Package org.djunits.quantity

Class Mass

java.lang.Object

java.lang.Number

org.djunits.quantity.def.Quantity<Mass>

org.djunits.quantity.Mass

All Implemented Interfaces:

Serializable, Comparable<Mass>, Additive<Mass>, Scalable<Mass>, Value<Mass>

public class Mass
extends Quantity<Mass>

Mass is the amount of matter in an object, measured in kilograms (kg).

Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See for project information https://djunits.org. The DJUNITS project is distributed under a three-clause BSD-style license.

Author:

Alexander Verbraeck

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Mass.Unit	Mass.Unit encodes the unit of the amount of matter in an object.

Field Summary

Fields

Modifier and Type	Field	Description
static final Mass	NaN	Constant with value NaN.
static final Mass	NEG_MAXVALUE	Constant with value -MAX_VALUE.
static final Mass	NEGATIVE_INFINITY	Constant with value NEGATIVE_INFINITY.
static final Mass	ONE	Constant with value one.
static final Mass	POS_MAXVALUE	Constant with value MAX_VALUE.
static final Mass	POSITIVE_INFINITY	Constant with value POSITIVE_INFINITY.
static final Mass	ZERO	Constant with value zero.

Fields inherited from class org.djunits.quantity.def.Quantity

si

Constructor Summary

Constructors

Constructor	Description
Mass(double valueInUnit, Mass.Unit unit)	Instantiate a Mass quantity expressed in the given unit.
Mass(double value, Mass.Unit displayUnit, boolean useSi)	Instantiate a Mass quantity with an SI or base value and a display unit.

Method Summary

Modifier and Type	Method	Description
Volume	divide(Density v)	Calculate the division of Mass and Density, which results in a Volume scalar.
FlowMass	divide(Duration v)	Calculate the division of Mass and Duration, which results in a FlowMass scalar.
Duration	divide(FlowMass v)	Calculate the division of Mass and FlowMass, which results in a Duration scalar.
Dimensionless	divide(Mass v)	Calculate the division of Mass and Mass, which results in a Dimensionless quantity.
Density	divide(Volume v)	Calculate the division of Mass and Volume, which results in a Density scalar.
Mass.Unit	getDisplayUnit()	Retrieve the unit of this Value.
Mass	instantiateSi(double siValue, UnitInterface<Mass> displayUnit)	Instantiate a quantity with an SI or base value, and a display unit.
Force	multiply(Acceleration v)	Calculate the multiplication of Mass and Acceleration, which results in a Force scalar.
FlowMass	multiply(Frequency v)	Calculate the multiplication of Mass and Frequency, which results in a FlowMass scalar.
Momentum	multiply(Speed v)	Calculate the multiplication of Mass and Speed, which results in a Momentum scalar.
static Mass	of(double valueInUnit, String unitString)	Returns a Mass based on a value and the textual representation of the unit, which can be localized.
static Mass	of(double valueInUnit, Mass.Unit unit)	Returns a Mass based on a value expressed in the unit.
static Mass	ofSi(double si)	Return a Mass instance based on an SI value.
static Mass	ofSi(double siValue, Mass.Unit displayUnit)	Instantiate a Mass quantity with an SI or base value and a display unit.
static Mass	valueOf(String text)	Returns a Mass representation of a textual representation of a value with a unit.

Methods inherited from class org.djunits.quantity.def.Quantity

abs, add, as, compareTo, divide, doubleValue, eq, eq0, equals, floatValue, format, format, format, ge, ge0, getInUnit, getInUnit, getName, gt, gt0, hashCode, instantiate, instantiateSi, interpolate, intValue, isRelative, le, le0, longValue, lt, lt0, max, mean, min, multiply, ne, ne0, negate, of, product, reciprocal, scaleBy, si, siUnit, subtract, sum, toString, valueOf

Methods inherited from class java.lang.Number

byteValue, shortValue

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.djunits.value.Scalable

divideBy

Methods inherited from interface org.djunits.value.Value

isAbsolute

Field Details

ZERO

public static final Mass ZERO

Constant with value zero.

ONE

public static final Mass ONE

Constant with value one.

NaN

public static final Mass NaN

Constant with value NaN.

POSITIVE_INFINITY

public static final Mass POSITIVE_INFINITY

Constant with value POSITIVE_INFINITY.

NEGATIVE_INFINITY

public static final Mass NEGATIVE_INFINITY

Constant with value NEGATIVE_INFINITY.

POS_MAXVALUE

public static final Mass POS_MAXVALUE

Constant with value MAX_VALUE.

