ucar.units.Factor Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of udunits Show documentation
Show all versions of udunits Show documentation
The ucar.units Java package is for decoding and encoding formatted unit specifications (e.g. "m/s"), converting numeric values between compatible units (e.g. between "m/s" and "knot"), and for performing arithmetic operations on units (e.g. dividing one unit by another, or raising a unit to a power).
The newest version!
/*
* Copyright (c) 1998-2018 University Corporation for Atmospheric Research/Unidata
* See LICENSE for license information.
*/
package ucar.units;
import javax.annotation.concurrent.Immutable;
import java.io.Serializable;
/**
* Provides support for a Base/exponent pair. Instances of this class are
* immutable.
*
* @author Steven R. Emmerson
*/
@Immutable
public final class Factor implements Serializable {
private static final long serialVersionUID = 1L;
/**
* The Base entity.
*
* @serial
*/
private final Base _base;
/**
* The exponent.
*
* @serial
*/
private final int _exponent;
/**
* Constructs from a Base. The exponent is set to unity.
*
* @param base
* The base entity.
*/
public Factor(final Base base) {
this(base, 1);
}
/**
* Constructs from a Factor and an exponent.
*
* @param factor
* The factor.
* @param exponent
* The exponent.
*/
public Factor(final Factor factor, final int exponent) {
this(factor.getBase(), exponent);
}
/**
* Constructs from a Base and an exponent.
*
* @param base
* The base entity.
* @param exponent
* The exponent.
*/
public Factor(final Base base, final int exponent) {
_base = base;
_exponent = exponent;
}
/**
* Returns the Base entity.
*
* @return The Base entity.
*/
public Base getBase() {
return _base;
}
/**
* Returns the identifier of the Base entity.
*
* @return The identifier of the Base entity (symbol or name).
*/
public String getID() {
return getBase().getID();
}
/**
* Returns the exponent of the Base entity.
*
* @return The exponent of the Base entity.
*/
public int getExponent() {
return _exponent;
}
/**
* Raises this Factor to a power.
*
* @param power
* The power by which to raise this Factor.
* @return The Factor resulting from raising this Factor to the given power.
*/
public Factor pow(final int power) {
return new Factor(getBase(), getExponent() * power);
}
/**
* Returns the string representation of this Factor.
*
* @return The string representation of this Factor.
*/
@Override
public final String toString() {
return getExponent() == 0
? ""
: getExponent() == 1
? getBase().toString()
: getBase().toString() + getExponent();
}
/**
* Indicates if this Factor is semantically identical to another object.
*
* @param object
* The object.
* @return true if and only if this Factor is semantically
* identical to object<
* /code>.
*/
@Override
public boolean equals(final Object object) {
boolean equals;
if (this == object) {
equals = true;
}
else if (!(object instanceof Factor)) {
equals = false;
}
else {
final Factor that = (Factor) object;
equals = getExponent() != that.getExponent()
? false
: getExponent() == 0 || getBase().equals(that.getBase());
}
return equals;
}
/**
* Returns the hash code of this instance.
*
* @return The hash code of this instance.
*/
@Override
public int hashCode() {
return getExponent() == 0
? getClass().hashCode()
: getExponent() ^ getBase().hashCode();
}
/**
* Indicates if this Factor is the reciprocal of another Factor.
*
* @param that
* The other factor.
* @return true if and only if this Factor is the reciprocal of
* that.
*/
public boolean isReciprocalOf(final Factor that) {
return getBase().equals(that.getBase())
&& getExponent() == -that.getExponent();
}
/**
* Indicates if this factor is dimensionless. A Factor is dimensionless if
* and only if the exponent is zero or the Base entity is dimensionless.
*
* @return true if and only if this Factor is dimensionless.
*/
public boolean isDimensionless() {
return getExponent() == 0 || getBase().isDimensionless();
}
}