visad.data.units
Class UnitTable

java.lang.Object
  visad.data.units.UnitTable

All Implemented Interfaces:

Serializable, UnitsDB

Direct Known Subclasses:

DefaultUnitsDB

public class UnitTable
extends Object
implements UnitsDB, Serializable

Provides support for a table of units.

Author:

Steven R. Emmerson

See Also:

Serialized Form

Constructor Summary

UnitTable(int numNames)
Construct.

UnitTable(int numNames, int numSymbols)
Construct.

Method Summary

Unit	get(String name) Get a unit.
protected Unit	getByName(String name) Get a unit by name.
protected Unit	getBySymbol(String symbol) Get a unit by symbol.
Enumeration	getNameEnumeration() Get an enumeration of the unit names in the table.
Enumeration	getSymbolEnumeration() Get an enumeration of the unit symbols in the table.
Enumeration	getUnitEnumeration() Get an enumeration of the units in the table.
void	list() List the units in the database.
static void	main(String[] args) Test this class.
protected String	makePlural(String name) Returns the plural form of a name.
void	put(BaseUnit unit) Adds a base unit.
void	putName(String name, Unit unit) Adds a name and a unit to the name table.
void	putSymbol(String symbol, Unit unit) Adds a symbol and a unit to the symbol table.
String	toString() Return a string representation of this instance.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

UnitTable

public UnitTable(int numNames)
          throws IllegalArgumentException

Construct.

Parameters:

numNames - Anticipated minimum number of names in the database.

Throws:

IllegalArgumentException - numNames < 0.

UnitTable

public UnitTable(int numNames,
                 int numSymbols)
          throws IllegalArgumentException

Construct.

Parameters:

numNames - Anticipated minimum number of names in the database.

numSymbols - Anticipated minimum number of symbols in the database.

Throws:

IllegalArgumentException - numNames < 0 || numSymbols < 0 .

Method Detail

get

public Unit get(String name)

Get a unit.

Specified by:

get in interface UnitsDB

Parameters:

name - The exact name of the unit to be retrieved. If it is the empty string, then the dimensionless, unity unit will be returned.

Returns:

The unit of the matching entry or null if not found.

Requirements:

name is non-null.

getByName

protected Unit getByName(String name)

Get a unit by name.

Parameters:

name - The name of the unit to be retrieved. If it is the empty string, then the dimensionless, unity unit will be returned.

Returns:

The unit of the matching entry or null if not found.

Requirements:

name is non-null.

getBySymbol

protected Unit getBySymbol(String symbol)

Get a unit by symbol.

Parameters:

symbol - The exact symbol of the unit to be retrieved. If it is the empty string, then the dimensionless, unity unit will be returned.

Returns:

The unit of the matching entry or null if not found.

Requirements:

name is non-null.

put

public void put(BaseUnit unit)
         throws IllegalArgumentException

Adds a base unit.

Specified by:

put in interface UnitsDB

Parameters:

unit - The base unit to be added.

Throws:

IllegalArgumentException - The base unit argument is invalid.

makePlural

protected String makePlural(String name)

Returns the plural form of a name. Regular rules are used to generate the plural form.

Parameters:

name - The name.

Returns:

The plural form of the name.

putName

public void putName(String name,
                    Unit unit)

Adds a name and a unit to the name table.

Specified by:

putName in interface UnitsDB

Parameters:

name - The name to be added.

unit - The unit to be added.

Throws:

IllegalArgumentException - Invalid argument.

putSymbol

public void putSymbol(String symbol,
                      Unit unit)

Adds a symbol and a unit to the symbol table.

Specified by:

putSymbol in interface UnitsDB

Parameters:

symbol - The symbol to be added.

unit - The unit to be added.

Throws:

IllegalArgumentException - Invalid argument.

getNameEnumeration

public Enumeration getNameEnumeration()

Get an enumeration of the unit names in the table. The Object returned by nextElement() is a String.

Specified by:

getNameEnumeration in interface UnitsDB

getSymbolEnumeration

public Enumeration getSymbolEnumeration()

Get an enumeration of the unit symbols in the table. The Object returned by nextElement() is a String.

Specified by:

getSymbolEnumeration in interface UnitsDB

getUnitEnumeration

public Enumeration getUnitEnumeration()

Get an enumeration of the units in the table. The Object returned by nextElement() is a Unit.

Specified by:

getUnitEnumeration in interface UnitsDB

toString

public String toString()

Return a string representation of this instance.

Overrides:

toString in class Object

main

public static void main(String[] args)
                 throws Exception

Test this class.

Throws:

Exception - A problem occurred.

list

public void list()

List the units in the database.

Specified by:

list in interface UnitsDB