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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.Units;
8   import org.djunits.unit.scale.LinearScale;
9   import org.djunits.unit.scale.Scale;
10  import org.djunits.unit.si.SIUnit;
11  import org.djunits.unit.system.UnitSystem;
12  
13  /**
14   * Mass is the amount of matter in an object, measured in kilograms (kg).
15   * <p>
16   * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See
17   * for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
18   * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
19   * @author Alexander Verbraeck
20   */
21  public class Mass extends Quantity<Mass, Mass.Unit>
22  {
23      /** Constant with value zero. */
24      public static final Mass ZERO = Mass.ofSi(0.0);
25  
26      /** Constant with value one. */
27      public static final Mass ONE = Mass.ofSi(1.0);
28  
29      /** Constant with value NaN. */
30      @SuppressWarnings("checkstyle:constantname")
31      public static final Mass NaN = Mass.ofSi(Double.NaN);
32  
33      /** Constant with value POSITIVE_INFINITY. */
34      public static final Mass POSITIVE_INFINITY = Mass.ofSi(Double.POSITIVE_INFINITY);
35  
36      /** Constant with value NEGATIVE_INFINITY. */
37      public static final Mass NEGATIVE_INFINITY = Mass.ofSi(Double.NEGATIVE_INFINITY);
38  
39      /** Constant with value MAX_VALUE. */
40      public static final Mass POS_MAXVALUE = Mass.ofSi(Double.MAX_VALUE);
41  
42      /** Constant with value -MAX_VALUE. */
43      public static final Mass NEG_MAXVALUE = Mass.ofSi(-Double.MAX_VALUE);
44  
45      /** */
46      private static final long serialVersionUID = 600L;
47  
48      /**
49       * Instantiate a Mass quantity with a unit.
50       * @param value the value, expressed in the unit
51       * @param unit the unit in which the value is expressed
52       */
53      public Mass(final double value, final Mass.Unit unit)
54      {
55          super(value, unit);
56      }
57  
58      /**
59       * Instantiate a Mass quantity with a unit, expressed as a String.
60       * @param value the value, expressed in the unit
61       * @param abbreviation the String abbreviation of the unit in which the value is expressed
62       */
63      public Mass(final double value, final String abbreviation)
64      {
65          this(value, Units.resolve(Mass.Unit.class, abbreviation));
66      }
67  
68      /**
69       * Construct Mass quantity.
70       * @param value Scalar from which to construct this instance
71       */
72      public Mass(final Mass value)
73      {
74          super(value.si(), Mass.Unit.SI);
75          setDisplayUnit(value.getDisplayUnit());
76      }
77  
78      /**
79       * Return a Mass instance based on an SI value.
80       * @param si the si value
81       * @return the Mass instance based on an SI value
82       */
83      public static Mass ofSi(final double si)
84      {
85          return new Mass(si, Mass.Unit.SI);
86      }
87  
88      @Override
89      public Mass instantiate(final double si)
90      {
91          return ofSi(si);
92      }
93  
94      @Override
95      public SIUnit siUnit()
96      {
97          return Mass.Unit.SI_UNIT;
98      }
99  
100     /**
101      * Returns a Mass representation of a textual representation of a value with a unit. The String representation that can be
102      * parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces are allowed,
103      * but not required, between the value and the unit.
104      * @param text the textual representation to parse into a Mass
105      * @return the Scalar representation of the value in its unit
106      * @throws IllegalArgumentException when the text cannot be parsed
107      * @throws NullPointerException when the text argument is null
108      */
109     public static Mass valueOf(final String text)
110     {
111         return Quantity.valueOf(text, ZERO);
112     }
113 
114     /**
115      * Returns a Mass based on a value and the textual representation of the unit, which can be localized.
116      * @param value the value to use
117      * @param unitString the textual representation of the unit
118      * @return the Scalar representation of the value in its unit
119      * @throws IllegalArgumentException when the unit cannot be parsed or is incorrect
120      * @throws NullPointerException when the unitString argument is null
121      */
122     public static Mass of(final double value, final String unitString)
123     {
124         return Quantity.of(value, unitString, ZERO);
125     }
126 
127     /**
128      * Calculate the division of Mass and Mass, which results in a Dimensionless quantity.
