package org.djunits.unit;
   
   import static org.djunits.unit.unitsystem.UnitSystem.CGS;
   import static org.djunits.unit.unitsystem.UnitSystem.IMPERIAL;
   import static org.djunits.unit.unitsystem.UnitSystem.MTS;
   import static org.djunits.unit.unitsystem.UnitSystem.OTHER;
   import static org.djunits.unit.unitsystem.UnitSystem.SI_DERIVED;
   
   import org.djunits.unit.unitsystem.UnitSystem;
  
  /**
   * The units of power.
   * <p>
   * Copyright (c) 2015-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
   * BSD-style license. See <a href="http://djunits.org/docs/license.html">DJUNITS License</a>.
   * <p>
   * $LastChangedDate: 2019-01-18 00:35:01 +0100 (Fri, 18 Jan 2019) $, @version $Revision: 324 $, by $Author: averbraeck $,
   * initial version May 15, 2014 <br>
   * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
   */
  public class PowerUnit extends LinearUnit<PowerUnit>
  {
      /** */
      private static final long serialVersionUID = 20140607L;
  
      /** the unit of mass for the power unit, e.g., kilogram. */
      private final MassUnit massUnit;
  
      /** the unit of length for the power unit, e.g., length. */
      private final LengthUnit lengthUnit;
  
      /** the unit of time for the power unit, e.g., second. */
      private final DurationUnit durationUnit;
  
      /** The SI unit for power is watt. */
      public static final PowerUnit SI;
  
      /** femtowatt. */
      public static final PowerUnit FEMTOWATT;
  
      /** picowatt. */
      public static final PowerUnit PICOWATT;
  
      /** nanowatt. */
      public static final PowerUnit NANOWATT;
  
      /** microwatt. */
      public static final PowerUnit MICROWATT;
  
      /** milliwatt. */
      public static final PowerUnit MILLIWATT;
  
      /** watt. */
      public static final PowerUnit WATT;
  
      /** kiloawatt. */
      public static final PowerUnit KILOWATT;
  
      /** megawatt. */
      public static final PowerUnit MEGAWATT;
  
      /** gigawatt. */
      public static final PowerUnit GIGAWATT;
  
      /** terawatt. */
      public static final PowerUnit TERAWATT;
  
      /** petawatt. */
      public static final PowerUnit PETAWATT;
  
      /** foot-pound-force per hour. */
      public static final PowerUnit FOOT_POUND_FORCE_PER_HOUR;
  
      /** foot-pound-force per minute. */
      public static final PowerUnit FOOT_POUND_FORCE_PER_MINUTE;
  
      /** foot-pound-force per second. */
      public static final PowerUnit FOOT_POUND_FORCE_PER_SECOND;
  
      /** horsepower (metric). */
      public static final PowerUnit HORSEPOWER_METRIC;
  
      /** sthene-meter per second. */
      public static final PowerUnit STHENE_METER_PER_SECOND;
  
      /** erg per second. */
      public static final PowerUnit ERG_PER_SECOND;
  
