UnitDatabase

java.lang.Object
- org.unitConverter.unit.UnitDatabase

```
public final class UnitDatabase
extends java.lang.Object
```
A database of units, prefixes and dimensions, and their names.

Since:

2019-01-07, v0.1.0

Author:

Adrien Hopkins

Constructor Summary

Constructors
Constructor and Description

UnitDatabase()
Creates the UnitsDatabase.

Constructors
Constructor and Description
`UnitDatabase()` Creates the `UnitsDatabase`.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addDimension(java.lang.String name, ObjectProduct<BaseDimension> dimension)` Adds a unit dimension to the database.
`void`	`addPrefix(java.lang.String name, UnitPrefix prefix)` Adds a unit prefix to the database.
`void`	`addUnit(java.lang.String name, Unit unit)` Adds a unit to the database.
`boolean`	`containsDimensionName(java.lang.String name)` Tests if the database has a unit dimension with this name.
`boolean`	`containsPrefixName(java.lang.String name)` Tests if the database has a unit prefix with this name.
`boolean`	`containsUnitName(java.lang.String name)` Tests if the database has a unit with this name, taking prefixes into consideration
`java.util.Map<java.lang.String,ObjectProduct<BaseDimension>>`	`dimensionMap()`
`ObjectProduct<BaseDimension>`	`getDimension(java.lang.String name)` Gets a unit dimension from the database using its name.
`ObjectProduct<BaseDimension>`	`getDimensionFromExpression(java.lang.String expression)` Uses the database's data to parse an expression into a unit dimension
`UnitPrefix`	`getPrefix(java.lang.String name)` Gets a unit prefix from the database from its name
`UnitPrefix`	`getPrefixFromExpression(java.lang.String expression)` Gets a unit prefix from a prefix expression
`Unit`	`getUnit(java.lang.String name)` Gets a unit from the database from its name, looking for prefixes.
`Unit`	`getUnitFromExpression(java.lang.String expression)` Uses the database's unit data to parse an expression into a unit
`void`	`loadDimensionFile(java.io.File file)` Adds all dimensions from a file, using data from the database to parse them.
`void`	`loadUnitsFile(java.io.File file)` Adds all units from a file, using data from the database to parse them.
`java.util.Map<java.lang.String,UnitPrefix>`	`prefixMap()`
`java.lang.String`	`toString()`
`java.util.Map<java.lang.String,Unit>`	`unitMap()` Returns a map mapping unit names to units, including units with prefixes.
`java.util.Map<java.lang.String,Unit>`	`unitMapPrefixless()`

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

- Constructor Detail
  - UnitDatabase
```
public UnitDatabase()
```
    Creates the UnitsDatabase.
    
    Since:
    
    2019-01-10, v0.1.0
- Method Detail
  - addDimension
```
public void addDimension(java.lang.String name,
                         ObjectProduct<BaseDimension> dimension)
```
    Adds a unit dimension to the database.
    
    Parameters:
    
    name - dimension's name
    
    dimension - dimension to add
    
    Throws:
    
    java.lang.NullPointerException - if name or dimension is null
    
    Since:
    
    2019-03-14, v0.2.0
  - addPrefix
```
public void addPrefix(java.lang.String name,
                      UnitPrefix prefix)
```
    Adds a unit prefix to the database.
    
    Parameters:
    
    name - prefix's name
    
    prefix - prefix to add
    
    Throws:
    
    java.lang.NullPointerException - if name or prefix is null
    
    Since:
    
    2019-01-14, v0.1.0
  - addUnit
```
public void addUnit(java.lang.String name,
                    Unit unit)
```
    Adds a unit to the database.
    
    Parameters:
    
    name - unit's name
    
    unit - unit to add
    
    Throws:
    
    java.lang.NullPointerException - if unit is null
    
    Since:
    
    2019-01-10, v0.1.0
  - containsDimensionName
```
public boolean containsDimensionName(java.lang.String name)
```
    Tests if the database has a unit dimension with this name.
    
    Parameters:
    
    name - name to test
    
    Returns:
    
    if database contains name
    
    Since:
    
    2019-03-14, v0.2.0
  - containsPrefixName
```
public boolean containsPrefixName(java.lang.String name)
```
    Tests if the database has a unit prefix with this name.
    
    Parameters:
    
    name - name to test
    
    Returns:
    
    if database contains name
    
    Since:
    
    2019-01-13, v0.1.0
  - containsUnitName
```
public boolean containsUnitName(java.lang.String name)
```
    Tests if the database has a unit with this name, taking prefixes into consideration
    
    Parameters:
    
    name - name to test
    
    Returns:
    
    if database contains name
    
    Since:
    
    2019-01-13, v0.1.0
  - dimensionMap
```
public java.util.Map<java.lang.String,ObjectProduct<BaseDimension>> dimensionMap()
```
    Returns:
    
    a map mapping dimension names to dimensions
    
    Since:
    
    2019-04-13, v0.2.0
  - getDimension
```
public ObjectProduct<BaseDimension> getDimension(java.lang.String name)
```
    Gets a unit dimension from the database using its name.
    This method accepts exponents, like "L^3"
    
    Parameters:
    
    name - dimension's name
    
    Returns:
    
    dimension
    
    Since:
    
    2019-03-14, v0.2.0
  - getDimensionFromExpression
```
public ObjectProduct<BaseDimension> getDimensionFromExpression(java.lang.String expression)
```
    Uses the database's data to parse an expression into a unit dimension
    The expression is a series of any of the following:
    - The name of a unit dimension, which multiplies or divides the result based on preceding operators
    - The operators '*' and '/', which multiply and divide (note that just putting two unit dimensions next to each other is equivalent to multiplication)
    - The operator '^' which exponentiates. Exponents must be integers.
    Parameters:
    
    expression - expression to parse
    
    Throws:
    
    java.lang.IllegalArgumentException - if the expression cannot be parsed
    
    java.lang.NullPointerException - if expression is null
    
    Since:
    
