1 package org.djunits.quantity;
2
3 import org.djunits.quantity.def.Quantity;
4 import org.djunits.unit.AbstractUnit;
5 import org.djunits.unit.UnitRuntimeException;
6 import org.djunits.unit.Unitless;
7 import org.djunits.unit.scale.LinearScale;
8 import org.djunits.unit.scale.Scale;
9 import org.djunits.unit.si.SIUnit;
10 import org.djunits.unit.system.UnitSystem;
11
12 /**
13 * Area is a measure of a two-dimensional surface, expressed in square meters (m2).
14 * <p>
15 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See
16 * for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
17 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
18 * @author Alexander Verbraeck
19 */
20 public class Area extends Quantity<Area>
21 {
22 /** Constant with value zero. */
23 public static final Area ZERO = ofSi(0.0);
24
25 /** Constant with value one. */
26 public static final Area ONE = ofSi(1.0);
27
28 /** Constant with value NaN. */
29 @SuppressWarnings("checkstyle:constantname")
30 public static final Area NaN = ofSi(Double.NaN);
31
32 /** Constant with value POSITIVE_INFINITY. */
33 public static final Area POSITIVE_INFINITY = ofSi(Double.POSITIVE_INFINITY);
34
35 /** Constant with value NEGATIVE_INFINITY. */
36 public static final Area NEGATIVE_INFINITY = ofSi(Double.NEGATIVE_INFINITY);
37
38 /** Constant with value MAX_VALUE. */
39 public static final Area POS_MAXVALUE = ofSi(Double.MAX_VALUE);
40
41 /** Constant with value -MAX_VALUE. */
42 public static final Area NEG_MAXVALUE = ofSi(-Double.MAX_VALUE);
43
44 /** */
45 private static final long serialVersionUID = 600L;
46
47 /**
48 * Instantiate a Area quantity with a unit.
49 * @param valueInUnit the value, expressed in the unit
50 * @param unit the unit in which the value is expressed
51 */
52 public Area(final double valueInUnit, final Area.Unit unit)
53 {
54 super(valueInUnit, unit);
55 }
56
57 /**
58 * Return a Area instance based on an SI value.
59 * @param si the si value
60 * @return the Area instance based on an SI value
61 */
62 public static Area ofSi(final double si)
63 {
64 return new Area(si, Area.Unit.SI);
65 }
66
67 @Override
68 public Area instantiateSi(final double si)
69 {
70 return ofSi(si);
71 }
72
73 @Override
74 public SIUnit siUnit()
75 {
76 return Area.Unit.SI_UNIT;
77 }
78
79 /**
80 * Returns a Area representation of a textual representation of a value with a unit. The String representation that can be
81 * parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces are allowed,
82 * but not required, between the value and the unit.
83 * @param text the textual representation to parse into a Area
84 * @return the Scalar representation of the value in its unit
85 * @throws IllegalArgumentException when the text cannot be parsed
86 * @throws NullPointerException when the text argument is null
87 */
88 public static Area valueOf(final String text)
89 {
90 return Quantity.valueOf(text, ZERO);
91 }
92
93 /**
94 * Returns a Area based on a value and the textual representation of the unit, which can be localized.
95 * @param valueInUnit the value, expressed in the unit as given by unitString
96 * @param unitString the textual representation of the unit
97 * @return the Scalar representation of the value in its unit
98 * @throws IllegalArgumentException when the unit cannot be parsed or is incorrect
99 * @throws NullPointerException when the unitString argument is null
100 */
101 public static Area of(final double valueInUnit, final String unitString)
102 {
103 return Quantity.of(valueInUnit, unitString, ZERO);
104 }
105
106 @Override
107 public Area.Unit getDisplayUnit()
108 {
109 return (Area.Unit) super.getDisplayUnit();
110 }
111
112 /**
113 * Calculate the division of Area and Area, which results in a Dimensionless scalar.
114 * @param v scalar
115 * @return scalar as a division of Area and Area
116 */
117 public final Dimensionless divide(final Area v)
118 {
119 return new Dimensionless(this.si() / v.si(), Unitless.BASE);
120 }
121
122 /**
123 * Calculate the multiplication of Area and ArealObjectDensity, which results in a Dimensionless scalar.
124 * @param v scalar
125 * @return scalar as a multiplication of Area and ArealObjectDensity
126 */
127 public final Dimensionless multiply(final ArealObjectDensity v)
128 {
129 return new Dimensionless(this.si() * v.si(), Unitless.BASE);
130 }
131
132 /**
133 * Calculate the multiplication of Area and Length, which results in a Volume scalar.
