# Class EPSGFactory

Object
AbstractFactory
GeodeticAuthorityFactory
ConcurrentAuthorityFactory<EPSGDataAccess>
EPSGFactory

All Implemented Interfaces:
  `AutoCloseable, Localized, Printable, AuthorityFactory, CRSAuthorityFactory, CSAuthorityFactory, DatumAuthorityFactory, CoordinateOperationAuthorityFactory, Factory`

public class EPSGFactory extends ConcurrentAuthorityFactory<EPSGDataAccess> implements CRSAuthorityFactory, CSAuthorityFactory, DatumAuthorityFactory, CoordinateOperationAuthorityFactory, Localized
A geodetic object factory backed by the EPSG database. This class creates JDBC connections to the EPSG database when first needed using the `DataSource` specified at construction time. The geodetic objects are cached for reuse and the idle connections are closed after a timeout.

If no data source has been specified to the constructor, then `EPSGFactory` searches for a default data source in JNDI, or in the directory given by the `SIS_DATA` environment variable, or in the directory given by the `"derby​.system​.home"` property, in that order. See the package documentation for more information.

## EPSG dataset installation

This class tries to automatically detect the schema that contains the EPSG tables (see `SQLTranslator` for examples of tables to look for). If the tables are not found, then the `install(Connection)` method will be invoked for creating the EPSG schema. The `install(…)` method can perform its work only if the definition files are reachable on the module path, or if the directory containing the files have been specified.

## Data Access Object (DAO)

If there is no cached object for a given code, then `EPSGFactory` creates an `EPSGDataAccess` instance for performing the actual creation work. Developers who need to customize the geodetic object creation can override the `newDataAccess(Connection, SQLTranslator)` method in order to return their own `EPSGDataAccess` subclass.

Since:
  0.7
See Also:
  - `EPSGDataAccess`
  - `SQLTranslator`
  - List of authority codes

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `protected final CoordinateOperationFactory`
  `copFactory`
  The factory to use for creating `CoordinateOperation` instances from the properties read in the database.
  `protected final CRSFactory`
  `crsFactory`
  The factory to use for creating `CoordinateReferenceSystem` instances from the properties read in the database.
  `protected final CSFactory`
  `csFactory`
  The factory to use for creating `CoordinateSystem` instances from the properties read in the database.
  `protected final DataSource`
  `dataSource`
  The factory to use for creating `Connection`s to the EPSG database.
  `protected final DatumFactory`
  `datumFactory`
  The factory to use for creating `Datum` instances from the properties read in the database.
  `protected final MathTransformFactory`
  `mtFactory`
  The factory to use for creating `MathTransform` instances.
  `protected final NameFactory`
  `nameFactory`
  The factory to use for creating `GenericName` instances.

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `EPSGFactory(Map<String,?> properties)`
  Creates a factory using the given configuration.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `protected boolean`
  `canClose(EPSGDataAccess factory)`
  Returns `true` if the given Data Access Object (DAO) can be closed.
  `Set<String>`
  `getCodeSpaces()`
  Returns the namespace of EPSG codes.
  `Locale`
  `getLocale()`
  Returns the locale used by this factory for producing error messages.
  `void`
  `install(Connection connection)`
  Creates the EPSG schema in the database and populates the tables with geodetic definitions.
  `protected EPSGDataAccess`
  `newDataAccess()`
  Creates the factory which will perform the actual geodetic object creation work.
  `protected EPSGDataAccess`
  `newDataAccess(Connection connection, SQLTranslator translator)`
  Creates the factory which will perform the actual geodetic object creation from a given connection.

  ### Methods inherited from class ConcurrentAuthorityFactory

  `close, createCartesianCS, createCompoundCRS, createCoordinateOperation, createCoordinateReferenceSystem, createCoordinateSystem, createCoordinateSystemAxis, createCylindricalCS, createDatum, createDatumEnsemble, createDerivedCRS, createEllipsoid, createEllipsoidalCS, createEngineeringCRS, createEngineeringDatum, createExtent, createFromCoordinateReferenceSystemCodes, createGeocentricCRS, createGeodeticDatum, createGeographicCRS, createImageCRS, createImageDatum, createObject, createOperationMethod, createParameterDescriptor, createPolarCS, createPrimeMeridian, createProjectedCRS, createSphericalCS, createTemporalCRS, createTemporalDatum, createTimeCS, createUnit, createVerticalCRS, createVerticalCS, createVerticalDatum, getAuthority, getAuthorityCodes, getDescriptionText, getTimeout, newIdentifiedObjectFinder, normalizeCode, print, printCacheContent, setTimeout, toString`

  ### Methods inherited from class GeodeticAuthorityFactory

  `createObject, createParametricCRS, createParametricCS, createParametricDatum, getDescriptionText, trimNamespace`

