001/* 002 * Units of Measurement Reference Implementation 003 * Copyright (c) 2005-2017, Jean-Marie Dautelle, Werner Keil, V2COM. 004 * 005 * All rights reserved. 006 * 007 * Redistribution and use in source and binary forms, with or without modification, 008 * are permitted provided that the following conditions are met: 009 * 010 * 1. Redistributions of source code must retain the above copyright notice, 011 * this list of conditions and the following disclaimer. 012 * 013 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions 014 * and the following disclaimer in the documentation and/or other materials provided with the distribution. 015 * 016 * 3. Neither the name of JSR-363 nor the names of its contributors may be used to endorse or promote products 017 * derived from this software without specific prior written permission. 018 * 019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 020 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 021 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 022 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE 023 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 026 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 028 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 029 */ 030package tec.units.ri.unit; 031 032import java.util.Map; 033 034import javax.measure.Dimension; 035import javax.measure.Quantity; 036import javax.measure.Unit; 037import javax.measure.UnitConverter; 038 039import tec.units.ri.AbstractUnit; 040import tec.uom.lib.common.function.UnitConverterSupplier; 041 042/** 043 * <p> 044 * This class represents the units derived from other units using {@linkplain UnitConverter converters}. 045 * </p> 046 * 047 * <p> 048 * Examples of transformed units:<code> 049 * CELSIUS = KELVIN.shift(273.15); 050 * FOOT = METRE.multiply(3048).divide(10000); 051 * MILLISECOND = MILLI(SECOND); 052 * </code> 053 * </p> 054 * 055 * <p> 056 * Transformed units have no symbol. But like all other units, they may have labels attached to them (see 057 * {@link javax.measure.format.UnitFormat#label(Unit, String)} 058 * </p> 059 * 060 * <p> 061 * Instances of this class are created through the {@link AbstractUnit#transform} method. 062 * </p> 063 * 064 * @param <Q> 065 * The type of the quantity measured by this unit. 066 * 067 * @author <a href="mailto:jean-marie@dautelle.com">Jean-Marie Dautelle</a> 068 * @author <a href="mailto:units@catmedia.us">Werner Keil</a> 069 * @version 1.0.2, June 7, 2017 070 * @since 1.0 071 */ 072public final class TransformedUnit<Q extends Quantity<Q>> extends AbstractUnit<Q> implements UnitConverterSupplier { 073 074 /** 075 * 076 */ 077 // private static final long serialVersionUID = 1L; 078 079 /** 080 * Holds the parent unit. 081 */ 082 private final AbstractUnit<Q> parentUnit; 083 084 /** 085 * Holds the system unit. 086 */ 087 private final Unit<Q> systemUnit; 088 089 /** 090 * Holds the converter to the parent unit. 091 */ 092 private final UnitConverter converter; 093 094 /** 095 * Holds the symbol. 096 */ 097 private String symbol; 098 099 /** 100 * Creates a transformed unit from the specified parent and system unit. using the parent as symbol 101 * 102 * @param parentUnit 103 * the parent unit from which this unit is derived. 104 * @param sysUnit 105 * the system unit which this unit is based on. 106 * @param converter 107 * the converter to the parent units. 108 */ 109 public TransformedUnit(String symbol, Unit<Q> parentUnit, Unit<Q> sysUnit, UnitConverter unitConverter) { 110 if (parentUnit instanceof AbstractUnit) { 111 final AbstractUnit<Q> abParent = (AbstractUnit<Q>) parentUnit; 112 113 this.systemUnit = sysUnit; 114 // if (!abParent.isSystemUnit()) { 115 // throw new IllegalArgumentException("The parent unit: " + abParent 116 // + " is not a system unit"); 117 // } 118 this.parentUnit = abParent; 119 this.converter = unitConverter; 120 this.symbol = symbol; 121 // this.symbol = symbol; //TODO see 122 // https://github.com/unitsofmeasurement/uom-se/issues/54 123 } else { 124 throw new IllegalArgumentException("The parent unit: " + parentUnit + " is not an abstract unit."); 125 } 126 } 127 128 /** 129 * Creates a transformed unit from the specified parent unit. 130 * 131 * @param parentUnit 132 * the system unit from which this unit is derived. 133 * @param unitConverter 134 * the converter to the parent units. 135 */ 136 public TransformedUnit(AbstractUnit<Q> parentUnit, UnitConverter unitConverter) { 137 this(null, parentUnit, unitConverter); 138 } 139 140 /** 141 * Creates a transformed unit from the specified parent unit. 142 * 143 * @param symbol 144 * the symbol to use with this transformed unit. 145 * @param parentUnit 146 * the parent unit from which this unit is derived. 147 * @param unitConverter 148 * the converter to the parent units. 149 */ 150 public TransformedUnit(String symbol, Unit<Q> parentUnit, UnitConverter unitConverter) { 151 this(null, parentUnit, parentUnit.getSystemUnit(), unitConverter); 152 } 153 154 /** 155 * Creates a transformed unit from the specified system unit. 156 * 157 * @param parentUnit 158 * the system unit from which this unit is derived. 159 * @param toParentUnit 160 * the converter to the parent units. 161 * @throws IllegalArgumentException 162 * if the specified parent unit is not an {@link AbstractUnit#isSystemUnit() system unit} 163 * @throws ClassCastException 164 * if parentUnit is not a valid {@link Unit} implementation 165 */ 166 public TransformedUnit(Unit<Q> parentUnit, UnitConverter toParentUnit) { 167 this((AbstractUnit<Q>) parentUnit, toParentUnit); 168 } 169 170 @Override 171 public Dimension getDimension() { 172 return parentUnit.getDimension(); 173 } 174 175 @Override 176 public UnitConverter getSystemConverter() { 177 return parentUnit.getSystemConverter().concatenate(converter); 178 } 179 180 @Override 181 public AbstractUnit<Q> toSystemUnit() { 182 return parentUnit.getSystemUnit(); 183 } 184 185 @Override 186 public Map<? extends Unit<?>, Integer> getBaseUnits() { 187 return parentUnit.getBaseUnits(); 188 } 189 190 @Override 191 public int hashCode() { 192 return parentUnit.hashCode() + converter.hashCode(); 193 } 194 195 @Override 196 public boolean equals(Object that) { 197 if (this == that) 198 return true; 199 if (!(that instanceof TransformedUnit)) 200 return false; 201 TransformedUnit<?> thatUnit = (TransformedUnit<?>) that; 202 return this.parentUnit.equals(thatUnit.parentUnit) && this.converter.equals(thatUnit.converter); 203 } 204 205 @Override 206 // TODO clarify JavaDoc or adjust to what the Unit JavaDoc says. 207 public String getSymbol() { 208 if (super.getSymbol() != null) { 209 return super.getSymbol(); 210 } 211 return symbol; 212 } 213 214 /** 215 * Returns the parent unit for this unit. The parent unit is the untransformed unit from which this unit is derived. 216 * 217 * @return the untransformed unit from which this unit is derived. 218 */ 219 public Unit<Q> getParentUnit() { 220 return parentUnit; 221 } 222 223 /** 224 * Returns the converter to the parent unit. 225 * 226 * @return the converter to the parent unit. 227 */ 228 @Override 229 public UnitConverter getConverter() { 230 return converter; 231 } 232}