Unit (DJUNITS 3.01.03 API)

java.lang.Object
- org.djunits.unit.Unit<U>

Type Parameters:

U - the unit for transformation reasons

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

AngleUnit, DimensionlessUnit, LinearUnit, SIUnit
```
public abstract class Unit<U extends Unit<U>>
extends Object
implements Serializable
```
All units are internally stored relative to a standard unit with conversion factor. This means that e.g., a meter is stored with conversion factor 1.0, whereas kilometer is stored with a conversion factor 1000.0. This means that if we want to express a length meter in kilometers, we have to divide by the conversion factor.
Copyright (c) 2015-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
BSD-style license. See DJUNITS License.
$LastChangedDate: 2019-03-03 00:53:50 +0100 (Sun, 03 Mar 2019) $, @version $Revision: 349 $, by $Author: averbraeck $, initial version May 15, 2014

Author:

Alexander Verbraeck

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type Field and Description

static String[] STANDARD_UNITS
The array of the names of the standard units.

Fields
Modifier and Type	Field and Description
`static String[]`	`STANDARD_UNITS` The array of the names of the standard units.

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`Unit(String name, String abbreviation, UnitSystem unitSystem)` Build a user-defined unit and create the fields for that unit.
`protected`	`Unit(String name, String abbreviation, UnitSystem unitSystem, Scale scale)` Build a user-defined unit with a specific conversion scale to/from the standard unit.
`protected`	`Unit(String abbreviationKey, UnitSystem unitSystem)` Build a standard unit and create the fields for that unit.
`protected`	`Unit(String abbreviationKey, UnitSystem unitSystem, Scale scale)` Build a standard unit with a specific conversion scale to/from the standard unit.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`equals(Object obj)`
`abstract boolean`	`equalsIgnoreNaming(Object obj)` Test if two units are the same, except for the name and abbreviation.
`int`	`generateHashCode()` Generate a hashCode for caching.
`String`	`getAbbreviation()`
`String`	`getAbbreviationKey()` This method returns the abbreviation key, or null in case the abbreviation is hard coded.
`Set<Unit<U>>`	`getAllUnitsOfThisType()` Return a copy of the set of all defined units for this unit type.
`String`	`getDefaultLocaleAbbreviation()`
`String`	`getDefaultLocaleName()`
`String`	`getDefaultLocaleTextualRepresentation()`
`List<String>`	`getDefaultLocaleTextualRepresentations()`
`String`	`getDefaultTextualRepresentation()`
`String`	`getName()`
`Scale`	`getScale()`
`SICoefficients`	`getSICoefficients()`
`abstract String`	`getSICoefficientsString()`
`abstract U`	`getStandardUnit()`
`List<String>`	`getTextualRepresentations()`
`static <V extends Unit<V>> Set<V>`	`getUnits(Class<V> unitClass)` Return a set of defined units for a given unit type.
`UnitSystem`	`getUnitSystem()`
`int`	`hashCode()`
`boolean`	`isBaseSIUnit()` Determine whether this unit is the standard unit.
`boolean`	`isLocalizable()` Report if this unit support localization.
`static SIUnit`	`lookupOrCreateSIUnitWithSICoefficients(String normalizedSICoefficientsString)`
`static Set<Unit<?>>`	`lookupOrCreateUnitWithSICoefficients(String normalizedSICoefficientsString)`
`static Set<Unit<?>>`	`lookupUnitWithSICoefficients(String normalizedSICoefficientsString)`
`String`	`toString()`

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - STANDARD_UNITS
```
public static final String[] STANDARD_UNITS
```
    The array of the names of the standard units.
- Constructor Detail
  - Unit
```
protected Unit(String abbreviationKey,
               UnitSystem unitSystem)
```
    Build a standard unit and create the fields for that unit. For a standard unit, a UnitException is silently ignored.
    
    Parameters:
    
    abbreviationKey - String; the key to the locale file for the abbreviation of the unit
    
    unitSystem - UnitSystem; the unit system, e.g. SI or Imperial
  - Unit
```
protected Unit(String abbreviationKey,
               UnitSystem unitSystem,
               Scale scale)
```
    Build a standard unit with a specific conversion scale to/from the standard unit. For a standard unit, a UnitException is silently ignored.
    