129      * @param v quantity
130      * @return quantity as a division of Mass and Mass
131      */
132     public final Dimensionless divide(final Mass v)
133     {
134         return new Dimensionless(this.si() / v.si(), Unitless.BASE);
135     }
136 
137     /**
138      * Calculate the division of Mass and FlowMass, which results in a Duration scalar.
139      * @param v scalar
140      * @return scalar as a division of Mass and FlowMass
141      */
142     public final Duration divide(final FlowMass v)
143     {
144         return new Duration(this.si() / v.si(), Duration.Unit.SI);
145     }
146 
147     /**
148      * Calculate the division of Mass and Duration, which results in a FlowMass scalar.
149      * @param v scalar
150      * @return scalar as a division of Mass and Duration
151      */
152     public final FlowMass divide(final Duration v)
153     {
154         return new FlowMass(this.si() / v.si(), FlowMass.Unit.SI);
155     }
156 
157     /**
158      * Calculate the multiplication of Mass and Acceleration, which results in a Force scalar.
159      * @param v scalar
160      * @return scalar as a multiplication of Mass and Acceleration
161      */
162     public final Force multiply(final Acceleration v)
163     {
164         return new Force(this.si() * v.si(), Force.Unit.SI);
165     }
166 
167     /**
168      * Calculate the multiplication of Mass and Frequency, which results in a FlowMass scalar.
169      * @param v scalar
170      * @return scalar as a multiplication of Mass and Frequency
171      */
172     public final FlowMass multiply(final Frequency v)
173     {
174         return new FlowMass(this.si() * v.si(), FlowMass.Unit.SI);
175     }
176 
177     /**
178      * Calculate the division of Mass and Density, which results in a Volume scalar.
179      * @param v scalar
180      * @return scalar as a division of Mass and Density
181      */
182     public final Volume divide(final Density v)
183     {
184         return new Volume(this.si() / v.si(), Volume.Unit.SI);
185     }
186 
187     /**
188      * Calculate the division of Mass and Volume, which results in a Density scalar.
189      * @param v scalar
190      * @return scalar as a division of Mass and Volume
191      */
192     public final Density divide(final Volume v)
193     {
194         return new Density(this.si() / v.si(), Density.Unit.SI);
195     }
196 
197     /**
198      * Calculate the multiplication of Mass and Speed, which results in a Momentum scalar.
199      * @param v scalar
200      * @return scalar as a multiplication of Mass and Speed
201      */
202     public final Momentum multiply(final Speed v)
203     {
204         return new Momentum(this.si() * v.si(), Momentum.Unit.SI);
205     }
206 
207     /******************************************************************************************************/
208     /********************************************** UNIT CLASS ********************************************/
209     /******************************************************************************************************/
210 
211     /**
212      * Mass.Unit encodes the unit of the amount of matter in an object.
213      * <p>
214      * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
215      * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
216      * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
217      * @author Alexander Verbraeck
218      */
219     @SuppressWarnings("checkstyle:constantname")
220     public static class Unit extends AbstractUnit<Mass.Unit, Mass>
221     {
222         /** Constant for pound (lb). */
223         public static final double CONST_LB = 0.45359237;
224 
225         /** Constant for ounce. */
226         public static final double CONST_OUNCE = CONST_LB / 16.0;
227 
228         /** Constant for short ton. */
229         public static final double CONST_TON_SHORT = 2000.0 * CONST_LB;
230 
231         /** Constant for long ton. */
232         public static final double CONST_TON_LONG = 2240.0 * CONST_LB;
233 
234         /** The dimensions of mass: kg. */
235         public static final SIUnit SI_UNIT = SIUnit.of("kg");
236 
237         /** kilogram. */
238         public static final Mass.Unit kg = new Mass.Unit("kg", "kilogram", 1.0, UnitSystem.SI_BASE);
239 
240         /** The SI or BASE unit. */
241         public static final Mass.Unit SI = kg.generateSiPrefixes(true, false);
242 
243         /** gram. */
244         public static final Mass.Unit g = Units.resolve(Mass.Unit.class, "g");
245 
246         /** microgram. */
