| 1 | /* |
| 2 | * JScience - Java(TM) Tools and Libraries for the Advancement of Sciences. |
| 3 | * Copyright (C) 2007 - JScience (http://jscience.org/) |
| 4 | * All rights reserved. |
| 5 | * |
| 6 | * Permission to use, copy, modify, and distribute this software is |
| 7 | * freely granted, provided that this notice is preserved. |
| 8 | */ |
| 9 | package javax.measure; |
| 10 | |
| 11 | import java.io.Serializable; |
| 12 | import java.math.BigDecimal; |
| 13 | import java.math.MathContext; |
| 14 | |
| 15 | import javax.measure.quantity.Quantity; |
| 16 | import javax.measure.unit.CompoundUnit; |
| 17 | import javax.measure.unit.Unit; |
| 18 | |
| 19 | /** |
| 20 | * <p> This class represents the result of a measurement stated in a |
| 21 | * known unit.</p> |
| 22 | * |
| 23 | * <p> There is no constraint upon the measurement value itself: scalars, |
| 24 | * vectors, or even data sets are valid values as long as |
| 25 | * an aggregate magnitude can be determined (see {@link Measurable}).</p> |
| 26 | * |
| 27 | * @author <a href="mailto:jean-marie@dautelle.com">Jean-Marie Dautelle</a> |
| 28 | * @version 4.2, August 26, 2007 |
| 29 | */ |
| 30 | public abstract class Measure<V, Q extends Quantity> implements Measurable<Q>, |
| 31 | Serializable { |
| 32 | |
| 33 | /** |
| 34 | * Default constructor. |
| 35 | */ |
| 36 | protected Measure() { |
| 37 | } |
| 38 | |
| 39 | /** |
| 40 | * Returns the scalar measure for the specified <code>double</code> |
| 41 | * stated in the specified unit. |
| 42 | * |
| 43 | * @param doubleValue the measurement value. |
| 44 | * @param unit the measurement unit. |
| 45 | */ |
| 46 | public static <Q extends Quantity> Measure<java.lang.Double, Q> valueOf( |
| 47 | double doubleValue, Unit<Q> unit) { |
| 48 | return new Double<Q>(doubleValue, unit); |
| 49 | } |
| 50 | |
| 51 | /** |
| 52 | * Returns the scalar measure for the specified <code>double</code> |
| 53 | * stated in the specified unit. |
| 54 | * |
| 55 | * @param longValue the measurement value. |
| 56 | * @param unit the measurement unit. |
| 57 | */ |
| 58 | public static <Q extends Quantity> Measure<java.lang.Long, Q> valueOf( |
| 59 | long longValue, Unit<Q> unit) { |
| 60 | return new Long<Q>(longValue, unit); |
| 61 | } |
| 62 | |
| 63 | /** |
| 64 | * Returns the scalar measure for the specified <code>float</code> |
| 65 | * stated in the specified unit. |
| 66 | * |
| 67 | * @param floatValue the measurement value. |
| 68 | * @param unit the measurement unit. |
| 69 | */ |
| 70 | public static <Q extends Quantity> Measure<java.lang.Float, Q> valueOf( |
| 71 | float floatValue, Unit<Q> unit) { |
| 72 | return new Float<Q>(floatValue, unit); |
| 73 | } |
| 74 | |
| 75 | /** |
| 76 | * Returns the scalar measure for the specified <code>int</code> |
| 77 | * stated in the specified unit. |
| 78 | * |
| 79 | * @param intValue the measurement value. |
| 80 | * @param unit the measurement unit. |
| 81 | */ |
| 82 | public static <Q extends Quantity> Measure<java.lang.Integer, Q> valueOf( |
| 83 | int intValue, Unit<Q> unit) { |
| 84 | return new Integer<Q>(intValue, unit); |
| 85 | } |
| 86 | |
| 87 | /** |
| 88 | * Returns the measurement value of this measure. |
| 89 | * |
| 90 | * @return the measurement value. |
| 91 | */ |
| 92 | public abstract V getValue(); |
