Package tech.units.indriya

Class AbstractUnit<Q extends javax.measure.Quantity<Q>>

java.lang.Object
tech.units.indriya.AbstractUnit<Q>
All Implemented Interfaces:
Serializable, Comparable<javax.measure.Unit<Q>>, javax.measure.Unit<Q>, ComparableUnit<Q>
Direct Known Subclasses:
AlternateUnit, AnnotatedUnit, BaseUnit, ProductUnit, TransformedUnit
public abstract class AbstractUnit<Q extends javax.measure.Quantity<Q>> extends Object implements ComparableUnit<Q>

The class represents units founded on the seven SI base units for seven base quantities assumed to be mutually independent.

For all physics units, unit conversions are symmetrical: u1.getConverterTo(u2).equals(u2.getConverterTo(u1).inverse()). Non-physical units (e.g. currency units) for which conversion is not symmetrical should have their own separate class hierarchy and are considered distinct (e.g. financial units), although they can always be combined with physics units (e.g. "€/Kg", "$/h").

Since:
1.0
Version:
1.2, April 11, 2018
See Also:

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    protected static final class 
    AbstractUnit.Equalizer
    Utility class for number comparison and equality

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected String
    name
    Holds the name.
    static final javax.measure.Unit<javax.measure.quantity.Dimensionless>
    ONE
    Holds the dimensionless unit ONE.
    private static final long
    serialVersionUID
     
    private String
    symbol
    Holds the symbol.
    protected static final Map<String,javax.measure.Unit<?>>
    SYMBOL_TO_UNIT
    Holds the unique symbols collection (base units or alternate units).

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    AbstractUnit()
    Default constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    final javax.measure.Unit<Q>
    alternate(String symbol)
     
    javax.measure.Unit<Q>
    annotate(String annotation)
    Annotates the specified unit.
    final <T extends javax.measure.Quantity<T>>
    AbstractUnit<T>
    asType(Class<T> type)
    Casts this unit to a parameterized unit of specified nature or throw a ClassCastException if the dimension of the specified quantity and this unit's dimension do not match (regardless whether or not the dimensions are independent or not).
    int
    compareTo(javax.measure.Unit<Q> that)
    Compares this unit to the specified unit.
    (package private) static javax.measure.UnitConverter
    converterOf(double factor)
     
    final javax.measure.Unit<Q>
    divide(double divisor)
    Returns the result of dividing this unit by the specified divisor.
    final javax.measure.Unit<?>
    divide(javax.measure.Unit<?> that)
    Returns the quotient of this unit with the one specified.
    protected final javax.measure.Unit<?>
    divide(AbstractUnit<?> that)
    Returns the quotient of this physical unit with the one specified.
    abstract boolean
    equals(Object obj)
     
    protected Type
    getActualType()
     
    abstract Map<? extends javax.measure.Unit<?>,Integer>
    getBaseUnits()
     
    final javax.measure.UnitConverter
    getConverterTo(javax.measure.Unit<Q> that)
     
    final javax.measure.UnitConverter
    getConverterToAny(javax.measure.Unit<?> that)
     
    abstract javax.measure.Dimension
    getDimension()
     
    String
    getName()
     
    String
    getSymbol()
     
    abstract javax.measure.UnitConverter
    getSystemConverter()
    Returns the converter from this unit to its unscaled
    invalid reference 
    System Unit
    unit.
    final javax.measure.Unit<Q>
    getSystemUnit()
    Returns the system unit (unscaled SI unit) from which this unit is derived.
    abstract int
    hashCode()
     
    private final javax.measure.UnitConverter
    internalGetConverterTo(javax.measure.Unit<Q> that, boolean useEquals)
     
    private final boolean
    internalIsCompatible(javax.measure.Unit<?> that, boolean checkEquals)
    Internal helper for isCompatible
    final javax.measure.Unit<?>
    inverse()
    Returns the inverse of this physical unit.
    final boolean
    isCompatible(javax.measure.Unit<?> that)
    Indicates if this unit is compatible with the unit specified.
    boolean
    isEquivalentOf(javax.measure.Unit<Q> that)
    Compares two instances of , doing the conversion of unit if necessary.
    private static boolean
    isLongValue(double value)
     