      static
      {
          SI = new PowerUnit(MassUnit.KILOGRAM, LengthUnit.METER, DurationUnit.SECOND, "PowerUnit.watt", "PowerUnit.W",
                  SI_DERIVED, true);
          WATT = SI;
          FEMTOWATT = new PowerUnit("PowerUnit.femtowatt", "PowerUnit.fW", SI_DERIVED, WATT, 1.0E-15, true);
          PICOWATT = new PowerUnit("PowerUnit.picowatt", "PowerUnit.pW", SI_DERIVED, WATT, 1.0E-12, true);
          NANOWATT = new PowerUnit("PowerUnit.nanowatt", "PowerUnit.nW", SI_DERIVED, WATT, 1.0E-9, true);
          MICROWATT = new PowerUnit("PowerUnit.microwatt", "PowerUnit.muW", SI_DERIVED, WATT, 1.0E-6, true);
          MILLIWATT = new PowerUnit("PowerUnit.milliwatt", "PowerUnit.mW", SI_DERIVED, WATT, 1.0E-3, true);
          KILOWATT = new PowerUnit("PowerUnit.kilowatt", "PowerUnit.kW", SI_DERIVED, WATT, 1.0E3, true);
         MEGAWATT = new PowerUnit("PowerUnit.megawatt", "PowerUnit.MW", SI_DERIVED, WATT, 1.0E6, true);
         GIGAWATT = new PowerUnit("PowerUnit.gigawatt", "PowerUnit.GW", SI_DERIVED, WATT, 1.0E9, true);
         TERAWATT = new PowerUnit("PowerUnit.terawatt", "PowerUnit.TW", SI_DERIVED, WATT, 1.0E12, true);
         PETAWATT = new PowerUnit("PowerUnit.petawatt", "PowerUnit.PW", SI_DERIVED, WATT, 1.0E15, true);
         FOOT_POUND_FORCE_PER_HOUR = new PowerUnit(ForceUnit.POUND_FORCE, LengthUnit.FOOT, DurationUnit.HOUR,
                 "PowerUnit.foot_pound-force_per_hour", "PowerUnit.ft.lbf/h", IMPERIAL, true);
         FOOT_POUND_FORCE_PER_MINUTE = new PowerUnit(ForceUnit.POUND_FORCE, LengthUnit.FOOT, DurationUnit.MINUTE,
                 "PowerUnit.foot_pound-force_per_minute", "PowerUnit.ft.lbf/min", IMPERIAL, true);
         FOOT_POUND_FORCE_PER_SECOND = new PowerUnit(ForceUnit.POUND_FORCE, LengthUnit.FOOT, DurationUnit.SECOND,
                 "PowerUnit.foot_pound-force_per_second", "PowerUnit.ft.lbf/s", IMPERIAL, true);
         HORSEPOWER_METRIC = new PowerUnit("PowerUnit.horsepower_(metric)", "PowerUnit.hp", OTHER, WATT, 735.49875, true);
         STHENE_METER_PER_SECOND = new PowerUnit(ForceUnit.STHENE, LengthUnit.METER, DurationUnit.SECOND,
                 "PowerUnit.sthene-meter_per_second", "PowerUnit.sn.m/s", MTS, true);
         ERG_PER_SECOND = new PowerUnit(ForceUnit.DYNE, LengthUnit.CENTIMETER, DurationUnit.SECOND, "PowerUnit.erg_per_second",
                 "PowerUnit.erg/s", CGS, true);
     }
 
     /**
      * Define a PowerUnit based on its constituent base units, e.g. a W = km.m^2/s^3.
      * @param massUnit MassUnit; the unit of mass for the power unit, e.g., kilogram
      * @param lengthUnit LengthUnit; the unit of length for the power unit, e.g., meter
      * @param durationUnit DurationUnit; the unit of time for the power unit, e.g., second
      * @param nameOrNameKey String; if standardUnit: the key to the locale file for the long name of the unit, otherwise the
      *            name itself
      * @param abbreviationOrAbbreviationKey String; if standardUnit: the key to the locale file for the abbreviation of the
      *            unit, otherwise the abbreviation itself
      * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
      * @param standardUnit boolean; indicates whether it is a standard unit with a definition in the locale, or a user-defined
      *            unit
      */
     private PowerUnit(final MassUnit massUnit, final LengthUnit lengthUnit, final DurationUnit durationUnit,
             final String nameOrNameKey, final String abbreviationOrAbbreviationKey, final UnitSystem unitSystem,
             final boolean standardUnit)
     {
         super(nameOrNameKey, abbreviationOrAbbreviationKey, unitSystem, WATT, massUnit.getScaleFactor()
                 * lengthUnit.getScaleFactor() * lengthUnit.getScaleFactor() / Math.pow(durationUnit.getScaleFactor(), 3.0),
                 standardUnit);
         this.massUnit = massUnit;
         this.lengthUnit = lengthUnit;
         this.durationUnit = durationUnit;
     }
 
     /**
      * Define a user-defined PowerUnit based on its constituent base units, e.g. a W = km.m^2/s^3.
      * @param massUnit MassUnit; the unit of mass for the power unit, e.g., kilogram
      * @param lengthUnit LengthUnit; the unit of length for the power unit, e.g., meter
      * @param durationUnit DurationUnit; the unit of time for the power unit, e.g., second
      * @param name String; the long name of the unit
      * @param abbreviation String; the abbreviation of the unit otherwise the abbreviation itself
      * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
      */
     public PowerUnit(final MassUnit massUnit, final LengthUnit lengthUnit, final DurationUnit durationUnit, final String name,
             final String abbreviation, final UnitSystem unitSystem)
     {
         this(massUnit, lengthUnit, durationUnit, name, abbreviation, unitSystem, false);
     }
 
