visad.data.netcdf
Class QuantityDB

java.lang.Object
  visad.data.netcdf.QuantityDB

Direct Known Subclasses:

NetcdfQuantityDB, QuantityDBImpl

public abstract class QuantityDB
extends Object

Provides support for a database of quantities.

Author:

Steven R. Emmerson

Field Summary

static QuantityDB

emptyDB The empty quantity database.

Constructor Summary

QuantityDB()

Method Summary

void	add(Quantity quantity) Adds a given Quantity to the database.
abstract void	add(String name, Quantity quantity) Adds a given Quantity to the database under a given name.
abstract Quantity	get(String name) Returns the quantity in the database whose name matches a given name.
Quantity	get(String name, String unitSpec) Returns the quantity that matches the given name and unit.
abstract Quantity[]	get(Unit unit) Returns all quantities in the database whose default unit is convertible with a given unit.
abstract Iterator	nameIterator() Returns an iterator of the names in the database.
abstract Iterator	quantityIterator() Returns an iterator of the quantities in the database.

Methods inherited from class java.lang.Object

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

Field Detail

emptyDB

public static final QuantityDB emptyDB

The empty quantity database. This is useful if, for example, you do not want the netCDF import package to map incoming netCDF variables to canonical ones by, effectively, altering their names and units. This database cannot be altered.

Constructor Detail

QuantityDB

public QuantityDB()

Method Detail

get

public abstract Quantity get(String name)

Returns the quantity in the database whose name matches a given name.

Parameters:

name - The name of the quantity.

Returns:

The quantity in the loal database that matches name. Note that RETURN_VALUE.getName().equals(name) can be false due to aliasing.

get

public abstract Quantity[] get(Unit unit)

Returns all quantities in the database whose default unit is convertible with a given unit.

Parameters:

unit - The unit of the quantity.

Returns:

The quantities in the database whose unit is convertible with unit.

get

public Quantity get(String name,
                    String unitSpec)
             throws ParseException,
                    NoSuchUnitException,
                    UnitException,
                    VisADException

Returns the quantity that matches the given name and unit. If necessary, it creates the quantity and adds it to the database.

Parameters:

name - The name of the quantity.

unitSpec - The unit of the quantity.

Returns:

The quantity in the database that matches name and unit. Note that RETURN_VALUE.getName().equals(name) can be false due to aliasing and RETURN_VALUE. getDefaultUnit().equals(unit) can be false due to allowable unit conversion.

Throws:

ParseException - Couldn't decode unitSpec.

NoSuchUnitException - unitSpec not in unit database.

UnitException - The quantity already exists with an incompatible unit.

VisADException - Couldn't create necessary VisAD object.

add

public abstract void add(String name,
                         Quantity quantity)
                  throws VisADException

Adds a given Quantity to the database under a given name.

Parameters:

name - The name under which the quantity is to be added. May be an alias.

quantity - The quantity to be added.

Throws:

VisADException - Couldn't create necessary VisAD object.

add

public void add(Quantity quantity)
         throws VisADException

Adds a given Quantity to the database.

Parameters:

quantity - The quantity to be added. The quantity will be added under it own name.

Throws:

VisADException - Couldn't create necessary VisAD object.

quantityIterator

public abstract Iterator quantityIterator()

Returns an iterator of the quantities in the database.

nameIterator

public abstract Iterator nameIterator()

Returns an iterator of the names in the database.