package org.djunits.unit;
   
   import static org.djunits.unit.unitsystem.UnitSystem.CGS_EMU;
   import static org.djunits.unit.unitsystem.UnitSystem.CGS_ESU;
   import static org.djunits.unit.unitsystem.UnitSystem.SI_DERIVED;
   
   import org.djunits.unit.unitsystem.UnitSystem;
   
   /**
   * The units of electrical resistance.
   * <p>
   * Copyright (c) 2015-2018 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: 2018-01-28 03:17:44 +0100 (Sun, 28 Jan 2018) $, @version $Revision: 256 $, by $Author: averbraeck $,
   * initial version May 15, 2014 <br>
   * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
   */
  public class ElectricalResistanceUnit extends LinearUnit<ElectricalResistanceUnit>
  {
      /** */
      private static final long serialVersionUID = 20140607L;
  
      /** the unit of mass for the electrical resistance unit, e.g., kilogram. */
      private final MassUnit massUnit;
  
      /** the unit of length for the electrical resistance unit, e.g., meters. */
      private final LengthUnit lengthUnit;
  
      /** the unit of electrical current for the electrical resistance unit, e.g., Ampere. */
      private final ElectricalCurrentUnit electricalCurrentUnit;
  
      /** the unit of time for the electrical resistance unit, e.g., second. */
      private final DurationUnit durationUnit;
  
      /** The SI unit for electrical resistance is Ohm. */
      public static final ElectricalResistanceUnit SI;
  
      /** Ohm. */
      public static final ElectricalResistanceUnit OHM;
  
      /** nano-ohm. */
      public static final ElectricalResistanceUnit NANOOHM;
  
      /** micro-ohm. */
      public static final ElectricalResistanceUnit MICROOHM;
  
      /** milli-ohm. */
      public static final ElectricalResistanceUnit MILLIOHM;
  
      /** kilo-ohm. */
      public static final ElectricalResistanceUnit KILOOHM;
  
      /** mega-ohm. */
      public static final ElectricalResistanceUnit MEGAOHM;
  
      /** giga-ohm. */
      public static final ElectricalResistanceUnit GIGAOHM;
  
      /** ab-ohm. */
      public static final ElectricalResistanceUnit ABOHM;
  
      /** stat-ohm. */
      public static final ElectricalResistanceUnit STATOHM;
  
      static
      {
          SI = new ElectricalResistanceUnit(MassUnit.KILOGRAM, LengthUnit.METER, ElectricalCurrentUnit.AMPERE,
                  DurationUnit.SECOND, "ElectricalResistanceUnit.ohm_(name)", "ElectricalResistanceUnit.ohm", SI_DERIVED, true);
          OHM = SI;
          NANOOHM = new ElectricalResistanceUnit("ElectricalResistanceUnit.nano_ohm", "ElectricalResistanceUnit.n_ohm",
                  SI_DERIVED, OHM, 1.0E-9, true);
          MICROOHM = new ElectricalResistanceUnit("ElectricalResistanceUnit.micro_ohm", "ElectricalResistanceUnit.mu_ohm",
                  SI_DERIVED, OHM, 1.0E-6, true);
          MILLIOHM = new ElectricalResistanceUnit("ElectricalResistanceUnit.milli_ohm", "ElectricalResistanceUnit.m_ohm",
                  SI_DERIVED, OHM, 1.0E-3, true);
          KILOOHM = new ElectricalResistanceUnit("ElectricalResistanceUnit.kilo_ohm", "ElectricalResistanceUnit.k_ohm",
                  SI_DERIVED, OHM, 1.0E3, true);
          MEGAOHM = new ElectricalResistanceUnit("ElectricalResistanceUnit.mega_ohm", "ElectricalResistanceUnit.M_ohm",
                  SI_DERIVED, OHM, 1.0E06, true);
          GIGAOHM = new ElectricalResistanceUnit("ElectricalResistanceUnit.giga_ohm", "ElectricalResistanceUnit.G_ohm",
                  SI_DERIVED, OHM, 1.0E9, true);
          ABOHM = new ElectricalResistanceUnit("ElectricalResistanceUnit.ab_ohm", "ElectricalResistanceUnit.a_ohm", CGS_EMU, OHM,
                  1.0E-9, true);
          STATOHM = new ElectricalResistanceUnit("ElectricalResistanceUnit.stat_ohm", "ElectricalResistanceUnit.st_ohm", CGS_ESU,
                  OHM, 8.987551787E11, true);
      }
  