    Parameters:
    
    abbreviationKey - String; the key to the locale file for the abbreviation of the unit, otherwise the abbreviation itself
    
    unitSystem - UnitSystem; the unit system, e.g. SI or Imperial
    
    scale - Scale; the conversion scale to use for this unit
  - Unit
```
protected Unit(String name,
               String abbreviation,
               UnitSystem unitSystem)
```
    Build a user-defined unit and create the fields for that unit. This unit is a user-defined unit where the localization files do not have an entry. A UnitException is thrown as a RunTimeException.
    
    Parameters:
    
    name - String; the key to the locale file for the long name of the unit, otherwise the name itself
    
    abbreviation - String; the key to the locale file for the abbreviation of the unit, otherwise the abbreviation itself
    
    unitSystem - UnitSystem; the unit system, e.g. SI or Imperial
  - Unit
```
protected Unit(String name,
               String abbreviation,
               UnitSystem unitSystem,
               Scale scale)
```
    Build a user-defined unit with a specific conversion scale to/from the standard unit. This unit is a user-defined unit where the localization files do not have an entry. A UnitException is thrown as a RunTimeException.
    
    Parameters:
    
    name - String; the key to the locale file for the long name of the unit, otherwise the name itself
    
    abbreviation - String; the key to the locale file for the abbreviation of the unit, otherwise the abbreviation itself
    
    unitSystem - UnitSystem; the unit system, e.g. SI or Imperial
    
    scale - Scale; the conversion scale to use for this unit
- Method Detail
  - isLocalizable
```
public final boolean isLocalizable()
```
    Report if this unit support localization.
    
    Returns:
    
    boolean; true if this unit supports localization; false if it does not
  - getUnits
```
public static <V extends Unit<V>> Set<V> getUnits(Class<V> unitClass)
```
    Return a set of defined units for a given unit type.
    
    Type Parameters:
    
    V - the unit type to use in this method.
    
    Parameters:
    
    unitClass - Class<V>; the class for which the units are requested, e.g. ForceUnit.class
    
    Returns:
    
    the set of defined units belonging to the provided class. The empty set will be returned in case the unit type does not have any units.
  - getAllUnitsOfThisType
```
public final Set<Unit<U>> getAllUnitsOfThisType()
```
    Return a copy of the set of all defined units for this unit type.
    
    Returns:
    
    the set of defined units belonging to this Unit class. The empty set will be returned in case the unit type does not have any units.
  - getName
```
public final String getName()
```
    Returns:
    
    name, e.g. meters per second
  - getDefaultLocaleName
```
public final String getDefaultLocaleName()
```
    Returns:
    
    the name in the default locale, e.g. meters per second
  - getAbbreviation
```
public final String getAbbreviation()
```
    Returns:
    
    abbreviation, e.g., m/s
  - getDefaultLocaleAbbreviation
```
public final String getDefaultLocaleAbbreviation()
```
    Returns:
    
    the abbreviation in the default locale, e.g., m/s
  - getAbbreviationKey
```
public final String getAbbreviationKey()
```
    This method returns the abbreviation key, or null in case the abbreviation is hard coded.
    
    Returns:
    
    abbreviation key, e.g. DurationUnit.m/s, or null for a user-defined unit
  - getTextualRepresentations
```
public final List<String> getTextualRepresentations()
```
    Returns:
    
    the textual display types of the unit. In case the list contains more than one abbreviation, the first one is the default one. In case none is available, the standard abbreviation is used. In case that one is also not available the abbreviation key is used.
  - getDefaultLocaleTextualRepresentations
```
public final List<String> getDefaultLocaleTextualRepresentations()
```
    Returns:
    
    the textual display types of the unit in the default locale; In case the list contains more than one abbreviation, the first one is the default one. In case none is available, the standard abbreviation is used. In case that one is also not available the abbreviation key is used.
  - getDefaultTextualRepresentation
```
public final String getDefaultTextualRepresentation()
```
    Returns:
    
