org.geotools.referencing.factory.epsg
Class AbstractEpsgFactory

Object
  AbstractFactory
      ReferencingFactory
          AbstractAuthorityFactory
              AbstractCachedAuthorityFactory
                  AbstractEpsgFactory

All Implemented Interfaces:

RegisterableService, BufferedFactory, Factory, AuthorityFactory, CRSAuthorityFactory, CSAuthorityFactory, DatumAuthorityFactory, CoordinateOperationAuthorityFactory

Direct Known Subclasses:

AccessDialectEpsgFactory, AnsiDialectEpsgFactory

public abstract class AbstractEpsgFactory
extends AbstractCachedAuthorityFactory

A coordinate reference system factory backed by the EPSG database tables.

The EPSG database is freely available at http://www.epsg.org. Current version of this class requires EPSG database version 6.6 or above.

This factory makes use of a provided ObjectCache, and may be deployed in stand aline fashion; or as a worker for a MultiEpsgFactory.

This class is abstract - please see the subclasses for dialect specific implementations:

• AccessDialectEpsgFactory
• AnsiDialectEpsgFactory
• OracleDialectEpsgFactory

These factories accepts names as well as numerical identifiers. For example "NTF (Paris) / France I" and "27581" both fetchs the same object. However, names may be ambiguous since the same name may be used for more than one object. This is the case of "WGS 84" for example. If such an ambiguity is found, an exception will be thrown. If names are not wanted as a legal EPSG code, subclasses can override the isPrimaryKey(java.lang.String) method.

Since:

2.4

Author:

Yann Cézard, Martin Desruisseaux (IRD), Rueben Schulz, Matthias Basler, Andrea Aime

Field Summary

protected DataSource

dataSource A DataSource to the EPSG database being used.

Fields inherited from class AbstractCachedAuthorityFactory

cache, factories

Fields inherited from class ReferencingFactory

LOGGER

Fields inherited from class AbstractFactory

hints, MAXIMUM_PRIORITY, MINIMUM_PRIORITY, NORMAL_PRIORITY, priority

Constructor Summary

AbstractEpsgFactory(Hints userHints)

AbstractEpsgFactory(Hints userHints, Connection connection)
Constructs an authority factory using the specified connection.

AbstractEpsgFactory(Hints userHints, DataSource dataSource)

Method Summary

protected abstract String	adaptSQL(String statement) Invoked when a new PreparedStatement is about to be created from a SQL string.
void	connect() Connect to the database in anticipation of of use.
void	disconnect() Disconnect from the database, and remain idle.
void	dispose() Disposes any resources hold by this object.
protected void	finalize() Invokes dispose() when this factory is garbage collected.
protected Set<String>	generateAuthorityCodes(Class type) Returns the set of authority codes of the given type.
CoordinateOperation	generateCoordinateOperation(String code) Returns a coordinate operation from a code.
CoordinateReferenceSystem	generateCoordinateReferenceSystem(String code) Returns a coordinate reference system from a code.
CoordinateSystem	generateCoordinateSystem(String code) Returns a coordinate system from a code.
CoordinateSystemAxis	generateCoordinateSystemAxis(String code) Returns a coordinate system axis from a code.
Datum	generateDatum(String code) Returns a datum from a code.
Ellipsoid	generateEllipsoid(String code) Returns an ellipsoid from a code.
Extent	generateExtent(String code) Returns an area of use.
Set	generateFromCoordinateReferenceSystemCodes(String sourceCode, String targetCode) Creates operations from coordinate reference system codes.
IdentifiedObject	generateObject(String code) Returns an arbitrary object from a code.
OperationMethod	generateOperationMethod(String code) Returns an operation method from a code.
ParameterDescriptor	generateParameterDescriptor(String code) Returns a parameter descriptor from a code.
PrimeMeridian	generatePrimeMeridian(String code) Returns a prime meridian, relative to Greenwich.
Unit<?>	generateUnit(String code) Returns an unit from a code.
Citation	getAuthority() Returns the authority for this EPSG database.
String	getBackingStoreDescription() Returns a description of the database engine.
protected Connection	getConnection() Access to the connection used by this EpsgFactory.
InternationalString	getDescriptionText(String code) Gets a description of the object corresponding to a code.
Map<RenderingHints.Key,?>	getImplementationHints() Returns the implementation hints for this factory.
protected boolean	isPrimaryKey(String code) Returns true if the specified code may be a primary key in some table.
protected void	shutdown(boolean active) Shutdown the database engine.

