Quantity

java.lang.Object
- org.salespointframework.core.quantity.Quantity

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.lang.Comparable<Quantity>

Direct Known Subclasses:

Money, Units
```
public class Quantity
extends java.lang.Object
implements java.lang.Comparable<Quantity>, java.io.Serializable, java.lang.Cloneable
```
The Quantity class represents an amount of something. 'Something' is specified using a Metric. A RoundingStrategy accommodates amounts that do not fit the value set of a given metric (Think of money: 0.0001€ has no meaning in the real world). The roundingStrategy is applied to amount in the class constructor. This way, every instance has a valid amount. To allow arithmetic operations on Quantity objects and instances of subclasses of Quantity to return the correct type (and thus avoiding casts), Quantity instances are immutable and all subclasses of Quantity have to be immutable or implement a suitable clone()-method.

Author:

Hannes Weisbach

See Also:
Serialized Form

Constructor Summary

Constructors
Constructor and Description
`Quantity(java.math.BigDecimal amount, Metric metric, RoundingStrategy roundingStrategy)` Parameterized class constructor.
`Quantity(double amount, Metric metric, RoundingStrategy roundingStrategy)` Translates a `double` to a `Quantity`.
`Quantity(float amount, Metric metric, RoundingStrategy roundingStrategy)` Translates a `float` to a `Quantity`.
`Quantity(int amount, Metric metric, RoundingStrategy roundingStrategy)` Translates an `int` to a `Quantity`.
`Quantity(long amount, Metric metric, RoundingStrategy roundingStrategy)` Translates a `long` to a `Quantity`.

Method Summary

Methods
Modifier and Type	Method and Description
`<T extends Quantity> T`	`add(T quantity)` Sums two quantities up.
`java.lang.Object`	`clone()`
`int`	`compareTo(Quantity o)`
`<T extends Quantity> T`	`divide(T quantity)` Divides this by another quantity.
`boolean`	`equals(java.lang.Object obj)`
`java.math.BigDecimal`	`getAmount()` Returns the `amount` of this as `float`.
`Metric`	`getMetric()` Returns the `metric` associated with this `Quantity`.
`RoundingStrategy`	`getRoundingStrategy()` Returns the `RoundingStrategy` of this `Quantity`.
`boolean`	`greaterThan(Quantity other)` Compares Quantities
`int`	`hashCode()`
`boolean`	`isNegative()` Check if this quantity is negative
`boolean`	`lessThan(Quantity other)` Compares Quantities
`<T extends Quantity> T`	`multiply(T quantity)` Multiplies two quantities.
`<T extends Quantity> T`	`subtract(T quantity)` Subtracts a quantity from this.
`java.lang.String`	`toString()`

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

- Constructor Detail
  - Quantity
```
public Quantity(java.math.BigDecimal amount,
        Metric metric,
        RoundingStrategy roundingStrategy)
```
    Parameterized class constructor. amount is immediately rounded using the supplied roundingStrategy.
    
    Parameters:
    amount - amount represented by this Quantity
    metric - metric used for this Quantity
    roundingStrategy - roundingStrategy to be used with this Quantity
  - Quantity
```
public Quantity(int amount,
        Metric metric,
        RoundingStrategy roundingStrategy)
```
    Translates an int to a Quantity. The Integer is rounded according to the supplied RoudingStrategy.
    
    Parameters:
    amount - int value to be converted to Quantity
    metric - metric to be used with this Quantity
    roundingStrategy - roudingStrategy to be used with this Quantity
  - Quantity
```
public Quantity(long amount,
        Metric metric,
        RoundingStrategy roundingStrategy)
```
    Translates a long to a Quantity.
    
    Parameters:
    amount - long value to be converted to a Quantity
    metric - metric to be used with this Quantity
    roundingStrategy - roundingStrategy to be used with this Quantity
  - Quantity
```
public Quantity(float amount,
        Metric metric,
        RoundingStrategy roundingStrategy)
```
    Translates a float to a Quantity.
    
    Parameters:
    amount - float value to be converted to a Quantity
    metric - metric to be used with this Quantity
    roundingStrategy - roundingStrategy to be used with this Quantity
  - Quantity
```
public Quantity(double amount,
        Metric metric,
        RoundingStrategy roundingStrategy)
```
    Translates a double to a Quantity.
    
    Parameters:
    amount - double value to be converted to a Quantity
    metric - metric to be used with this Quantity
    roundingStrategy - roundingStrategy to be used with this Quantity
- Method Detail
  - getMetric
```
public Metric getMetric()
```
    Returns the metric associated with this Quantity.
    
