1 package org.djunits.unit;
2
3 import org.djunits.unit.scale.LinearScale;
4 import org.djunits.unit.scale.Scale;
5 import org.djunits.unit.scale.StandardScale;
6 import org.djunits.unit.unitsystem.UnitSystem;
7
8 /**
9 * A linear unit with easy-access constructor with a linear factor, and access to the linear factor. <br>
10 * A linear unit is a unit that is linearly related to the SI standard unit. E.g. Mile is linearly related to meter (the SI unit
11 * for length). Unlike temperature in degrees Celsius which is <strong>not</strong> linearly related to the Kelvin (the SI unit
12 * for temperature).
13 * <p>
14 * Copyright (c) 2013-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
15 * BSD-style license. See <a href="http://opentrafficsim.org/docs/license.html">OpenTrafficSim License</a>.
16 * </p>
17 * $LastChangedDate: 2015-07-24 02:58:59 +0200 (Fri, 24 Jul 2015) $, @version $Revision: 1147 $, by $Author: averbraeck $,
18 * initial version Oct 11, 2015 <br>
19 * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
20 * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
21 * @param <U> the linear Unit.
22 */
23 public abstract class LinearUnit<U extends LinearUnit<U>> extends Unit<U>
24 {
25 /** */
26 private static final long serialVersionUID = 20151011L;
27
28 /**
29 * Build a standard linear unit and create the fields for a unit. If the parameter standardUnit is true, it is a standard
30 * unit where name is the nameKey, and abbreviation is the abbreviationKey; if false, this unit is a user-defined unit where
31 * the localization files do not have an entry. If standardUnit is true, a UnitException is silently ignored; if
32 * standardUnit is false a UnitException is thrown as a RunTimeException.
33 * @param nameOrNameKey String; if standardUnit: the key to the locale file for the long name of the unit, otherwise the
34 * name itself
35 * @param abbreviationOrAbbreviationKey String; if standardUnit: the key to the locale file for the abbreviation of the
36 * unit, otherwise the abbreviation itself
37 * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
38 * @param standardUnit boolean; indicates whether it is a standard unit with a definition in the locale, or a user-defined
39 * unit
40 */
41 public LinearUnit(final String nameOrNameKey, final String abbreviationOrAbbreviationKey, final UnitSystem unitSystem,
42 final boolean standardUnit)
43 {
44 super(nameOrNameKey, abbreviationOrAbbreviationKey, unitSystem, standardUnit);
45 }
46
47 /**
48 * Build a unit with a linear conversion factor to another unit. If the parameter standardUnit is true, it is a standard
49 * unit where name is the nameKey, and abbreviation is the abbreviationKey; if false, this unit is a user-defined unit where
50 * the localization files do not have an entry. If standardUnit is true, a UnitException is silently ignored; if
51 * standardUnit is false a UnitException is thrown as a RunTimeException.
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 U; 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 protected LinearUnit(final String nameOrNameKey, final String abbreviationOrAbbreviationKey, final UnitSystem unitSystem,
64 final U referenceUnit, final double scaleFactorToReferenceUnit, final boolean standardUnit)
65 {
66 super(nameOrNameKey, abbreviationOrAbbreviationKey, unitSystem,
67 referenceUnit == null ? StandardScale.SCALE
68 : new LinearScale(
69 referenceUnit.getScale().getConversionFactorToStandardUnit() * scaleFactorToReferenceUnit),
70 standardUnit);
71 }
72
73 /**
74 * Build a unit with a specific conversion scale to/from the standard unit. If the parameter standardUnit is true, it is a
75 * standard unit where name is the nameKey, and abbreviation is the abbreviationKey; if false, this unit is a user-defined
76 * unit where the localization files do not have an entry. If standardUnit is true, a UnitException is silently ignored; if
77 * standardUnit is false a UnitException is thrown as a RunTimeException.
78 * @param nameOrNameKey String; if standardUnit: the key to the locale file for the long name of the unit, otherwise the
79 * name itself
80 * @param abbreviationOrAbbreviationKey String; if standardUnit: the key to the locale file for the abbreviation of the
81 * unit, otherwise the abbreviation itself
82 * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
83 * @param scale Scale; the conversion scale to use for this unit
84 * @param standardUnit boolean; indicates whether it is a standard unit with a definition in the locale, or a user-defined
85 * unit
86 */
87 protected LinearUnit(final String nameOrNameKey, final String abbreviationOrAbbreviationKey, final UnitSystem unitSystem,
88 final Scale scale, final boolean standardUnit)
89 {
90 super(nameOrNameKey, abbreviationOrAbbreviationKey, unitSystem, scale, standardUnit);
91 }
92
93 /** {@inheritDoc} */
94 @Override
95 @SuppressWarnings("checkstyle:designforextension")
96 public LinearScale getScale()
97 {
98 return (LinearScale) super.getScale();
99 }
100
101 /**
102 * @return the conversion factor to the standard unit (e.g., the SI unit)
103 */
104 public final double getScaleFactor()
105 {
106 return getScale().getConversionFactorToStandardUnit();
107 }
108
109 /** {@inheritDoc} */
110 @Override
111 public int hashCode()
112 {
113 final int prime = 31;
114 int result = super.hashCode();
115 long temp;
116 temp = Double.doubleToLongBits(this.getScaleFactor());
117 result = prime * result + (int) (temp ^ (temp >>> 32));
118 return result;
119 }
120
121 /** {@inheritDoc} */
122 @SuppressWarnings("checkstyle:needbraces")
123 @Override
124 public boolean equals(final Object obj)
125 {
126 if (this == obj)
127 return true;
128 if (!super.equals(obj))
129 return false;
130 if (getClass() != obj.getClass())
131 return false;
132 LinearUnit<?> other = (LinearUnit<?>) obj;
133 if (Double.doubleToLongBits(this.getScaleFactor()) != Double.doubleToLongBits(other.getScaleFactor()))
134 return false;
135 return true;
136 }
137
138 /** {@inheritDoc} */
139 @SuppressWarnings("checkstyle:needbraces")
140 @Override
141 public boolean equalsIgnoreNaming(final Object obj)
142 {
143 if (this == obj)
144 return true;
145 if (getClass() != obj.getClass())
146 return false;
147 LinearUnit<?> other = (LinearUnit<?>) obj;
148 if (Double.doubleToLongBits(getScaleFactor()) != Double.doubleToLongBits(other.getScaleFactor()))
149 return false;
150 return true;
151 }
152
153 }