Methods inherited from class AbstractCachedAuthorityFactory

createCartesianCS, createCompoundCRS, createCoordinateOperation, createCoordinateReferenceSystem, createCoordinateSystem, createCoordinateSystemAxis, createCylindricalCS, createDatum, createDerivedCRS, createEllipsoid, createEllipsoidalCS, createEngineeringCRS, createEngineeringDatum, createFromCoordinateReferenceSystemCodes, createGeocentricCRS, createGeodeticDatum, createGeographicCRS, createImageCRS, createImageDatum, createObject, createPolarCS, createPrimeMeridian, createProjectedCRS, createSphericalCS, createTemporalCRS, createTemporalDatum, createTimeCS, createUnit, createVerticalCRS, createVerticalCS, createVerticalDatum, getAuthorityCodes, getIdentifiedObjectFinder, noSuchAuthorityCode, toKey, trimAuthority

Methods inherited from class AbstractAuthorityFactory

createExtent, createOperationMethod, createParameterDescriptor, noSuchAuthorityCode

Methods inherited from class ReferencingFactory

ensureNonNull, getVendor

Methods inherited from class AbstractFactory

addImplementationHints, equals, getPriority, hashCode, onDeregistration, onRegistration, toString

Methods inherited from class Object

clone, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface Factory

getVendor

Field Detail

dataSource

protected DataSource dataSource

A DataSource to the EPSG database being used.

Constructor Detail

AbstractEpsgFactory

public AbstractEpsgFactory(Hints userHints)
                    throws FactoryException

Throws:

FactoryException

AbstractEpsgFactory

public AbstractEpsgFactory(Hints userHints,
                           DataSource dataSource)

AbstractEpsgFactory

public AbstractEpsgFactory(Hints userHints,
                           Connection connection)

Constructs an authority factory using the specified connection.

Parameters:

userHints - The underlying factories used for objects creation.

connection - The connection to the underlying EPSG database.

Method Detail

getAuthority

public Citation getAuthority()

Returns the authority for this EPSG database. This authority will contains the database version in the edition attribute, together with the edition date.

Specified by:

getAuthority in interface AuthorityFactory

Specified by:

getAuthority in class AbstractCachedAuthorityFactory

Returns:

The organization reponsible for definition of the database.

getBackingStoreDescription

public String getBackingStoreDescription()
                                  throws FactoryException

Returns a description of the database engine.

Overrides:

getBackingStoreDescription in class AbstractAuthorityFactory

Returns:

The description of the underlying backing store, or null.

Throws:

FactoryException - if the database's metadata can't be fetched.

getImplementationHints

public Map<RenderingHints.Key,?> getImplementationHints()

Returns the implementation hints for this factory. The returned map contains all the values specified in subclass, with the addition of VERSION.

Specified by:

getImplementationHints in interface Factory

Overrides:

getImplementationHints in class AbstractFactory

Returns:

The map of hints, or an empty map if none.

generateAuthorityCodes

protected Set<String> generateAuthorityCodes(Class type)
                                      throws FactoryException

Returns the set of authority codes of the given type.

Specified by:

generateAuthorityCodes in class AbstractCachedAuthorityFactory

Parameters:

type - The spatial reference objects type (may be Object.class).

Returns:

The set of authority codes for spatial reference objects of the given type. If this factory doesn't contains any object of the given type, then this method returns an empty set.

Throws:

FactoryException - if access to the underlying database failed.

getDescriptionText

public InternationalString getDescriptionText(String code)
                                       throws FactoryException

Gets a description of the object corresponding to a code.

Specified by:

getDescriptionText in interface AuthorityFactory

Specified by:

getDescriptionText in class AbstractCachedAuthorityFactory

Parameters:

code - Value allocated by authority.