| 93 | |
| 94 | /** |
| 95 | * Returns the measurement unit of this measure. |
| 96 | * |
| 97 | * @return the measurement unit. |
| 98 | */ |
| 99 | public abstract Unit<Q> getUnit(); |
| 100 | |
| 101 | /** |
| 102 | * Returns the measure equivalent to this measure but stated in the |
| 103 | * specified unit. This method may result in lost of precision |
| 104 | * (e.g. measure of integral value). |
| 105 | * |
| 106 | * @param unit the new measurement unit. |
| 107 | * @return the measure stated in the specified unit. |
| 108 | */ |
| 109 | public abstract Measure<V, Q> to(Unit<Q> unit); |
| 110 | |
| 111 | /** |
| 112 | * Returns the value of this measure stated in the specified unit as |
| 113 | * a <code>double</code>. If the measure has too great a magnitude to |
| 114 | * be represented as a <code>double</code>, it will be converted to |
| 115 | * <code>Double.NEGATIVE_INFINITY</code> or |
| 116 | * <code>Double.POSITIVE_INFINITY</code> as appropriate. |
| 117 | * |
| 118 | * @param unit the unit in which this measure is stated. |
| 119 | * @return the numeric value after conversion to type <code>double</code>. |
| 120 | */ |
| 121 | public abstract double doubleValue(Unit<Q> unit); |
| 122 | |
| 123 | /** |
| 124 | * Returns the estimated integral value of this measure stated in |
| 125 | * the specified unit as a <code>long</code>. |
| 126 | * |
| 127 | * <p> Note: This method differs from the <code>Number.longValue()</code> |
| 128 | * in the sense that the closest integer value is returned |
| 129 | * and an ArithmeticException is raised instead |
| 130 | * of a bit truncation in case of overflow (safety critical).</p> |
| 131 | * |
| 132 | * @param unit the unit in which the measurable value is stated. |
| 133 | * @return the numeric value after conversion to type <code>long</code>. |
| 134 | * @throws ArithmeticException if this quantity cannot be represented |
| 135 | * as a <code>long</code> number in the specified unit. |
| 136 | */ |
| 137 | public long longValue(Unit<Q> unit) throws ArithmeticException { |
| 138 | double doubleValue = doubleValue(unit); |
| 139 | if (java.lang.Double.isNaN(doubleValue) |
| 140 | || (doubleValue < java.lang.Long.MIN_VALUE) |
| 141 | || (doubleValue > java.lang.Long.MAX_VALUE)) |
| 142 | throw new ArithmeticException(doubleValue + " " + unit |
| 143 | + " cannot be represented as long"); |
| 144 | return Math.round(doubleValue); |
| 145 | } |
| 146 | |
| 147 | /** |
| 148 | * Returns the value of this measure stated in the specified unit as a |
| 149 | * <code>float</code>. If the measure has too great a magnitude to be |
| 150 | * represented as a <code>float</code>, it will be converted to |
| 151 | * <code>Float.NEGATIVE_INFINITY</code> or |
| 152 | * <code>Float.POSITIVE_INFINITY</code> as appropriate. |
| 153 | * |
| 154 | * @param unit the unit in which the measure is stated. |
| 155 | * @return the numeric value after conversion to type <code>float</code>. |
| 156 | */ |
| 157 | public float floatValue(Unit<Q> unit) { |
| 158 | return (float) doubleValue(unit); |
| 159 | } |
| 160 | |
| 161 | /** |
| 162 | * Returns the estimated integral value of this measure stated in |
| 163 | * the specified unit as a <code>int</code>. |
| 164 | * |
| 165 | * <p> Note: This method differs from the <code>Number.intValue()</code> |