    the default textual display representation of the unit; In case there are more textual representations, the first one is the default one. In case none is available, the standard abbreviation is used. In case that one is also not available the abbreviation key is used.
  - getDefaultLocaleTextualRepresentation
```
public final String getDefaultLocaleTextualRepresentation()
```
    Returns:
    
    the default textual display representation of the unit in the default locale; In case there are more textual representations, the first one is the default one. In case none is available, the standard abbreviation is used. In case that one is also not available the abbreviation key is used.
  - getScale
```
public Scale getScale()
```
    Returns:
    
    the scale to transform between this unit and the reference (e.g., SI) unit.
  - getUnitSystem
```
public final UnitSystem getUnitSystem()
```
    Returns:
    
    unitSystem, e.g. SI or Imperial
  - getStandardUnit
```
public abstract U getStandardUnit()
```
    Returns:
    
    the SI standard unit for this unit, or the de facto standard unit if SI is not available
  - getSICoefficientsString
```
public abstract String getSICoefficientsString()
```
    Returns:
    
    the SI standard coefficients for this unit, e.g., kgm/s2 or m-2s2A or m^-2.s^2.A or m^-2s^2A (not necessarily normalized)
  - getSICoefficients
```
public final SICoefficients getSICoefficients()
```
    Returns:
    
    the SI coefficients
  - isBaseSIUnit
```
public final boolean isBaseSIUnit()
```
    Determine whether this unit is the standard unit.
    
    Returns:
    
    boolean; whether this is the standard unit or not
  - lookupUnitWithSICoefficients
```
public static Set<Unit<?>> lookupUnitWithSICoefficients(String normalizedSICoefficientsString)
```
    Parameters:
    
    normalizedSICoefficientsString - String; the normalized string (e.g., kg.m/s2) to look up
    
    Returns:
    
    a set with the Units belonging to this string, or an empty set when it does not exist
  - lookupOrCreateUnitWithSICoefficients
```
public static Set<Unit<?>> lookupOrCreateUnitWithSICoefficients(String normalizedSICoefficientsString)
```
    Parameters:
    
    normalizedSICoefficientsString - the normalized string (e.g., kg.m/s2) to look up
    
    Returns:
    
    a set of Units belonging to this string, or a set with a new unit when it does not yet exist
  - lookupOrCreateSIUnitWithSICoefficients
```
public static SIUnit lookupOrCreateSIUnitWithSICoefficients(String normalizedSICoefficientsString)
```
    Parameters:
    
    normalizedSICoefficientsString - String; the normalized string (e.g., kg.m/s2) to look up
    
    Returns:
    
    the Unit belonging to this string, or a new unit when it does not yet exist
  - toString
```
public final String toString()
```
    Overrides:
    
    toString in class Object
  - generateHashCode
```
public final int generateHashCode()
```
    Generate a hashCode for caching.
    
    Returns:
    
    a hashCode that is consistent with the equals() method.
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - equals
```
public boolean equals(Object obj)
```
    Overrides:
    
    equals in class Object
  - equalsIgnoreNaming
```
public abstract boolean equalsIgnoreNaming(Object obj)
```
    Test if two units are the same, except for the name and abbreviation. This means for instance that for the MassUnits METRIC_TON and MEGAGRAM (both 1000 kg) equals(...) will yield false, but equalsIgnoreNaming will yield true.
    
    Parameters:
    
    obj - Object; the object to compare with
    
    Returns:
    
    true if the two units are the same numerically, except for the naming and/or abbreviation

Class Unit<U extends Unit<U>>

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

STANDARD_UNITS

Constructor Detail

Unit

Unit

Unit

Unit

Method Detail

isLocalizable

getUnits

getAllUnitsOfThisType

getName

getDefaultLocaleName

getAbbreviation

getDefaultLocaleAbbreviation

getAbbreviationKey

getTextualRepresentations

getDefaultLocaleTextualRepresentations

getDefaultTextualRepresentation

getDefaultLocaleTextualRepresentation

getScale

getUnitSystem

getStandardUnit

getSICoefficientsString

getSICoefficients

isBaseSIUnit

lookupUnitWithSICoefficients

lookupOrCreateUnitWithSICoefficients

lookupOrCreateSIUnitWithSICoefficients

toString

generateHashCode

hashCode

equals

equalsIgnoreNaming