Returns:

A description of the object, or null if the object corresponding to the specified code has no description.

Throws:

NoSuchAuthorityCodeException - if the specified code was not found.

FactoryException - if the query failed for some other reason.

generateObject

public IdentifiedObject generateObject(String code)
                                throws FactoryException

Returns an arbitrary object from a code. The default implementation invokes one of AbstractCachedAuthorityFactory.createCoordinateReferenceSystem(java.lang.String), AbstractCachedAuthorityFactory.createCoordinateSystem(java.lang.String), AbstractCachedAuthorityFactory.createDatum(java.lang.String), AbstractCachedAuthorityFactory.createEllipsoid(java.lang.String), or AbstractCachedAuthorityFactory.createUnit(java.lang.String) methods according the object type.

Specified by:

generateObject in class AbstractCachedAuthorityFactory

Parameters:

code - The EPSG value.

Returns:

The object.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generateUnit

public Unit<?> generateUnit(String code)
                     throws FactoryException

Returns an unit from a code.

Specified by:

generateUnit in class AbstractCachedAuthorityFactory

Parameters:

code - Value allocated by authority.

Returns:

The unit object.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generateEllipsoid

public Ellipsoid generateEllipsoid(String code)
                            throws FactoryException

Returns an ellipsoid from a code.

Specified by:

generateEllipsoid in class AbstractCachedAuthorityFactory

Parameters:

code - The EPSG value.

Returns:

The ellipsoid object.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generatePrimeMeridian

public PrimeMeridian generatePrimeMeridian(String code)
                                    throws FactoryException

Returns a prime meridian, relative to Greenwich.

Specified by:

generatePrimeMeridian in class AbstractCachedAuthorityFactory

Parameters:

code - Value allocated by authority.

Returns:

The prime meridian object.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generateExtent

public Extent generateExtent(String code)
                      throws FactoryException

Returns an area of use.

Parameters:

code - Value allocated by authority.

Returns:

The area of use.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generateDatum

public Datum generateDatum(String code)
                    throws FactoryException

Returns a datum from a code.

Specified by:

generateDatum in class AbstractCachedAuthorityFactory

Parameters:

code - Value allocated by authority.

Returns:

The datum object.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generateCoordinateSystemAxis

public CoordinateSystemAxis generateCoordinateSystemAxis(String code)
                                                  throws FactoryException

Returns a coordinate system axis from a code.

Specified by:

generateCoordinateSystemAxis in class AbstractCachedAuthorityFactory

Parameters:

code - Value allocated by authority.

Throws:

NoSuchAuthorityCodeException - if the specified code was not found.

FactoryException - if the object creation failed for some other reason.

generateCoordinateSystem

public CoordinateSystem generateCoordinateSystem(String code)
                                          throws FactoryException

Returns a coordinate system from a code.

Specified by:

generateCoordinateSystem in class AbstractCachedAuthorityFactory

Parameters:

code - Value allocated by authority.

Returns:

The coordinate system object.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generateCoordinateReferenceSystem

public CoordinateReferenceSystem generateCoordinateReferenceSystem(String code)
                                                            throws FactoryException

Returns a coordinate reference system from a code.

Specified by:

generateCoordinateReferenceSystem in class AbstractCachedAuthorityFactory

Parameters:

code - Value allocated by authority.

Returns:

The coordinate reference system object.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generateParameterDescriptor

public ParameterDescriptor generateParameterDescriptor(String code)
                                                throws FactoryException

Returns a parameter descriptor from a code.

Parameters:

code - The parameter descriptor code allocated by EPSG authority.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generateOperationMethod

public OperationMethod generateOperationMethod(String code)
                                        throws FactoryException

Returns an operation method from a code.

Parameters:

code - The operation method code allocated by EPSG authority.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generateCoordinateOperation

public CoordinateOperation generateCoordinateOperation(String code)
                                                throws FactoryException

Returns a coordinate operation from a code. The returned object will either be a conversion or a transformation, depending on the code.

Specified by:

generateCoordinateOperation in class AbstractCachedAuthorityFactory

Parameters:

code - Value allocated by authority.