247         public static final Mass.Unit mug = Units.resolve(Mass.Unit.class, "mug");
248 
249         /** milligram. */
250         public static final Mass.Unit mg = Units.resolve(Mass.Unit.class, "mg");
251 
252         /** pound. */
253         public static final Mass.Unit lb = kg.deriveUnit("lb", "pound", CONST_LB, UnitSystem.IMPERIAL);
254 
255         /** ounce. */
256         public static final Mass.Unit oz = kg.deriveUnit("oz", "ounce", CONST_OUNCE, UnitSystem.IMPERIAL);
257 
258         /** long ton = 2240 lb. */
259         public static final Mass.Unit long_tn = kg.deriveUnit("long tn", "long ton", CONST_TON_LONG, UnitSystem.IMPERIAL);
260 
261         /** short ton = 2000 lb. */
262         public static final Mass.Unit sh_tn = kg.deriveUnit("sh tn", "short ton", CONST_TON_SHORT, UnitSystem.US_CUSTOMARY);
263 
264         /** metric ton = 1000 kg. */
265         public static final Mass.Unit t = kg.deriveUnit("t", "metric tonne", 1000.0, UnitSystem.SI_ACCEPTED);
266 
267         /** metric ton = 1000 kg. */
268         public static final Mass.Unit t_mts = kg.deriveUnit("t(mts)", "tonne", 1000.0, UnitSystem.MTS);
269 
270         /** Dalton, according to CODATA 2018. */
271         public static final Mass.Unit Da = kg.deriveUnit("Da", "Dalton", 1.66053906660E-27, UnitSystem.SI_ACCEPTED);
272 
273         /** electronvolt = 1.782661907E-36 kg. See http://physics.nist.gov/cuu/Constants/Table/allascii.txt. */
274         public static final Mass.Unit eV = kg.deriveUnit("eV", "electronvolt", 1.782661907E-36, UnitSystem.OTHER);
275 
276         /** microelectronvolt. */
277         public static final Mass.Unit mueV = eV.deriveUnit("mueV", "\u03BCeV", "microelectronvolt", 1E-6, UnitSystem.OTHER);
278 
279         /** millielectronvolt (note, no dash between milli and electron; the SI style guide forbids spaces or hyphens). */
280         public static final Mass.Unit meV = eV.deriveUnit("meV", "millielectronvolt", 1E-3, UnitSystem.OTHER);
281 
282         /** kiloelectronvolt. */
283         public static final Mass.Unit keV = eV.deriveUnit("keV", "kiloelectronvolt", 1E3, UnitSystem.OTHER);
284 
285         /** megaelectronvolt. */
286         public static final Mass.Unit MeV = eV.deriveUnit("MeV", "megaelectronvolt", 1E6, UnitSystem.OTHER);
287 
288         /** gigaelectronvolt. */
289         public static final Mass.Unit GeV = eV.deriveUnit("GeV", "gigaelectronvolt", 1E9, UnitSystem.OTHER);
290 
291         /**
292          * Create a new Mass unit.
293          * @param id the id or main abbreviation of the unit
294          * @param name the full name of the unit
295          * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
296          * @param unitSystem the unit system such as SI or IMPERIAL
297          */
298         public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
299         {
300             super(id, name, new LinearScale(scaleFactorToBaseUnit), unitSystem);
301         }
302 
303         /**
304          * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
305          * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
306          * @param displayAbbreviation the display abbreviation of the unit
307          * @param name the full name of the unit
308          * @param scale the scale to use to convert between this unit and the standard (e.g., SI, BASE) unit
309          * @param unitSystem unit system, e.g. SI or Imperial
310          */
311         public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
312                 final UnitSystem unitSystem)
313         {
314             super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem);
315         }
316 
317         @Override
318         public SIUnit siUnit()
319         {
320             return SI_UNIT;
321         }
322 
323         @Override
324         public Unit getBaseUnit()
325         {
326             return SI;
327         }
328 
329         @Override
330         public Mass ofSi(final double si)
331         {
332             return Mass.ofSi(si);
333         }
334 
335         @Override
336         public Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation, final String name,
337                 final double scaleFactor, final UnitSystem unitSystem)
338         {
339             if (getScale() instanceof LinearScale ls)
340             {
341                 return new Mass.Unit(textualAbbreviation, displayAbbreviation, name,
342                         new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem);
343             }
344             throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
345         }
346 
347     }
348 }