    boolean
    isSystemUnit()
    Indicates if this unit belongs to the set of coherent SI units (unscaled SI units).
    final javax.measure.Unit<Q>
    multiply(double factor)
     
    final javax.measure.Unit<?>
    multiply(javax.measure.Unit<?> that)
    Returns the product of this unit with the one specified.
    protected final javax.measure.Unit<?>
    multiply(AbstractUnit<?> that)
    Returns the product of this physical unit with the one specified.
    static javax.measure.Unit<?>
    parse(CharSequence charSequence)
    Returns the abstract unit represented by the specified characters as per default format.
    final javax.measure.Unit<?>
    pow(int n)
    Returns a unit equals to this unit raised to an exponent.
    AbstractUnit<Q>
    prefix(Prefix prefix)
     
    final javax.measure.Unit<?>
    root(int n)
    Returns a unit equals to the given root of this unit.
    protected void
    setName(String name)
     
    protected void
    setSymbol(String s)
     
    final javax.measure.Unit<Q>
    shift(double offset)
     
    String
    toString()
    Returns the standard representation of this physics unit.
    protected abstract javax.measure.Unit<Q>
    toSystemUnit()
    Returns the unscaled
    invalid reference 
    SI
    unit from which this unit is derived.
    final javax.measure.Unit<Q>
    transform(javax.measure.UnitConverter operation)
     

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

  • Field Details

  • Constructor Details

    • AbstractUnit

      protected AbstractUnit()
      Default constructor.

  • Method Details

    • getActualType

      protected Type getActualType()

    • isSystemUnit

      public boolean isSystemUnit()
      Indicates if this unit belongs to the set of coherent SI units (unscaled SI units). The base and coherent derived units of the SI form a coherent set, designated the set of coherent SI units. The word coherent is used here in the following sense: when coherent units are used, equations between the numerical values of quantities take exactly the same form as the equations between the quantities themselves. Thus if only units from a coherent set are used, conversion factors between units are never required.
      Specified by:
      isSystemUnit in interface ComparableUnit<Q extends javax.measure.Quantity<Q>>
      Returns:
      equals(toSystemUnit())

    • toSystemUnit

      protected abstract javax.measure.Unit<Q> toSystemUnit()
      Returns the unscaled
      invalid reference 
      SI
      unit from which this unit is derived. The SI unit can be be used to identify a quantity given the unit. For example: static boolean isAngularVelocity(AbstractUnitinvalid input: '<'?> unit) { return unit.toSystemUnit().equals(RADIAN.divide(SECOND)); } assert(REVOLUTION.divide(MINUTE).isAngularVelocity()); // Returns true.
      Returns:
      the unscaled metric unit from which this unit is derived.

    • getSystemConverter

      public abstract javax.measure.UnitConverter getSystemConverter()
      Returns the converter from this unit to its unscaled
      invalid reference 
      System Unit
      unit.
      Returns:
      getConverterTo(this.toSystemUnit())
      See Also:

    • annotate

      public javax.measure.Unit<Q> annotate(String annotation)
      Annotates the specified unit. Annotation does not change the unit semantic. Annotations are often written between curly braces behind units. For example:
      Unit PERCENT_VOL = ((AbstractUnit)Units.PERCENT).annotate("vol"); // "%{vol}" Unit KG_TOTAL = ((AbstractUnit)Units.KILOGRAM).annotate("total"); // "kg{total}" Unit RED_BLOOD_CELLS = ((AbstractUnit)Units.ONE).annotate("RBC"); // "{RBC}" Note: Annotation of system units are not considered themselves as system units.
      Parameters:
      annotation - the unit annotation.
      Returns:
      the annotated unit.

