org.geotools.referencing.factory.epsg

Class DirectEpsgFactory

Object

AbstractFactory

ReferencingFactory

AbstractAuthorityFactory

DirectAuthorityFactory

DirectEpsgFactory

All Implemented Interfaces:

Factory, RegistrableFactory, AuthorityFactory, CRSAuthorityFactory, CSAuthorityFactory, DatumAuthorityFactory, CoordinateOperationAuthorityFactory

Direct Known Subclasses:

FactoryUsingSQL

public abstract class DirectEpsgFactory
extends DirectAuthorityFactory
implements CRSAuthorityFactory, CSAuthorityFactory, DatumAuthorityFactory, CoordinateOperationAuthorityFactory

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 doesn't cache any result. Any call to a createFoo method will send a new query to the EPSG database. For caching, this factory should be wrapped in some buffered factory like ThreadedEpsgFactory.

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

Fields inherited from class DirectAuthorityFactory

factories

Fields inherited from class ReferencingFactory

LOGGER

Fields inherited from class AbstractFactory

hints, MAXIMUM_PRIORITY, MINIMUM_PRIORITY, NORMAL_PRIORITY, priority

Constructor Summary

Constructors

Constructor and Description
DirectEpsgFactory(Hints userHints, Connection connection) Constructs an authority factory using the specified connection.
DirectEpsgFactory(Hints userHints, DataSource dataSource) Constructs an authority factory using the specified connection.

Method Summary

Modifier and Type	Method and Description
protected abstract String	adaptSQL(String statement) Invoked when a new PreparedStatement is about to be created from a SQL string.
CoordinateOperation	createCoordinateOperation(String code) Returns a coordinate operation from a code.
CoordinateReferenceSystem	createCoordinateReferenceSystem(String code) Returns a coordinate reference system from a code.
CoordinateSystem	createCoordinateSystem(String code) Returns a coordinate system from a code.
CoordinateSystemAxis	createCoordinateSystemAxis(String code) Returns a coordinate system axis from a code.
Datum	createDatum(String code) Returns a datum from a code.
Ellipsoid	createEllipsoid(String code) Returns an ellipsoid from a code.
Extent	createExtent(String code) Returns an area of use.
Set<CoordinateOperation>	createFromCoordinateReferenceSystemCodes(String sourceCode, String targetCode) Creates operations from coordinate reference system codes.
IdentifiedObject	createObject(String code) Returns an arbitrary object from a code.
OperationMethod	createOperationMethod(String code) Returns an operation method from a code.
ParameterDescriptor	createParameterDescriptor(String code) Returns a parameter descriptor from a code.
PrimeMeridian	createPrimeMeridian(String code) Returns a prime meridian, relative to Greenwich.
Unit<?>	createUnit(String code) Returns an unit from a code.
void	dispose() Disposes any resources hold by this object.
protected void	finalize() Invokes dispose() when this factory is garbage collected.
Citation	getAuthority() Returns the authority for this EPSG database.
Set<String>	getAuthorityCodes(Class<? extends IdentifiedObject> type) Returns the set of authority codes of the given type.
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.
IdentifiedObjectFinder	getIdentifiedObjectFinder(Class<? extends IdentifiedObject> type) Returns a finder which can be used for looking up unidentified objects.
Map<RenderingHints.Key,?>	getImplementationHints() Returns the implementation hints for this factory.
String	getValidationQuery() Returns the current validation query
protected boolean	isConnectionValid(Connection conn) Tests if the connection is valid by running the user provided validation query, if any.
protected boolean	isPrimaryKey(String code) Returns true if the specified code may be a primary key in some table.
void	setValidationQuery(String validationQuery) Sets the query it's run before using connection and prepared statements in order to check the connection is still valid.
protected void	shutdown(boolean active) Shutdown the database engine.