      /**
       * Define an ElectricalResistanceUnit based on its constituent base units, e.g. an Ohm = km.m^2/A^2.s^3.
       * @param massUnit the unit of mass for the electrical resistance unit, e.g., kilogram
       * @param lengthUnit the unit of length for the electrical resistance unit, e.g., meter
       * @param electricalCurrentUnit the unit of electrical current for the electrical resistance unit, e.g., Ampere
       * @param durationUnit the unit of time for the electrical resistance unit, e.g., second
       * @param nameOrNameKey if standardUnit: the key to the locale file for the long name of the unit, otherwise the name itself
       * @param abbreviationOrAbbreviationKey if standardUnit: the key to the locale file for the abbreviation of the unit,
       *            otherwise the abbreviation itself
       * @param unitSystem the unit system, e.g. SI or Imperial
       * @param standardUnit indicates whether it is a standard unit with a definition in the locale, or a user-defined unit
      */
     @SuppressWarnings("checkstyle:parameternumber")
     private ElectricalResistanceUnit(final MassUnit massUnit, final LengthUnit lengthUnit,
             final ElectricalCurrentUnit electricalCurrentUnit, final DurationUnit durationUnit, final String nameOrNameKey,
             final String abbreviationOrAbbreviationKey, final UnitSystem unitSystem, final boolean standardUnit)
     {
         super(nameOrNameKey, abbreviationOrAbbreviationKey, unitSystem, OHM,
                 massUnit.getScaleFactor() * lengthUnit.getScaleFactor()
                         * lengthUnit.getScaleFactor() / (electricalCurrentUnit.getScaleFactor()
                                 * electricalCurrentUnit.getScaleFactor() * Math.pow(durationUnit.getScaleFactor(), 3.0)),
                 standardUnit);
         this.massUnit = massUnit;
         this.lengthUnit = lengthUnit;
         this.electricalCurrentUnit = electricalCurrentUnit;
         this.durationUnit = durationUnit;
     }
 
     /**
      * Define a user-defined ElectricalResistanceUnit based on its constituent base units, e.g. an Ohm = km.m^2/A^2.s^3.
      * @param massUnit the unit of mass for the electrical resistance unit, e.g., kilogram
      * @param lengthUnit the unit of length for the electrical resistance unit, e.g., meter
      * @param electricalCurrentUnit the unit of electrical current for the electrical resistance unit, e.g., Ampere
      * @param durationUnit the unit of time for the electrical resistance unit, e.g., second
      * @param name the long name of the unit
      * @param abbreviation the abbreviation of the unit
      * @param unitSystem the unit system, e.g. SI or Imperial
      */
     public ElectricalResistanceUnit(final MassUnit massUnit, final LengthUnit lengthUnit,
             final ElectricalCurrentUnit electricalCurrentUnit, final DurationUnit durationUnit, final String name,
             final String abbreviation, final UnitSystem unitSystem)
     {
         this(massUnit, lengthUnit, electricalCurrentUnit, durationUnit, name, abbreviation, unitSystem, false);
     }
 
     /**
      * Define an ElectricalResistanceUnit based on an electrical potential unit and an electrical current unit, e.g. Ohm = V/A.
      * @param electricalPotentialUnit the unit of electrical potential difference for the electrical resistance unit, e.g., Volt
      * @param electricalCurrentUnit the unit of electrical current for the electrical resistance unit, e.g., Ampere
      * @param nameOrNameKey if standardUnit: the key to the locale file for the long name of the unit, otherwise the name itself
      * @param abbreviationOrAbbreviationKey if standardUnit: the key to the locale file for the abbreviation of the unit,
      *            otherwise the abbreviation itself
      * @param unitSystem the unit system, e.g. SI or Imperial
      * @param standardUnit indicates whether it is a standard unit with a definition in the locale, or a user-defined unit
      */
     private ElectricalResistanceUnit(final ElectricalPotentialUnit electricalPotentialUnit,
             final ElectricalCurrentUnit electricalCurrentUnit, final String nameOrNameKey,
             final String abbreviationOrAbbreviationKey, final UnitSystem unitSystem, final boolean standardUnit)
     {
         super(nameOrNameKey, abbreviationOrAbbreviationKey, unitSystem, OHM,
                 electricalPotentialUnit.getScaleFactor() / electricalCurrentUnit.getScaleFactor(), standardUnit);
         this.massUnit = electricalPotentialUnit.getMassUnit();
         this.lengthUnit = electricalPotentialUnit.getLengthUnit();
         this.electricalCurrentUnit = electricalCurrentUnit;
         this.durationUnit = electricalPotentialUnit.getDurationUnit();
     }
 