    • parse

      public static javax.measure.Unit<?> parse(CharSequence charSequence)
      Returns the abstract unit represented by the specified characters as per default format. Locale-sensitive unit parsing could be handled using LocalUnitFormat in subclasses of AbstractUnit.

      Note: The standard format supports dimensionless units. AbstractUnit PERCENT = AbstractUnit.parse("100").inverse().asType(Dimensionless.class);

      Parameters:
      charSequence - the character sequence to parse.
      Returns:
      SimpleUnitFormat.getInstance().parse(csq, new ParsePosition(0))
      Throws:
      javax.measure.format.ParserException - if the specified character sequence cannot be correctly parsed (e.g. not UCUM compliant).

    • toString

      public String toString()
      Returns the standard representation of this physics unit. The string produced for a given unit is always the same; it is not affected by the locale. It can be used as a canonical string representation for exchanging units, or as a key for a Hashtable, etc. Locale-sensitive unit parsing could be handled using LocalUnitFormat in subclasses of AbstractUnit.
      Specified by:
      toString in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Overrides:
      toString in class Object
      Returns:
      SimpleUnitFormat.getInstance().format(this)

    • getSystemUnit

      public final javax.measure.Unit<Q> getSystemUnit()
      Returns the system unit (unscaled SI unit) from which this unit is derived. They can be be used to identify a quantity given the unit. For example:
      static boolean isAngularVelocity(AbstractUnitinvalid input: '<'?> unit) {
        return unit.getSystemUnit().equals(RADIAN.divide(SECOND));
      }
      assert(REVOLUTION.divide(MINUTE).isAngularVelocity()); // Returns true.
      Specified by:
      getSystemUnit in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Returns:
      the unscaled metric unit from which this unit is derived.

    • isCompatible

      public final boolean isCompatible(javax.measure.Unit<?> that)
      Indicates if this unit is compatible with the unit specified. To be compatible both units must be physics units having the same fundamental dimension.
      Specified by:
      isCompatible in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - the other unit.
      Returns:
      true if this unit and that unit have equals fundamental dimension according to the current physics model; false otherwise.

    • asType

      public final <T extends javax.measure.Quantity<T>> AbstractUnit<T> asType(Class<T> type)
      Casts this unit to a parameterized unit of specified nature or throw a ClassCastException if the dimension of the specified quantity and this unit's dimension do not match (regardless whether or not the dimensions are independent or not).
      Specified by:
      asType in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Parameters:
      type - the quantity class identifying the nature of the unit.
      Throws:
      ClassCastException - if the dimension of this unit is different from the SI dimension of the specified type.
      See Also:

    • getBaseUnits

      public abstract Map<? extends javax.measure.Unit<?>,Integer> getBaseUnits()
      Specified by:
      getBaseUnits in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>

    • getDimension

      public abstract javax.measure.Dimension getDimension()
      Specified by:
      getDimension in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>

    • setName

      protected void setName(String name)

    • getName

      public String getName()
      Specified by:
      getName in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>

    • getSymbol

      public String getSymbol()
      Specified by:
      getSymbol in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>

    • setSymbol

      protected void setSymbol(String s)

    • getConverterTo

      public final javax.measure.UnitConverter getConverterTo(javax.measure.Unit<Q> that) throws javax.measure.UnconvertibleException
      Specified by:
      getConverterTo in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Throws:
      javax.measure.UnconvertibleException

    • getConverterToAny

      public final javax.measure.UnitConverter getConverterToAny(javax.measure.Unit<?> that) throws javax.measure.IncommensurableException, javax.measure.UnconvertibleException
      Specified by:
      getConverterToAny in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Throws:
      javax.measure.IncommensurableException
      javax.measure.UnconvertibleException

    • alternate

      public final javax.measure.Unit<Q> alternate(String symbol)
      Specified by:
      alternate in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>

    • transform

      public final javax.measure.Unit<Q> transform(javax.measure.UnitConverter operation)
      Specified by:
      transform in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>

    • shift

      public final javax.measure.Unit<Q> shift(double offset)
      Specified by:
      shift in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>