| 166 | * in the sense that the closest integer value is returned |
| 167 | * and an ArithmeticException is raised instead |
| 168 | * of a bit truncation in case of overflow (safety critical).</p> |
| 169 | * |
| 170 | * @param unit the unit in which the measurable value is stated. |
| 171 | * @return the numeric value after conversion to type <code>int</code>. |
| 172 | * @throws ArithmeticException if this quantity cannot be represented |
| 173 | * as a <code>int</code> number in the specified unit. |
| 174 | */ |
| 175 | public int intValue(Unit<Q> unit) { |
| 176 | long longValue = longValue(unit); |
| 177 | if ((longValue > java.lang.Integer.MAX_VALUE) |
| 178 | || (longValue < java.lang.Integer.MIN_VALUE)) |
| 179 | throw new ArithmeticException("Overflow"); |
| 180 | return (int) longValue; |
| 181 | } |
| 182 | |
| 183 | /** |
| 184 | * Compares this measure against the specified object for |
| 185 | * strict equality (same unit and amount). |
| 186 | * To compare measures stated using different units the |
| 187 | * {@link #compareTo} method should be used. |
| 188 | * |
| 189 | * @param obj the object to compare with. |
| 190 | * @return <code>true</code> if both objects are identical (same |
| 191 | * unit and same amount); <code>false</code> otherwise. |
| 192 | */ |
| 193 | @SuppressWarnings("unchecked") |
| 194 | public boolean equals(Object obj) { |
| 195 | if (!(obj instanceof Measure)) |
| 196 | return false; |
| 197 | Measure that = (Measure) obj; |
| 198 | return this.getUnit().equals(that.getUnit()) |
| 199 | && this.getValue().equals(that.getValue()); |
| 200 | } |
| 201 | |
| 202 | /** |
| 203 | * Returns the hash code for this scalar. |
| 204 | * |
| 205 | * @return the hash code value. |
| 206 | */ |
| 207 | public int hashCode() { |
| 208 | return getUnit().hashCode() + getValue().hashCode(); |
| 209 | } |
| 210 | |
| 211 | /** |
| 212 | * Returns the <code>String</code> representation of this measure |
| 213 | * The string produced for a given measure is always the same; |
| 214 | * it is not affected by locale. This means that it can be used |
| 215 | * as a canonical string representation for exchanging data, |
| 216 | * or as a key for a Hashtable, etc. Locale-sensitive |
| 217 | * measure formatting and parsing is handled by the {@link |
| 218 | * MeasureFormat} class and its subclasses. |
| 219 | * |
| 220 | * @return the string representation of this measure. |
| 221 | */ |
| 222 | public String toString() { |
| 223 | if (getUnit() instanceof CompoundUnit) |
| 224 | return MeasureFormat.DEFAULT.formatCompound(doubleValue(getUnit()), |
| 225 | getUnit(), new StringBuffer(), null).toString(); |
| 226 | return getValue() + " " + getUnit(); |
| 227 | } |
| 228 | |
| 229 | /** |
| 230 | * Compares this measure to the specified measurable quantity. |
| 231 | * This method compares the {@link Measurable#doubleValue(Unit)} of |
| 232 | * both this measure and the specified measurable stated in the |
| 233 | * same unit (this measure's {@link #getUnit() unit}). |
| 234 | * |
| 235 | * @return a negative integer, zero, or a positive integer as this measure |
| 236 | * is less than, equal to, or greater than the specified measurable |
| 237 | * quantity. |
| 238 | * @return <code>Double.compare(this.doubleValue(getUnit()), |
