001 //$HeadURL: https://svn.wald.intevation.org/svn/deegree/base/branches/2.3_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 >>>32))</li>
227 * <li>float -- code = Float.floatToIntBits(f);</li>
228 * <li>double -- long l = Double.doubleToLongBits(f); code = (int)(l ^ (l >>> 32))</li>
229 * <li>all Objects, (where equals( ) calls equals( ) for this field) -- code = f.hashCode( )</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 }