Returns:

The coordinate operation object.

Throws:

NoSuchAuthorityCodeException - if this method can't find the requested code.

FactoryException - if some other kind of failure occured in the backing store. This exception usually have SQLException as its cause.

generateFromCoordinateReferenceSystemCodes

public Set generateFromCoordinateReferenceSystemCodes(String sourceCode,
                                                      String targetCode)
                                               throws FactoryException

Creates operations from coordinate reference system codes. The returned set is ordered with the most accurate operations first.

Specified by:

generateFromCoordinateReferenceSystemCodes in class AbstractCachedAuthorityFactory

Parameters:

sourceCode - Coded value of source coordinate reference system.

targetCode - Coded value of target coordinate reference system.

Throws:

FactoryException - if the object creation failed.

adaptSQL

protected abstract String adaptSQL(String statement)

Invoked when a new PreparedStatement is about to be created from a SQL string. Since the EPSG database is available mainly in MS-Access format, SQL statements are formatted using some syntax specific to this particular database software (for example "SELECT * FROM [Coordinate Reference System]"). When prociding subclass targeting another database vendor, then this method should be overridden in order to adapt the local SQL syntax.

For example a subclass connecting to a PostgreSQL database could replace all spaces (" ") between watching braces ("[" and "]") by underscore ("_").

Parameters:

statement - The statement in MS-Access syntax.

Returns:

The SQL statement to use. The default implementation returns the string unchanged.

isPrimaryKey

protected boolean isPrimaryKey(String code)
                        throws FactoryException

Returns true if the specified code may be a primary key in some table. This method do not needs to checks any entry in the database. It should just checks from the syntax if the code looks like a valid EPSG identifier. The default implementation returns true if all non-space characters are digits.

When this method returns false, some createFoo(...) methods look for the code in the name column instead of the primary key column. This allows to accept the "NTF (Paris) / France I" string (for example) in addition to the "27581" primary key. Both should fetch the same object.

If this method returns true in all cases, then this factory never search for matching names. In such case, an appropriate exception will be thrown in createFoo(...) methods if the code is not found in the primary key column. Subclasses can overrides this method that way if this is the intended behavior.

Parameters:

code - The code the inspect.

Returns:

true if the code is probably a primary key.

Throws:

FactoryException - if an unexpected error occured while inspecting the code.

dispose

public void dispose()
             throws FactoryException

Disposes any resources hold by this object.

Overrides:

dispose in class AbstractCachedAuthorityFactory

Throws:

FactoryException - if an error occurred while closing the connection.

connect

public void connect()
             throws FactoryException

Connect to the database in anticipation of of use.

Throws:

FactoryException

disconnect

public void disconnect()
                throws FactoryException

Disconnect from the database, and remain idle. We will still keep our internal data structures, we are not going to hold onto a database connection unless we are going to be used.

Throws:

FactoryException

getConnection

protected Connection getConnection()
                            throws SQLException

Access to the connection used by this EpsgFactory. The connection will be created as needed.

Returns:

the connection

Throws:

SQLException

shutdown

protected void shutdown(boolean active)
                 throws SQLException

Shutdown the database engine. This method is invoked twice by ThreadedEpsgFactory at JVM shutdown: one time before the connection is closed, and a second time after. This shutdown hook is useful for embedded database engine starting a server process in addition to the client process. Just closing the connection is not enough for them. Example:

• HSQL database engine needs to execute a "SHUTDOWN" statement using the connection before it is closed.
• Derby database engine needs to instruct the driver manager after all connections have been closed.

The default implementation does nothing, which is sufficient for implementations connecting to a distant server (i.e. non-embedded database engine), for example MS-Access or PostgreSQL.

Parameters:

active - true if the connection is alive, or false otherwise. This method is invoked first with active set to true, then a second time with active set to false.

Throws:

SQLException - if this method failed to shutdown the database engine.

finalize

protected final void finalize()
                       throws Throwable

Invokes dispose() when this factory is garbage collected.

Overrides:

finalize in class Object

Throws:

Throwable - if an error occurred while closing the connection.