| 239 | * that.doubleValue(getUnit()))</code> |
| 240 | */ |
| 241 | public int compareTo(Measurable<Q> that) { |
| 242 | return java.lang.Double.compare(doubleValue(getUnit()), that |
| 243 | .doubleValue(getUnit())); |
| 244 | } |
| 245 | |
| 246 | /** |
| 247 | * Holds scalar implementation for <code>double</code> values. |
| 248 | */ |
| 249 | private static final class Double<Q extends Quantity> extends |
| 250 | Measure<java.lang.Double, Q> { |
| 251 | |
| 252 | private final double _value; |
| 253 | |
| 254 | private final Unit<Q> _unit; |
| 255 | |
| 256 | public Double(double value, Unit<Q> unit) { |
| 257 | _value = value; |
| 258 | _unit = unit; |
| 259 | } |
| 260 | |
| 261 | @Override |
| 262 | public Unit<Q> getUnit() { |
| 263 | return _unit; |
| 264 | } |
| 265 | |
| 266 | @Override |
| 267 | public java.lang.Double getValue() { |
| 268 | return _value; |
| 269 | } |
| 270 | |
| 271 | @Override |
| 272 | public Measure<java.lang.Double, Q> to(Unit<Q> unit) { |
| 273 | if ((unit == _unit) || (unit.equals(_unit))) |
| 274 | return this; |
| 275 | return new Double<Q>(doubleValue(unit), unit); |
| 276 | } |
| 277 | |
| 278 | public double doubleValue(Unit<Q> unit) { |
| 279 | if ((unit == _unit) || (unit.equals(_unit))) |
| 280 | return _value; |
| 281 | return _unit.getConverterTo(unit).convert(_value); |
| 282 | } |
| 283 | |
| 284 | private static final long serialVersionUID = 1L; |
| 285 | } |
| 286 | |
| 287 | /** |
| 288 | * Holds scalar implementation for <code>long</code> values. |
| 289 | */ |
| 290 | private static final class Long<Q extends Quantity> extends |
| 291 | Measure<java.lang.Long, Q> { |
| 292 | |
| 293 | private final long _value; |
| 294 | |
| 295 | private final Unit<Q> _unit; |
| 296 | |
| 297 | public Long(long value, Unit<Q> unit) { |
| 298 | _value = value; |
| 299 | _unit = unit; |
| 300 | } |
| 301 | |
| 302 | @Override |
| 303 | public Unit<Q> getUnit() { |
| 304 | return _unit; |
| 305 | } |
| 306 | |
| 307 | @Override |
| 308 | public java.lang.Long getValue() { |
| 309 | return _value; |
| 310 | } |
| 311 | |
| 312 | @Override |
| 313 | public Measure<java.lang.Long, Q> to(Unit<Q> unit) { |
| 314 | if ((unit == _unit) || (unit.equals(_unit))) |
| 315 | return this; |
| 316 | return new Long<Q>(longValue(unit), unit); |
| 317 | } |
| 318 | |
| 319 | public double doubleValue(Unit<Q> unit) { |
| 320 | if ((unit == _unit) || (unit.equals(_unit))) |
| 321 | return _value; |
| 322 | return _unit.getConverterTo(unit).convert(_value); |
| 323 | } |
| 324 | |
| 325 | public long longValue(Unit<Q> unit) throws ArithmeticException { |
| 326 | if ((unit == _unit) || (unit.equals(_unit))) |
| 327 | return _value; // No conversion, returns value directly. |
| 328 | return super.longValue(unit); |
| 329 | } |
| 330 | |
| 331 | private static final long serialVersionUID = 1L; |
| 332 | |
| 333 | } |
| 334 | |
| 335 | /** |
| 336 | * Holds scalar implementation for <code>float</code> values. |
| 337 | */ |
| 338 | private static final class Float<Q extends Quantity> extends |
| 339 | Measure<java.lang.Float, Q> { |
| 340 | |
| 341 | private final float _value; |
| 342 | |
| 343 | private final Unit<Q> _unit; |
| 344 | |
| 345 | public Float(float value, Unit<Q> unit) { |
| 346 | _value = value; |