    • multiply

      public final javax.measure.Unit<Q> multiply(double factor)
      Specified by:
      multiply in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>

    • internalIsCompatible

      private final boolean internalIsCompatible(javax.measure.Unit<?> that, boolean checkEquals)
      Internal helper for isCompatible

    • internalGetConverterTo

      private final javax.measure.UnitConverter internalGetConverterTo(javax.measure.Unit<Q> that, boolean useEquals) throws javax.measure.UnconvertibleException
      Throws:
      javax.measure.UnconvertibleException

    • isLongValue

      private static boolean isLongValue(double value)

    • converterOf

      static javax.measure.UnitConverter converterOf(double factor)

    • multiply

      public final javax.measure.Unit<?> multiply(javax.measure.Unit<?> that)
      Returns the product of this unit with the one specified.

      Note: If the specified unit (that) is not a physical unit, then that.multiply(this) is returned.

      Specified by:
      multiply in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - the unit multiplicand.
      Returns:
      this * that

    • multiply

      protected final javax.measure.Unit<?> multiply(AbstractUnit<?> that)
      Returns the product of this physical unit with the one specified.
      Parameters:
      that - the physical unit multiplicand.
      Returns:
      this * that

    • inverse

      public final javax.measure.Unit<?> inverse()
      Returns the inverse of this physical unit.
      Specified by:
      inverse in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Returns:
      1 / this

    • divide

      public final javax.measure.Unit<Q> divide(double divisor)
      Returns the result of dividing this unit by the specified divisor. If the factor is an integer value, the division is exact. For example: 
       
    QUART = GALLON_LIQUID_US.divide(4); // Exact definition.
      Specified by:
      divide in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Parameters:
      divisor - the divisor value.
      Returns:
      this unit divided by the specified divisor.

    • divide

      public final javax.measure.Unit<?> divide(javax.measure.Unit<?> that)
      Returns the quotient of this unit with the one specified.
      Specified by:
      divide in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - the unit divisor.
      Returns:
      this.multiply(that.inverse())

    • divide

      protected final javax.measure.Unit<?> divide(AbstractUnit<?> that)
      Returns the quotient of this physical unit with the one specified.
      Parameters:
      that - the physical unit divisor.
      Returns:
      this.multiply(that.inverse())

    • root

      public final javax.measure.Unit<?> root(int n)
      Returns a unit equals to the given root of this unit.
      Specified by:
      root in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Parameters:
      n - the root's order.
      Returns:
      the result of taking the given root of this unit.
      Throws:
      ArithmeticException - if n == 0 or if this operation would result in an unit with a fractional exponent.

    • pow

      public final javax.measure.Unit<?> pow(int n)
      Returns a unit equals to this unit raised to an exponent.
      Specified by:
      pow in interface javax.measure.Unit<Q extends javax.measure.Quantity<Q>>
      Parameters:
      n - the exponent.
      Returns:
      the result of raising this unit to the exponent.

    • prefix

      public AbstractUnit<Q> prefix(Prefix prefix)

    • compareTo

      public int compareTo(javax.measure.Unit<Q> that)
      Compares this unit to the specified unit. The default implementation compares the name and symbol of both this unit and the specified unit.
      Specified by:
      compareTo in interface Comparable<Q extends javax.measure.Quantity<Q>>
      Returns:
      a negative integer, zero, or a positive integer as this unit is less than, equal to, or greater than the specified unit.

    • isEquivalentOf

      public boolean isEquivalentOf(javax.measure.Unit<Q> that)
      Description copied from interface: ComparableUnit
      Compares two instances of , doing the conversion of unit if necessary.
      Specified by:
      isEquivalentOf in interface ComparableUnit<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - the Unit<Q> to be compared with this instance.
      Returns:
      true if that < this.

    • equals

      public abstract boolean equals(Object obj)
      Overrides:
      equals in class Object

    • hashCode

      public abstract int hashCode()
      Overrides:
      hashCode in class Object