    2019-04-13, v0.2.0
  - getPrefix
```
public UnitPrefix getPrefix(java.lang.String name)
```
    Gets a unit prefix from the database from its name
    
    Parameters:
    
    name - prefix's name
    
    Returns:
    
    prefix
    
    Since:
    
    2019-01-10, v0.1.0
  - getPrefixFromExpression
```
public UnitPrefix getPrefixFromExpression(java.lang.String expression)
```
    Gets a unit prefix from a prefix expression
    Currently, prefix expressions are much simpler than unit expressions: They are either a number or the name of another prefix
    
    Parameters:
    
    expression - expression to input
    
    Returns:
    
    prefix
    
    Throws:
    
    java.lang.IllegalArgumentException - if expression cannot be parsed
    
    java.lang.NullPointerException - if any argument is null
    
    Since:
    
    2019-01-14, v0.1.0
  - getUnit
```
public Unit getUnit(java.lang.String name)
```
    Gets a unit from the database from its name, looking for prefixes.
    
    Parameters:
    
    name - unit's name
    
    Returns:
    
    unit
    
    Since:
    
    2019-01-10, v0.1.0
  - getUnitFromExpression
```
public Unit getUnitFromExpression(java.lang.String expression)
```
    Uses the database's unit data to parse an expression into a unit
    The expression is a series of any of the following:
    - The name of a unit, which multiplies or divides the result based on preceding operators
    - The operators '*' and '/', which multiply and divide (note that just putting two units or values next to each other is equivalent to multiplication)
    - The operator '^' which exponentiates. Exponents must be integers.
    - A number which is multiplied or divided
    This method only works with linear units.
    Parameters:
    
    expression - expression to parse
    
    Throws:
    
    java.lang.IllegalArgumentException - if the expression cannot be parsed
    
    java.lang.NullPointerException - if expression is null
    
    Since:
    
    2019-01-07, v0.1.0
  - loadDimensionFile
```
public void loadDimensionFile(java.io.File file)
```
    Adds all dimensions from a file, using data from the database to parse them.
    Each line in the file should consist of a name and an expression (parsed by getDimensionFromExpression) separated by any number of tab characters.
    
    Allowed exceptions:
    - Anything after a '#' character is considered a comment and ignored.
    - Blank lines are also ignored
    - If an expression consists of a single exclamation point, instead of parsing it, this method will search the database for an existing unit. If no unit is found, an IllegalArgumentException is thrown. This is used to define initial units and ensure that the database contains them.
    Parameters:
    
    file - file to read
    
    Throws:
    
    java.lang.IllegalArgumentException - if the file cannot be parsed, found or read
    
    java.lang.NullPointerException - if file is null
    
    Since:
    
    2019-01-13, v0.1.0
  - loadUnitsFile
```
public void loadUnitsFile(java.io.File file)
```
    Adds all units from a file, using data from the database to parse them.
    Each line in the file should consist of a name and an expression (parsed by getUnitFromExpression) separated by any number of tab characters.
    
    Allowed exceptions:
    - Anything after a '#' character is considered a comment and ignored.
    - Blank lines are also ignored
    - If an expression consists of a single exclamation point, instead of parsing it, this method will search the database for an existing unit. If no unit is found, an IllegalArgumentException is thrown. This is used to define initial units and ensure that the database contains them.
    Parameters:
    
    file - file to read
    
    Throws:
    
    java.lang.IllegalArgumentException - if the file cannot be parsed, found or read
    
    java.lang.NullPointerException - if file is null
    
    Since:
    
    2019-01-13, v0.1.0
  - prefixMap
```
public java.util.Map<java.lang.String,UnitPrefix> prefixMap()
```
    Returns:
    
    a map mapping prefix names to prefixes
    
    Since:
    
    2019-04-13, v0.2.0
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    a string stating the number of units, prefixes and dimensions in the database
  - unitMap
```
public java.util.Map<java.lang.String,Unit> unitMap()
```
    Returns a map mapping unit names to units, including units with prefixes.
    The returned map is infinite in size if there is at least one unit and at least one prefix. If it is infinite, some operations that only work with finite collections, like converting name/entry sets to arrays, will throw an IllegalStateException.
    
    Specifically, the operations that will throw an IllegalStateException if the map is infinite in size are:
    - unitMap.entrySet().toArray() (either overloading)
    - unitMap.keySet().toArray() (either overloading)
    Because of ambiguities between prefixes (i.e. kilokilo = mega), the map's containsValue and values() methods currently ignore prefixes.
    Returns:
    
    a map mapping unit names to units, including prefixed names
    
    Since:
    
    2019-04-13, v0.2.0
  - unitMapPrefixless
```
public java.util.Map<java.lang.String,Unit> unitMapPrefixless()
```
    Returns:
    
    a map mapping unit names to units, ignoring prefixes
    
    Since:
    
    2019-04-13, v0.2.0

Class UnitDatabase

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

UnitDatabase

Method Detail

addDimension

addPrefix

addUnit

containsDimensionName

containsPrefixName

containsUnitName

dimensionMap

getDimension

getDimensionFromExpression

getPrefix

getPrefixFromExpression

getUnit

getUnitFromExpression

loadDimensionFile

loadUnitsFile

prefixMap

toString

unitMap

unitMapPrefixless