Methods inherited from class AbstractAuthorityFactory

createCartesianCS, createCompoundCRS, createCylindricalCS, createDerivedCRS, createEllipsoidalCS, createEngineeringCRS, createEngineeringDatum, createGeocentricCRS, createGeodeticDatum, createGeographicCRS, createImageCRS, createImageDatum, createPolarCS, createProjectedCRS, createSphericalCS, createTemporalCRS, createTemporalDatum, createTimeCS, createVerticalCRS, createVerticalCS, createVerticalDatum, noSuchAuthorityCode, trimAuthority

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 CRSAuthorityFactory

createCompoundCRS, createDerivedCRS, createEngineeringCRS, createGeocentricCRS, createGeographicCRS, createImageCRS, createProjectedCRS, createTemporalCRS, createVerticalCRS

Methods inherited from interface CSAuthorityFactory

createCartesianCS, createCylindricalCS, createEllipsoidalCS, createPolarCS, createSphericalCS, createTimeCS, createVerticalCS

Methods inherited from interface DatumAuthorityFactory

createEngineeringDatum, createGeodeticDatum, createImageDatum, createTemporalDatum, createVerticalDatum

Methods inherited from interface Factory

getVendor

Constructor Detail

DirectEpsgFactory

public DirectEpsgFactory(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.

DirectEpsgFactory

public DirectEpsgFactory(Hints userHints,
                         DataSource dataSource)

Constructs an authority factory using the specified connection.

Parameters:

userHints - The underlying factories used for objects creation.

dataSource - The data source connecting 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 AbstractAuthorityFactory

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 DirectAuthorityFactory

Returns:

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

getAuthorityCodes

public Set<String> getAuthorityCodes(Class<? extends IdentifiedObject> type)
                              throws FactoryException

Returns the set of authority codes of the given type.

NOTE: This method returns a living connection to the underlying database. This means that the returned set can executes efficiently idioms like the following one:

getAuthorityCodes(typeothers)

But do not keep the returned reference for a long time. The returned set should stay valid even if retained for a long time (as long as this factory has not been disposed), but the existence of those long-living connections may prevent this factory to release some resources. If the set of codes is needed for a long time, copy their values in an other collection object.

Specified by:

getAuthorityCodes in interface AuthorityFactory

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

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.

createObject

public IdentifiedObject createObject(String code)
                              throws FactoryException

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

Specified by:

createObject in interface AuthorityFactory

Overrides:

createObject in class AbstractAuthorityFactory

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.

See Also:

AbstractAuthorityFactory.createCoordinateReferenceSystem(java.lang.String), AbstractAuthorityFactory.createDatum(java.lang.String), AbstractAuthorityFactory.createEllipsoid(java.lang.String), AbstractAuthorityFactory.createUnit(java.lang.String)

createUnit

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

Returns an unit from a code.

Specified by:

createUnit in interface CSAuthorityFactory

Overrides:

createUnit in class AbstractAuthorityFactory

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.

createEllipsoid

public Ellipsoid createEllipsoid(String code)
                          throws FactoryException

Returns an ellipsoid from a code.

Specified by:

createEllipsoid in interface DatumAuthorityFactory

Overrides:

createEllipsoid in class AbstractAuthorityFactory

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.

See Also:

AbstractAuthorityFactory.createGeodeticDatum(java.lang.String)

createPrimeMeridian

public PrimeMeridian createPrimeMeridian(String code)
                                  throws FactoryException

Returns a prime meridian, relative to Greenwich.

Specified by:

createPrimeMeridian in interface DatumAuthorityFactory

Overrides:

createPrimeMeridian in class AbstractAuthorityFactory

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.

See Also:

AbstractAuthorityFactory.createGeodeticDatum(java.lang.String)

createExtent

public Extent createExtent(String code)
                    throws FactoryException

Returns an area of use.

Overrides:

createExtent in class AbstractAuthorityFactory

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.

createDatum

public Datum createDatum(String code)
                  throws FactoryException

Returns a datum from a code.

Specified by:

createDatum in interface DatumAuthorityFactory

Overrides:

createDatum in class AbstractAuthorityFactory

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.

See Also:

AbstractAuthorityFactory.createGeodeticDatum(java.lang.String), AbstractAuthorityFactory.createVerticalDatum(java.lang.String), AbstractAuthorityFactory.createTemporalDatum(java.lang.String)

createCoordinateSystemAxis

public CoordinateSystemAxis createCoordinateSystemAxis(String code)
                                                throws FactoryException

Returns a coordinate system axis from a code.

