WITHOUT
    014     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
    015     FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
    016     details.
    017     You should have received a copy of the GNU Lesser General Public License
    018     along with this library; if not, write to the Free Software Foundation, Inc.,
    019     59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
    020
    021     Contact information:
    022
    023     lat/lon GmbH
    024     Aennchenstr. 19, 53177 Bonn
    025     Germany
    026     http://lat-lon.de/
    027
    028     Department of Geography, University of Bonn
    029     Prof. Dr. Klaus Greve
    030     Postfach 1147, 53001 Bonn
    031     Germany
    032     http://www.geographie.uni-bonn.de/deegree/
    033
    034     e-mail: info@deegree.org
    035    ----------------------------------------------------------------------------*/
    036
    037    package org.deegree.crs.components;
    038
    039    import static org.deegree.crs.projections.ProjectionUtils.EPS11;
    040
    041    import java.io.Serializable;
    042
    043    import org.deegree.crs.Identifiable;
    044
    045    /**
    046     * The <code>PrimeMeridian</code> class saves the longitude to the greenwich meridian.
    047     *
    048     * @author <a href="mailto:bezema@lat-lon.de">Rutger Bezema</a>
    049     *
    050     * @author last edited by: $Author: mschneider $
    051     *
    052     * @version $Revision: 18195 $, $Date: 2009-06-18 17:55:39 +0200 (Do, 18. Jun 2009) $
    053     *
    054     */
    055
    056    public class PrimeMeridian extends Identifiable implements Serializable {
    057
    058        private static final long serialVersionUID = -3719400673666655763L;
    059
    060        private double longitude;
    061
    062        private Unit units;
    063
    064        /**
    065         * The PrimeMeridian of greenwich with epsg:8901 code and radian units.
    066         */
    067        public static final PrimeMeridian GREENWICH = new PrimeMeridian(
    068                                                                         Unit.DEGREE,
    069                                                                         0,
    070                                                                         new String[] {
    071                                                                                       "EPSG:8901",
    072                                                                                       "HTTP://WWW.OPENGIS.NET/GML/SRS/EPSG.XML#8901",
    073                                                                                       "URN:OPENGIS:DEF:CRS:EPSG::8901",
    074                                                                                       "URN:OGC:DEF:CRS:EPSG::8901" },
    075                                                                         new String[] { "Greenwich" },
    076                                                                         new String[] { "1995-06-02" }, null, null );
    077
    078        /**
    079         * @param units
    080         *            Angular units of longitude, normally radians.
    081         * @param longitude
    082         *            (in given units) normally radians.
    083         * @param id
    084         *            to be cloned
    085         */
    086        public PrimeMeridian( Unit units, double longitude, Identifiable id ) {
    087            super( id );
    088            this.units = units;
    089            this.longitude = longitude;
    090        }
    091
    092        /**
    093         * @param units
    094         *            Angular units of longitude, normally radians.
    095         * @param longitude
    096         *            (in given units) normally radians.
    097         * @param identifiers
    098         * @param names
    099         * @param versions
    100         * @param descriptions
    101         * @param areasOfUse
    102         */
    103        public PrimeMeridian( Unit units, double longitude, String[] identifiers, String[] names, String[] versions,
    104                              String[] descriptions, String[] areasOfUse ) {
    105            this( units, longitude, new Identifiable( identifiers, names, versions, descriptions, areasOfUse ) );
    106        }
    107
    108        /**
    109         * @param units
    110         *            Angular units of longitude.
    111         * @param longitude
    112         * @param identifier
    113         * @param name
    114         * @param version
    115         * @param description
    116         * @param areaOfUse
    117         */
    118        public PrimeMeridian( Unit units, double longitude, String identifier, String name, String version,
    119                              String description, String areaOfUse ) {
    120            this( units, longitude, new String[] { identifier }, new String[] { name }, new String[] { version },
    121                  new String[] { description }, new String[] { areaOfUse } );
    122        }
    123
    124        /**
    125         * @param units
    126         *            Angular units of longitude.
    127         * @param longitude
    128         * @param identifiers
    129         */
    130        public PrimeMeridian( Unit units, double longitude, String[] identifiers ) {
    131            this( units, longitude, identifiers, null, null, null, null );
    132        }
    133
    134        /**
    135         * @param units
    136         *            Angular units of longitude.