    Returns:
    Metric of this Quantity.
  - getRoundingStrategy
```
public RoundingStrategy getRoundingStrategy()
```
    Returns the RoundingStrategy of this Quantity.
    
    Returns:
    RoundingStrategy of this Quantity.
  - getAmount
```
public java.math.BigDecimal getAmount()
```
    Returns the amount of this as float.
    
    Returns:
    the amount of this as float.
  - compareTo
```
public int compareTo(Quantity o)
```
    Specified by:
    
    compareTo in interface java.lang.Comparable<Quantity>
  - equals
```
public boolean equals(java.lang.Object obj)
```
    Overrides:
    
    equals in class java.lang.Object
  - isNegative
```
public boolean isNegative()
```
    Check if this quantity is negative
    
    Returns:
    true if the quantity is negative
  - lessThan
```
public boolean lessThan(Quantity other)
```
    Compares Quantities
    
    Parameters:
    other - Quantity to which this Quantity is to be compared.
    
    Returns:
    true if this quantity is less than the other quantity
  - greaterThan
```
public boolean greaterThan(Quantity other)
```
    Compares Quantities
    
    Parameters:
    other - Quantity to which this Quantity is to be compared.
    
    Returns:
    true if this quantity is greater than the other quantity
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object
  - hashCode
```
public final int hashCode()
```
    Overrides:
    
    hashCode in class java.lang.Object
  - clone
```
public java.lang.Object clone()
```
    Overrides:
    
    clone in class java.lang.Object
  - add
```
public <T extends Quantity> T add(T quantity)
```
    Sums two quantities up. The amount of this and quantity are added, and a new Quantity-instance is returned, representing the sum. The metric and rounding strategy of quantity are used for the new instance. No check is performed, whether the metrics of both quantities are compatible, i.e. it is possible to combine, say kg and s.
    To avoid casting, arithmetic methods are generic. If a sub class of Quantity is passed as parameter, the result will have the same type, as the parameter.
    
    Type Parameters:
    T - type of the parameter and returned object
    Parameters:
    quantity - Quantity to be added to this.
    
    Returns:
    a new Quantity object representing the sum of this and quantity.
  - subtract
```
public <T extends Quantity> T subtract(T quantity)
```
    Subtracts a quantity from this. The amount of this is subtracted by that of quantity, and a new Quantity-instance is returned, representing the difference. The metric and rounding strategy of quantity are used for the new instance. No check is performed, whether the metrics of both quantities are compatible, i.e. it is possible to combine, say kg and s.
    To avoid casting, arithmetic methods are generic. If a sub class of Quantity is passed as parameter, the result will have the same type, as the parameter.
    
    Type Parameters:
    T - type of the parameter and returned object
    Parameters:
    quantity - Quantity to be subtracted from this.
    
    Returns:
    a new Quantity object representing the difference of this and quantity.
  - multiply
```
public <T extends Quantity> T multiply(T quantity)
```
    Multiplies two quantities. The amount of this and quantity are multiplied, and a new Quantity-instance is returned, representing the product. The metric and rounding Strategy of this are used for the new instance. No check is performed, whether the metrics of both quantities are compatible, i.e. it is possible to combine, say kg and s.
    To avoid casting, arithmetic methods are generic. If a sub class of Quantity is passed as parameter, the result will have the same type, as the parameter.
    
    Type Parameters:
    T - type of the parameter and returned object
    Parameters:
    quantity - Quantity to be multiplied with this.
    
    Returns:
    a new Quantity object representing the product of this and quantity.
  - divide
```
public <T extends Quantity> T divide(T quantity)
```
    Divides this by another quantity. The amount of this the dividend, quantity the divisor, and a new Quantity-instance is returned as quotient. The metric and rounding Strategy of this are used for the new instance. No check is performed, whether the metrics of both quantities are compatible, i.e. it is possible to combine, say kg and s.
    To avoid casting, arithmetic methods are generic. If a sub class of Quantity is passed as parameter, the result will have the same type, as the parameter.
    
    Type Parameters:
    T - type of the parameter and returned object
    Parameters:
    quantity - Quantity to be used as divisor.
    
    Returns:
    a new Quantity object representing the quotient.

Class Quantity

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Quantity

Quantity

Quantity

Quantity

Quantity

Method Detail

getMetric

getRoundingStrategy

getAmount

compareTo

equals

isNegative

lessThan

greaterThan

toString

hashCode

clone

add

subtract

multiply

divide