1 package org.djunits.unit;
2
3 import static org.djunits.unit.unitsystem.UnitSystem.SI_DERIVED;
4
5 import org.djunits.unit.unitsystem.UnitSystem;
6
7 /**
8 * Standard solid angle unit.
9 * <p>
10 * Copyright (c) 2015-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
11 * BSD-style license. See <a href="http://djunits.org/docs/license.html">DJUNITS License</a>.
12 * <p>
13 * $LastChangedDate: 2019-01-18 00:35:01 +0100 (Fri, 18 Jan 2019) $, @version $Revision: 324 $, by $Author: averbraeck $,
14 * initial version May 15, 2014 <br>
15 * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
16 */
17 public class AngleSolidUnit extends LinearUnit<AngleSolidUnit>
18 {
19 /** */
20 private static final long serialVersionUID = 20140607L;
21
22 /** The SI unit for solid angle is steradian. */
23 public static final AngleSolidUnit SI;
24
25 /** steradian. */
26 public static final AngleSolidUnit STERADIAN;
27
28 /** square degree. */
29 public static final AngleSolidUnit SQUARE_DEGREE;
30
31 static
32 {
33 SI = new AngleSolidUnit("AngleSolidUnit.steradian", "AngleSolidUnit.sr", SI_DERIVED);
34 STERADIAN = SI;
35 SQUARE_DEGREE = new AngleSolidUnit("AngleSolidUnit.square_degree", "AngleSolidUnit.sq_deg", SI_DERIVED, STERADIAN,
36 (Math.PI / 180.0) * (Math.PI / 180.0), true);
37 }
38
39 /**
40 * Build a standard unit.
41 * @param nameKey String; the key to the locale file for the long name of the unit
42 * @param abbreviationKey String; the key to the locale file for the abbreviation of the unit
43 * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
44 */
45 private AngleSolidUnit(final String nameKey, final String abbreviationKey, final UnitSystem unitSystem)
46 {
47 super(nameKey, abbreviationKey, unitSystem, true);
48 }
49
50 /**
51 * Construct a derived unit as a conversion from another unit.
52 * @param nameOrNameKey String; if standardUnit: the key to the locale file for the long name of the unit, otherwise the
53 * name itself
54 * @param abbreviationOrAbbreviationKey String; if standardUnit: the key to the locale file for the abbreviation of the
55 * unit, otherwise the abbreviation itself
56 * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
57 * @param referenceUnit AngleSolidUnit; the unit to convert to
58 * @param scaleFactorToReferenceUnit double; multiply a value in this unit by the factor to convert to the given reference
59 * unit
60 * @param standardUnit boolean; indicates whether it is a standard unit with a definition in the locale, or a user-defined
61 * unit
62 */
63 private AngleSolidUnit(final String nameOrNameKey, final String abbreviationOrAbbreviationKey, final UnitSystem unitSystem,
64 final AngleSolidUnit referenceUnit, final double scaleFactorToReferenceUnit, final boolean standardUnit)
65 {
66 super(nameOrNameKey, abbreviationOrAbbreviationKey, unitSystem, referenceUnit, scaleFactorToReferenceUnit,
67 standardUnit);
68 }
69
70 /**
71 * Build a user-defined unit with a conversion factor to another unit.
72 * @param name String; the long name of the unit
73 * @param abbreviation String; the abbreviation of the unit
74 * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
75 * @param referenceUnit AngleSolidUnit; the unit to convert to
76 * @param scaleFactorToReferenceUnit double; multiply a value in this unit by the factor to convert to the given reference
77 * unit
78 */
79 public AngleSolidUnit(final String name, final String abbreviation, final UnitSystem unitSystem,
80 final AngleSolidUnit referenceUnit, final double scaleFactorToReferenceUnit)
81 {
82 this(name, abbreviation, unitSystem, referenceUnit, scaleFactorToReferenceUnit, false);
83 }
84
85 /** {@inheritDoc} */
86 @Override
87 public final AngleSolidUnit getStandardUnit()
88 {
89 return STERADIAN;
90 }
91
92 /** {@inheritDoc} */
93 @Override
94 public final String getSICoefficientsString()
95 {
96 return "1";
97 }
98
99 }