NEG_MAXVALUE

public static final Mass NEG_MAXVALUE

Constant with value -MAX_VALUE.

Constructor Details

Mass

public Mass(double value,
 Mass.Unit displayUnit,
 boolean useSi)

Instantiate a Mass quantity with an SI or base value and a display unit.

Parameters:

value - the quantity value expressed in the SI or base unit

displayUnit - the display unit to use

useSi - use SI value when true, use value in unit when false

Mass

public Mass(double valueInUnit,
 Mass.Unit unit)

Instantiate a Mass quantity expressed in the given unit.

Parameters:

valueInUnit - the quantity value expressed in the given unit

unit - the unit of the value, also acts as the display unit

Method Details

ofSi

public static Mass ofSi(double si)

Return a Mass instance based on an SI value.

Parameters:

si - the si value

Returns:

the Mass instance based on an SI value

ofSi

public static Mass ofSi(double siValue,
 Mass.Unit displayUnit)

Instantiate a Mass quantity with an SI or base value and a display unit.

Parameters:

siValue - the quantity value expressed in the SI or base unit

displayUnit - the display unit to use

Returns:

the Mass instance based on an SI value with the given display unit

instantiateSi

public Mass instantiateSi(double siValue,
 UnitInterface<Mass> displayUnit)

Description copied from class: Quantity

Instantiate a quantity with an SI or base value, and a display unit.

Specified by:

instantiateSi in class Quantity<Mass>

Parameters:

siValue - the value expressed in the base (SI) unit

displayUnit - the display unit to use for the quantity

Returns:

a quantity with the given SI or base value, and the given display unit

valueOf

public static Mass valueOf(String text)

Returns a Mass representation of a textual representation of a value with a unit. The String representation that can be parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces are allowed, but not required, between the value and the unit.

Parameters:

text - the textual representation to parse into a Mass

Returns:

the Scalar representation of the value in its unit

Throws:

IllegalArgumentException - when the text cannot be parsed

NullPointerException - when the text argument is null

of

public static Mass of(double valueInUnit,
 Mass.Unit unit)

Returns a Mass based on a value expressed in the unit.

Parameters:

valueInUnit - the value, expressed in the given unit

unit - the unit of the value, also acts as the display unit

Returns:

ab Mass representation of the value in its unit

of

public static Mass of(double valueInUnit,
 String unitString)

Returns a Mass based on a value and the textual representation of the unit, which can be localized.

Parameters:

valueInUnit - the value, expressed in the unit as given by unitString

unitString - the textual representation of the unit

Returns:

the Scalar representation of the value in its unit

Throws:

IllegalArgumentException - when the unit cannot be parsed or is incorrect

NullPointerException - when the unitString argument is null

getDisplayUnit

public Mass.Unit getDisplayUnit()

Description copied from interface: Value

Retrieve the unit of this Value.

Specified by:

getDisplayUnit in interface Value<Mass>

Overrides:

getDisplayUnit in class Quantity<Mass>

Returns:

the unit of this Value

divide

public Dimensionless divide(Mass v)

Calculate the division of Mass and Mass, which results in a Dimensionless quantity.

Parameters:

v - quantity

Returns:

quantity as a division of Mass and Mass

divide

public Duration divide(FlowMass v)

Calculate the division of Mass and FlowMass, which results in a Duration scalar.

Parameters:

v - scalar

Returns:

scalar as a division of Mass and FlowMass

divide

public FlowMass divide(Duration v)

Calculate the division of Mass and Duration, which results in a FlowMass scalar.

Parameters:

v - scalar

Returns:

scalar as a division of Mass and Duration

multiply

public Force multiply(Acceleration v)

Calculate the multiplication of Mass and Acceleration, which results in a Force scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Mass and Acceleration

multiply

public FlowMass multiply(Frequency v)

Calculate the multiplication of Mass and Frequency, which results in a FlowMass scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Mass and Frequency

divide

public Volume divide(Density v)

Calculate the division of Mass and Density, which results in a Volume scalar.

Parameters:

v - scalar

Returns:

scalar as a division of Mass and Density

divide

public Density divide(Volume v)

Calculate the division of Mass and Volume, which results in a Density scalar.

Parameters:

v - scalar

Returns:

scalar as a division of Mass and Volume

multiply

public Momentum multiply(Speed v)

Calculate the multiplication of Mass and Speed, which results in a Momentum scalar.

Parameters:

v - scalar

Returns:

scalar as a multiplication of Mass and Speed