     /**
      * Define a user-defined ElectricalResistanceUnit based on an electrical potential unit and an electrical current unit, e.g.
      * Ohm = V/A.
      * @param electricalPotentialUnit the unit of electrical potential difference for the electrical resistance unit, e.g., Volt
      * @param electricalCurrentUnit the unit of electrical current for the electrical resistance unit, e.g., Ampere
      * @param name the long name of the unit
      * @param abbreviation the abbreviation of the unit
      * @param unitSystem the unit system, e.g. SI or Imperial
      */
     public ElectricalResistanceUnit(final ElectricalPotentialUnit electricalPotentialUnit,
             final ElectricalCurrentUnit electricalCurrentUnit, final String name, final String abbreviation,
             final UnitSystem unitSystem)
     {
         this(electricalPotentialUnit, electricalCurrentUnit, name, abbreviation, unitSystem, false);
     }
 
     /**
      * Build a ElectricalResistanceUnit with a conversion factor to another ElectricalResistanceUnit.
      * @param nameOrNameKey if standardUnit: the key to the locale file for the long name of the unit, otherwise the name itself
      * @param abbreviationOrAbbreviationKey if standardUnit: the key to the locale file for the abbreviation of the unit,
      *            otherwise the abbreviation itself
      * @param unitSystem the unit system, e.g. SI or Imperial
      * @param referenceUnit the unit to convert to
      * @param scaleFactorToReferenceUnit multiply a value in this unit by the factor to convert to the given reference unit
      * @param standardUnit indicates whether it is a standard unit with a definition in the locale, or a user-defined unit
      */
     private ElectricalResistanceUnit(final String nameOrNameKey, final String abbreviationOrAbbreviationKey,
             final UnitSystem unitSystem, final ElectricalResistanceUnit referenceUnit, final double scaleFactorToReferenceUnit,
             final boolean standardUnit)
     {
         super(nameOrNameKey, abbreviationOrAbbreviationKey, unitSystem, referenceUnit, scaleFactorToReferenceUnit,
                 standardUnit);
         this.massUnit = referenceUnit.getMassUnit();
         this.lengthUnit = referenceUnit.getLengthUnit();
         this.electricalCurrentUnit = referenceUnit.getElectricalCurrentUnit();
         this.durationUnit = referenceUnit.getDurationUnit();
     }
 
     /**
      * Build a user-defined ElectricalResistanceUnit with a conversion factor to another ElectricalResistanceUnit.
      * @param name the long name of the unit
      * @param abbreviation the abbreviation of the unit
      * @param unitSystem the unit system, e.g. SI or Imperial
      * @param referenceUnit the unit to convert to
      * @param scaleFactorToReferenceUnit multiply a value in this unit by the factor to convert to the given reference unit
      */
     public ElectricalResistanceUnit(final String name, final String abbreviation, final UnitSystem unitSystem,
             final ElectricalResistanceUnit 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 electricalCurrentUnit
      */
     public final ElectricalCurrentUnit getElectricalCurrentUnit()
     {
         return this.electricalCurrentUnit;
     }
 
     /**
      * @return durationUnit
      */
     public final DurationUnit getDurationUnit()
     {
         return this.durationUnit;
     }
 
     /** {@inheritDoc} */
     @Override
     public final ElectricalResistanceUnit getStandardUnit()
     {
         return OHM;
     }
 
     /** {@inheritDoc} */
     @Override
     public final String getSICoefficientsString()
     {
         return "kgm2/s3A2";
     }
 
 }