134 * @param v scalar
135 * @return scalar as a multiplication of Area and Length
136 */
137 public final Volume multiply(final Length v)
138 {
139 return new Volume(this.si() * v.si(), Volume.Unit.SI);
140 }
141
142 /**
143 * Calculate the division of Area and LinearObjectDensity, which results in a Volume scalar.
144 * @param v scalar
145 * @return scalar as a division of Area and LinearObjectDensity
146 */
147 public final Volume divide(final LinearObjectDensity v)
148 {
149 return new Volume(this.si() / v.si(), Volume.Unit.SI);
150 }
151
152 /**
153 * Calculate the division of Area and Volume, which results in a LinearObjectDensity scalar.
154 * @param v scalar
155 * @return scalar as a division of Area and Volume
156 */
157 public final LinearObjectDensity divide(final Volume v)
158 {
159 return new LinearObjectDensity(this.si() / v.si(), LinearObjectDensity.Unit.SI);
160 }
161
162 /**
163 * Calculate the division of Area and Length, which results in a Length scalar.
164 * @param v scalar
165 * @return scalar as a division of Area and Length
166 */
167 public final Length divide(final Length v)
168 {
169 return new Length(this.si() / v.si(), Length.Unit.SI);
170 }
171
172 /**
173 * Calculate the multiplication of Area and LinearObjectDensity, which results in a Length scalar.
174 * @param v scalar
175 * @return scalar as a multiplication of Area and LinearObjectDensity
176 */
177 public final Length multiply(final LinearObjectDensity v)
178 {
179 return new Length(this.si() * v.si(), Length.Unit.SI);
180 }
181
182 /**
183 * Calculate the multiplication of Area and Speed, which results in a FlowVolume scalar.
184 * @param v scalar
185 * @return scalar as a multiplication of Area and Speed
186 */
187 public final FlowVolume multiply(final Speed v)
188 {
189 return new FlowVolume(this.si() * v.si(), FlowVolume.Unit.SI);
190 }
191
192 /**
193 * Calculate the multiplication of Area and Pressure, which results in a Force scalar.
194 * @param v scalar
195 * @return scalar as a multiplication of Area and Pressure
196 */
197 public final Force multiply(final Pressure v)
198 {
199 return new Force(this.si() * v.si(), Force.Unit.SI);
200 }
201
202 /**
203 * Calculate the multiplication of Area and Illuminance, which results in a LuminousFlux scalar.
204 * @param v scalar
205 * @return scalar as a multiplication of Area and Illuminance
206 */
207 public final LuminousFlux multiply(final Illuminance v)
208 {
209 return new LuminousFlux(this.si() * v.si(), LuminousFlux.Unit.SI);
210 }
211
212 @Override
213 public ArealObjectDensity reciprocal()
214 {
215 return ArealObjectDensity.ofSi(1.0 / this.si());
216 }
217
218 /******************************************************************************************************/
219 /********************************************** UNIT CLASS ********************************************/
220 /******************************************************************************************************/
221
222 /**
223 * Area.Unit encodes the area unit (length x length).
224 * <p>
225 * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
226 * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
227 * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
228 * @author Alexander Verbraeck
229 */
230 @SuppressWarnings("checkstyle:constantname")
231 public static class Unit extends AbstractUnit<Area.Unit, Area>
232 {
233 /** The dimensions of Area: m2. */
234 public static final SIUnit SI_UNIT = SIUnit.of("m2");
235
236 /** Square meter. */
237 public static final Area.Unit m2 = new Area.Unit("m2", "square meter", 1.0, UnitSystem.SI_BASE);
238
239 /** The SI or BASE unit. */
240 public static final Area.Unit SI = m2;
241
242 /** Square kilometer. */
243 public static final Area.Unit km2 = m2.deriveUnit("km2", "square kilometer", 1.0E6, UnitSystem.SI_BASE);
244
245 /** Square hectometer. */
246 public static final Area.Unit hm2 = m2.deriveUnit("hm2", "square hectometer", 1.0E4, UnitSystem.SI_BASE);
247
248 /** Square decameter. */
249 public static final Area.Unit dam2 = m2.deriveUnit("dam2", "square decameter", 1.0E2, UnitSystem.SI_BASE);
250
251 /** Square decimeter. */
252 public static final Area.Unit dm2 = m2.deriveUnit("dm2", "square decimeter", 1.0E-2, UnitSystem.SI_BASE);