Specified by:

createCoordinateSystemAxis in interface CSAuthorityFactory

Overrides:

createCoordinateSystemAxis in class AbstractAuthorityFactory

Parameters:

code - Value allocated by authority.

Returns:

The axis for the given code.

Throws:

NoSuchAuthorityCodeException - if the specified code was not found.

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

createCoordinateSystem

public CoordinateSystem createCoordinateSystem(String code)
                                        throws FactoryException

Returns a coordinate system from a code.

Specified by:

createCoordinateSystem in interface CSAuthorityFactory

Overrides:

createCoordinateSystem in class AbstractAuthorityFactory

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.

createCoordinateReferenceSystem

public CoordinateReferenceSystem createCoordinateReferenceSystem(String code)
                                                          throws FactoryException

Returns a coordinate reference system from a code.

Specified by:

createCoordinateReferenceSystem in interface CRSAuthorityFactory

Overrides:

createCoordinateReferenceSystem in class AbstractAuthorityFactory

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.

See Also:

AbstractAuthorityFactory.createGeographicCRS(java.lang.String), AbstractAuthorityFactory.createProjectedCRS(java.lang.String), AbstractAuthorityFactory.createVerticalCRS(java.lang.String), AbstractAuthorityFactory.createTemporalCRS(java.lang.String), AbstractAuthorityFactory.createCompoundCRS(java.lang.String)

createParameterDescriptor

public ParameterDescriptor createParameterDescriptor(String code)
                                              throws FactoryException

Returns a parameter descriptor from a code.

Overrides:

createParameterDescriptor in class AbstractAuthorityFactory

Parameters:

code - The parameter descriptor code allocated by EPSG authority.

Returns:

The coordinate reference system for the given code.

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.

createOperationMethod

public OperationMethod createOperationMethod(String code)
                                      throws FactoryException

Returns an operation method from a code.

Overrides:

createOperationMethod in class AbstractAuthorityFactory

Parameters:

code - The operation method code allocated by EPSG authority.

Returns:

The operation method for the given code.

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.

createCoordinateOperation

public CoordinateOperation createCoordinateOperation(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:

createCoordinateOperation in interface CoordinateOperationAuthorityFactory

Overrides:

createCoordinateOperation in class AbstractAuthorityFactory

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.

createFromCoordinateReferenceSystemCodes

public Set<CoordinateOperation> createFromCoordinateReferenceSystemCodes(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:

createFromCoordinateReferenceSystemCodes in interface CoordinateOperationAuthorityFactory

Overrides:

createFromCoordinateReferenceSystemCodes in class AbstractAuthorityFactory

Parameters:

sourceCode - Coded value of source coordinate reference system.

targetCode - Coded value of target coordinate reference system.

Returns:

Throws:

FactoryException - if the object creation failed.

getIdentifiedObjectFinder

public IdentifiedObjectFinder getIdentifiedObjectFinder(Class<? extends IdentifiedObject> type)
                                                 throws FactoryException

Returns a finder which can be used for looking up unidentified objects.

Overrides:

getIdentifiedObjectFinder in class AbstractAuthorityFactory

Parameters:

type - The type of objects to look for.

Returns:

A finder to use for looking up unidentified objects.

Throws:

FactoryException - if the finder can not be created.

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 AbstractAuthorityFactory

Throws:

FactoryException - if an error occured while closing the connection.

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 usefull 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 suffisient 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 occured while closing the connection.

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

isConnectionValid

protected boolean isConnectionValid(Connection conn)

Tests if the connection is valid by running the user provided validation query, if any. Subclasses may override with a more efficient connection checking method if needed. If the validation query is not set, the method returns true by default.

Parameters:

conn - The connection to be validated

Returns:

True if the connection is alive, false if it should be replaced

getValidationQuery

public String getValidationQuery()

Returns the current validation query

setValidationQuery

public void setValidationQuery(String validationQuery)

Sets the query it's run before using connection and prepared statements in order to check the connection is still valid. The query should hit the database, but be as fast as possible.