    137         * @param longitude
    138         * @param identifier
    139         */
    140        public PrimeMeridian( Unit units, double longitude, String identifier ) {
    141            this( units, longitude, new String[] { identifier } );
    142        }
    143
    144        /**
    145         * A Prime meredian with 0 degrees longitude from the greenwich meridian.
    146         *
    147         * @param units
    148         *            Angular units of longitude.
    149         * @param identifiers
    150         */
    151        public PrimeMeridian( Unit units, String[] identifiers ) {
    152            this( units, 0, identifiers );
    153        }
    154
    155        /**
    156         * A Prime meredian with 0 degrees longitude from the greenwich meridian.
    157         *
    158         * @param units
    159         *            Angular units of longitude.
    160         * @param identifier
    161         * @param name
    162         *            human readable name
    163         */
    164        public PrimeMeridian( Unit units, String identifier, String name ) {
    165            this( units, 0, new String[] { identifier }, new String[] { name }, null, null, null );
    166        }
    167
    168        /**
    169         * @return the longitude value relative to the Greenwich Meridian. The longitude is expressed in this objects
    170         *         angular units.
    171         */
    172        public double getLongitude() {
    173            return longitude;
    174        }
    175
    176        /**
    177         * @param targetUnit
    178         *            The unit in which to express longitude.
    179         * @return the longitude value relative to the Greenwich Meridian, expressed in the specified units. This
    180         *         convenience method make easier to obtains longitude in degrees (<code>getLongitude(Unit.DEGREE)</code>),
    181         *         no matter the underlying angular unit of this prime meridian.
    182         */
    183        public double getLongitude( final Unit targetUnit ) {
    184            return getAngularUnit().convert( getLongitude(), targetUnit );
    185        }
    186
    187        /**
    188         * @return the longitude value relative to the Greenwich Meridian, expressed in the radians.
    189         */
    190        public double getLongitudeAsRadian() {
    191            return getAngularUnit().convert( getLongitude(), Unit.RADIAN );
    192        }
    193
    194        /**
    195         * @return the angular unit.
    196         */
    197        public Unit getAngularUnit() {
    198            return units;
    199        }
    200
    201        @Override
    202        public boolean equals( Object other ) {
    203            if ( other != null && other instanceof PrimeMeridian ) {
    204                PrimeMeridian that = (PrimeMeridian) other;
    205                return ( Math.abs( this.longitude - that.longitude ) < EPS11 )
    206                       && ( ( this.units != null ) ? this.units.equals( that.units ) : ( that.units == null ) )
    207                       && super.equals( that );
    208            }
    209            return false;
    210        }
    211
    212        @Override
    213        public String toString() {
    214            StringBuilder sb = new StringBuilder( super.toString() );
    215            sb.append( ", Units: " ).append( units );
    216            sb.append( ", longitude: " ).append( longitude );
    217            return sb.toString();
    218        }
    219
    220        /**
    221         * Implementation as proposed by Joshua Block in Effective Java (Addison-Wesley 2001), which supplies an even
    222         * distribution and is relatively fast. It is created from field <b>f</b> as follows:
    223         * <ul>
    224         * <li>boolean -- code = (f ? 0 : 1)</li>
    225         * <li>byte, char, short, int -- code = (int)f</li>
    226         * <li>long -- code = (int)(f ^ (f &gt;&gt;&gt;32))</li>
    227         * <li>float -- code = Float.floatToIntBits(f);</li>
    228         * <li>double -- long l = Double.doubleToLongBits(f); code = (int)(l ^ (l &gt;&gt;&gt; 32))</li>
    229         * <li>all Objects, (where equals(&nbsp;) calls equals(&nbsp;) for this field) -- code = f.hashCode(&nbsp;)</li>
    230         * <li>Array -- Apply above rules to each element</li>
    231         * </ul>
    232         * <p>
    233         * Combining the hash code(s) computed above: result = 37 * result + code;
    234         * </p>
    235         *
    236         * @return (int) ( result >>> 32 ) ^ (int) result;
    237         *
    238         * @see java.lang.Object#hashCode()
    239         */
    240        @Override
    241        public int hashCode() {
    242            // the 2.nd million th. prime, :-)
    243            long code = 32452843;
    244            long ll = Double.doubleToLongBits( longitude );
    245            code = code * 37 + (int) ( ll ^ ( ll >>> 32 ) );
    246            if ( units != null ) {
    247                code = code * 37 + units.hashCode();
    248            }
    249            return (int) ( code >>> 32 ) ^ (int) code;
    250        }
    251
    252    }