     /**
      * Define an PowerUnit based on a LengthUnit, a ForceUnit, and a TimeUnit, e.g. a W = N.m/s.
      * @param forceUnit ForceUnit; the unit of force for the power unit, e.g., Newton
      * @param lengthUnit LengthUnit; the unit of length for the power unit, e.g., meter
      * @param durationUnit DurationUnit; the unit of time for the power unit, e.g., second
      * @param nameOrNameKey String; if standardUnit: the key to the locale file for the long name of the unit, otherwise the
      *            name itself
      * @param abbreviationOrAbbreviationKey String; if standardUnit: the key to the locale file for the abbreviation of the
      *            unit, otherwise the abbreviation itself
      * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
      * @param standardUnit boolean; indicates whether it is a standard unit with a definition in the locale, or a user-defined
      *            unit
      */
     private PowerUnit(final ForceUnit forceUnit, final LengthUnit lengthUnit, final DurationUnit durationUnit,
             final String nameOrNameKey, final String abbreviationOrAbbreviationKey, final UnitSystem unitSystem,
             final boolean standardUnit)
     {
         super(nameOrNameKey, abbreviationOrAbbreviationKey, unitSystem, WATT,
                 lengthUnit.getScaleFactor() * forceUnit.getScaleFactor() / durationUnit.getScaleFactor(), standardUnit);
         this.massUnit = forceUnit.getMassUnit();
         this.lengthUnit = forceUnit.getLengthUnit();
         this.durationUnit = forceUnit.getDurationUnit();
     }
 
     /**
      * Define a user-defined PowerUnit based on a LengthUnit, a ForceUnit, and a TimeUnit, e.g. a W = N.m/s.
      * @param lengthUnit LengthUnit; the unit of length for the power unit, e.g., meter
      * @param forceUnit ForceUnit; the unit of force for the power unit, e.g., Newton
      * @param durationUnit DurationUnit; the unit of time for the power unit, e.g., second
      * @param name String; the long name of the unit
      * @param abbreviation String; the abbreviation of the unit otherwise the abbreviation itself
      * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
      */
     public PowerUnit(final LengthUnit lengthUnit, final ForceUnit forceUnit, final DurationUnit durationUnit, final String name,
             final String abbreviation, final UnitSystem unitSystem)
     {
         this(forceUnit, lengthUnit, durationUnit, name, abbreviation, unitSystem, false);
     }
 
     /**
      * Build a PowerUnit with a conversion factor to another PowerUnit.
      * @param nameOrNameKey String; if standardUnit: the key to the locale file for the long name of the unit, otherwise the
      *            name itself
      * @param abbreviationOrAbbreviationKey String; if standardUnit: the key to the locale file for the abbreviation of the
      *            unit, otherwise the abbreviation itself
      * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
      * @param referenceUnit PowerUnit; the unit to convert to
      * @param scaleFactorToReferenceUnit double; multiply a value in this unit by the factor to convert to the given reference
      *            unit
      * @param standardUnit boolean; indicates whether it is a standard unit with a definition in the locale, or a user-defined
      *            unit
      */
     private PowerUnit(final String nameOrNameKey, final String abbreviationOrAbbreviationKey, final UnitSystem unitSystem,
             final PowerUnit referenceUnit, final double scaleFactorToReferenceUnit, final boolean standardUnit)
     {
         super(nameOrNameKey, abbreviationOrAbbreviationKey, unitSystem, referenceUnit, scaleFactorToReferenceUnit,
                 standardUnit);
         this.massUnit = referenceUnit.getMassUnit();
         this.lengthUnit = referenceUnit.getLengthUnit();
         this.durationUnit = referenceUnit.getDurationUnit();
     }
 
     /**
      * Build a user-defined PowerUnit with a conversion factor to another PowerUnit.
      * @param name String; the long name of the unit
      * @param abbreviation String; the abbreviation of the unit
      * @param unitSystem UnitSystem; the unit system, e.g. SI or Imperial
      * @param referenceUnit PowerUnit; the unit to convert to
      * @param scaleFactorToReferenceUnit double; multiply a value in this unit by the factor to convert to the given reference
      *            unit
      */
     public PowerUnit(final String name, final String abbreviation, final UnitSystem unitSystem, final PowerUnit referenceUnit,
             final double scaleFactorToReferenceUnit)
     {
         this(name, abbreviation, unitSystem, referenceUnit, scaleFactorToReferenceUnit, false);
     }
 
     /**
      * @return massUnit
      */
     public final MassUnit getMassUnit()
     {
         return this.massUnit;
     }
 
     /**
      * @return lengthUnit
      */
     public final LengthUnit getLengthUnit()
     {
         return this.lengthUnit;
     }
 
     /**
      * @return durationUnit
      */
     public final DurationUnit getDurationUnit()
     {
         return this.durationUnit;
     }
 
     /** {@inheritDoc} */
     @Override
     public final PowerUnit getStandardUnit()
     {
         return WATT;
     }
 
     /** {@inheritDoc} */
     @Override
     public final String getSICoefficientsString()
     {
         return "kgm2/s3";
     }
 
 }