| 347 | _unit = unit; |
| 348 | } |
| 349 | |
| 350 | @Override |
| 351 | public Unit<Q> getUnit() { |
| 352 | return _unit; |
| 353 | } |
| 354 | |
| 355 | @Override |
| 356 | public java.lang.Float getValue() { |
| 357 | return _value; |
| 358 | } |
| 359 | |
| 360 | @Override |
| 361 | public Measure<java.lang.Float, Q> to(Unit<Q> unit) { |
| 362 | if ((unit == _unit) || (unit.equals(_unit))) |
| 363 | return this; |
| 364 | return new Float<Q>(floatValue(unit), unit); |
| 365 | } |
| 366 | |
| 367 | public double doubleValue(Unit<Q> unit) { |
| 368 | if ((unit == _unit) || (unit.equals(_unit))) |
| 369 | return _value; |
| 370 | return _unit.getConverterTo(unit).convert(_value); |
| 371 | } |
| 372 | |
| 373 | private static final long serialVersionUID = 1L; |
| 374 | } |
| 375 | |
| 376 | /** |
| 377 | * Holds scalar implementation for <code>long</code> values. |
| 378 | */ |
| 379 | private static final class Integer<Q extends Quantity> extends |
| 380 | Measure<java.lang.Integer, Q> { |
| 381 | |
| 382 | private final int _value; |
| 383 | |
| 384 | private final Unit<Q> _unit; |
| 385 | |
| 386 | public Integer(int value, Unit<Q> unit) { |
| 387 | _value = value; |
| 388 | _unit = unit; |
| 389 | } |
| 390 | |
| 391 | @Override |
| 392 | public Unit<Q> getUnit() { |
| 393 | return _unit; |
| 394 | } |
| 395 | |
| 396 | @Override |
| 397 | public java.lang.Integer getValue() { |
| 398 | return _value; |
| 399 | } |
| 400 | |
| 401 | @Override |
| 402 | public Measure<java.lang.Integer, Q> to(Unit<Q> unit) { |
| 403 | if ((unit == _unit) || (unit.equals(_unit))) |
| 404 | return this; |
| 405 | return new Integer<Q>(intValue(unit), unit); |
| 406 | } |
| 407 | |
| 408 | public double doubleValue(Unit<Q> unit) { |
| 409 | if ((unit == _unit) || (unit.equals(_unit))) |
| 410 | return _value; |
| 411 | return _unit.getConverterTo(unit).convert(_value); |
| 412 | } |
| 413 | |
| 414 | public long longValue(Unit<Q> unit) throws ArithmeticException { |
| 415 | if ((unit == _unit) || (unit.equals(_unit))) |
| 416 | return _value; // No conversion, returns value directly. |
| 417 | return super.longValue(unit); |
| 418 | } |
| 419 | |
| 420 | private static final long serialVersionUID = 1L; |
| 421 | |
| 422 | } |
| 423 | |
| 424 | /** |
| 425 | * @deprecated {@link DecimalMeasure} should be used directly. |
| 426 | */ |
| 427 | public static <Q extends Quantity> Measure<BigDecimal, Q> valueOf( |
| 428 | BigDecimal decimal, Unit<Q> unit) { |
| 429 | return DecimalMeasure.valueOf(decimal, unit); |
| 430 | } |
| 431 | |
| 432 | /** |
| 433 | * @deprecated {@link DecimalMeasure} should be used directly and |
| 434 | * <code>MathContext</code> specified explicitly when |
| 435 | * {@link DecimalMeasure#to(Unit, MathContext) converting}. |
| 436 | */ |
| 437 | public static <Q extends Quantity> Measure<BigDecimal, Q> valueOf( |
| 438 | BigDecimal decimal, Unit<Q> unit, MathContext mathContext) { |
| 439 | return DecimalMeasure.valueOf(decimal, unit); |
| 440 | } |
| 441 | |
| 442 | /** |
| 443 | * @deprecated {@link VectorMeasure} should be used directly. |
| 444 | */ |
| 445 | public static <Q extends Quantity> Measure<double[], Q> valueOf( |
| 446 | double[] components, Unit<Q> unit) { |
| 447 | return VectorMeasure.valueOf(components, unit); |
| 448 | } |
| 449 | } |