253
254 /** Square centimeter. */
255 public static final Area.Unit cm2 = m2.deriveUnit("cm2", "square centimeter", 1.0E-4, UnitSystem.SI_BASE);
256
257 /** Square millimeter. */
258 public static final Area.Unit mm2 = m2.deriveUnit("mm2", "square millimeter", 1.0E-6, UnitSystem.SI_BASE);
259
260 /** Square micrometer. */
261 public static final Area.Unit mum2 =
262 m2.deriveUnit("mum2", "\u03BCm2", "square micrometer", 1.0E-12, UnitSystem.SI_BASE);
263
264 /** Square nanometer. */
265 public static final Area.Unit nm2 = m2.deriveUnit("nm2", "square nanometer", 1.0E-18, UnitSystem.SI_BASE);
266
267 /** Square picometer. */
268 public static final Area.Unit pm2 = m2.deriveUnit("pm2", "square picometer", 1.0E-24, UnitSystem.SI_BASE);
269
270 /** Square femtometer. */
271 public static final Area.Unit fm2 = m2.deriveUnit("fm2", "square femtometer", 1.0E-30, UnitSystem.SI_BASE);
272
273 /** Square attometer. */
274 public static final Area.Unit am2 = m2.deriveUnit("am2", "square attometer", 1.0E-36, UnitSystem.SI_BASE);
275
276 /** centiare. */
277 public static final Area.Unit ca = new Area.Unit("ca", "centiare", 1.0, UnitSystem.OTHER);
278
279 /** are. */
280 public static final Area.Unit a = new Area.Unit("a", "are", 100.0, UnitSystem.OTHER);
281
282 /** hectare. */
283 public static final Area.Unit ha = new Area.Unit("ha", "hectare", 100.0 * 100.0, UnitSystem.OTHER);
284
285 /** mile2. */
286 public static final Area.Unit mi2 =
287 new Area.Unit("mi2", "square mile", Length.Unit.CONST_MI * Length.Unit.CONST_MI, UnitSystem.IMPERIAL);
288
289 /** Nautical mile2. */
290 public static final Area.Unit NM2 =
291 new Area.Unit("NM2", "square nautical mile", Length.Unit.CONST_NM * Length.Unit.CONST_NM, UnitSystem.OTHER);
292
293 /** ft2. */
294 public static final Area.Unit ft2 =
295 new Area.Unit("ft2", "square foot", Length.Unit.CONST_FT * Length.Unit.CONST_FT, UnitSystem.IMPERIAL);
296
297 /** in2. */
298 public static final Area.Unit in2 =
299 new Area.Unit("in2", "square inch", Length.Unit.CONST_IN * Length.Unit.CONST_IN, UnitSystem.IMPERIAL);
300
301 /** yd2. */
302 public static final Area.Unit yd2 =
303 new Area.Unit("yd2", "square yard", Length.Unit.CONST_YD * Length.Unit.CONST_YD, UnitSystem.IMPERIAL);
304
305 /** acre (international) defined as 1/640 square mile or 4840 square yards. */
306 public static final Area.Unit ac =
307 new Area.Unit("ac", "acre", Length.Unit.CONST_MI * Length.Unit.CONST_MI / 640.0, UnitSystem.IMPERIAL);
308
309 /**
310 * Create a new Area unit.
311 * @param id the id or main abbreviation of the unit
312 * @param name the full name of the unit
313 * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
314 * @param unitSystem the unit system such as SI or IMPERIAL
315 */
316 public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
317 {
318 super(id, name, new LinearScale(scaleFactorToBaseUnit), unitSystem);
319 }
320
321 /**
322 * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
323 * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
324 * @param displayAbbreviation the display abbreviation of the unit
325 * @param name the full name of the unit
326 * @param scale the scale to use to convert between this unit and the standard (e.g., SI, BASE) unit
327 * @param unitSystem unit system, e.g. SI or Imperial
328 */
329 public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
330 final UnitSystem unitSystem)
331 {
332 super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem);
333 }
334
335 @Override
336 public SIUnit siUnit()
337 {
338 return SI_UNIT;
339 }
340
341 @Override
342 public Unit getBaseUnit()
343 {
344 return SI;
345 }
346
347 @Override
348 public Area ofSi(final double si)
349 {
350 return Area.ofSi(si);
351 }
352
353 @Override
354 public Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation, final String name,
355 final double scaleFactor, final UnitSystem unitSystem)
356 {
357 if (getScale() instanceof LinearScale ls)
358 {
359 return new Area.Unit(textualAbbreviation, displayAbbreviation, name,
360 new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem);
361 }
362 throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
363 }
364
365 }
366 }