  ### Methods inherited from class AbstractFactory

  `getVendor`

  ### Methods inherited from class Object

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

  ### Methods inherited from interface AuthorityFactory

  `createObject, getAuthority, getAuthorityCodes, getDescriptionText`

  ### Methods inherited from interface CoordinateOperationAuthorityFactory

  `createCoordinateOperation, createFromCoordinateReferenceSystemCodes, createOperationMethod`

  ### Methods inherited from interface CRSAuthorityFactory

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

  ### Methods inherited from interface CSAuthorityFactory

  `createCartesianCS, createCoordinateSystem, createCoordinateSystemAxis, createCylindricalCS, createEllipsoidalCS, createPolarCS, createSphericalCS, createTimeCS, createUnit, createVerticalCS`

  ### Methods inherited from interface DatumAuthorityFactory

  `createDatum, createEllipsoid, createEngineeringDatum, createGeodeticDatum, createImageDatum, createPrimeMeridian, createTemporalDatum, createVerticalDatum`

  ### Methods inherited from interface Factory

  `getVendor`

- ## Field Details

  - ### dataSource

    protected final DataSource dataSource
    The factory to use for creating `Connection`s to the EPSG database.

  - ### nameFactory

    protected final NameFactory nameFactory
    The factory to use for creating `GenericName` instances.

  - ### datumFactory

    protected final DatumFactory datumFactory
    The factory to use for creating `Datum` instances from the properties read in the database.

  - ### csFactory

    protected final CSFactory csFactory
    The factory to use for creating `CoordinateSystem` instances from the properties read in the database.

  - ### crsFactory

    protected final CRSFactory crsFactory
    The factory to use for creating `CoordinateReferenceSystem` instances from the properties read in the database.

  - ### copFactory

    protected final CoordinateOperationFactory copFactory
    The factory to use for creating `CoordinateOperation` instances from the properties read in the database.

  - ### mtFactory

    protected final MathTransformFactory mtFactory
    The factory to use for creating `MathTransform` instances. The math transforms are created as part of `CoordinateOperation` creation process.

- ## Constructor Details

  - ### EPSGFactory

    public EPSGFactory(Map<String,?> properties) throws UnavailableFactoryException
    Creates a factory using the given configuration. The properties recognized by this constructor are listed in the table below. Any property not listed below will be ignored by this constructor. All properties are optional and can `null` or omitted, in which case default values are used. Those default values are implementation-specific and may change in any future SIS version.

    Recognized properties
    Key | Value class | Description
    --- | --- | ---
    `dataSource` | `DataSource` | The factory to use for creating `Connection`s to the EPSG database.
    `nameFactory` | `NameFactory` | The factory to use for creating `GenericName` instances.
    `datumFactory` | `DatumAuthorityFactory` | The factory to use for creating `Datum` instances.
    `csFactory` | `CSAuthorityFactory` | The factory to use for creating `CoordinateSystem` instances.
    `crsFactory` | `CRSAuthorityFactory` | The factory to use for creating `CoordinateReferenceSystem` instances.
    `copFactory` | `CoordinateOperationAuthorityFactory` | The factory to use for creating `CoordinateOperation` instances.
    `mtFactory` | `MathTransformFactory` | The factory to use for creating `MathTransform` instances.
    `catalog` | `String` | The database catalog that contains the EPSG schema (see install).
    `schema` | `String` | The database schema that contains the EPSG tables (see install).
    `scriptProvider` | `InstallationScriptProvider` | A provider of SQL scripts to use if `EPSGFactory` needs to create the database.
    `showDeprecated` | `Boolean` | Whether the list of EPSG codes should includes deprecated codes.
    `locale` | `Locale` | The locale for producing error messages on a best effort basis.

    Default values

    - If no `dataSource` is specified, this constructor defaults to the search algorithm described in the package documentation.
    - If no `catalog` or `schema` is specified, `SQLTranslator` will try to auto-detect the schema that contains the EPSG tables.
    - If no `locale` is specified, this constructor defaults to the display locale.
    Parameters:
      `properties` - the data source, authority factories and other configuration properties, or `null` for the default values.
    Throws:
      `ClassCastException` - if a property value is not of the expected class.
      `IllegalArgumentException` - if a property value is invalid.
      `UnavailableFactoryException` - if an error occurred while creating the EPSG factory.

- ## Method Details

  - ### getCodeSpaces

    public Set<String> getCodeSpaces()
    Returns the namespace of EPSG codes.
    Overrides:
      `getCodeSpaces` in class `GeodeticAuthorityFactory`
    Returns:
      the `"EPSG"` string in a singleton map.

  - ### getLocale

    public Locale getLocale()
    Returns the locale used by this factory for producing error messages. This locale does not change the way data are read from the EPSG database.
    Specified by:
      `getLocale` in interface `Localized`
    Returns:
      the locale for error messages.

  - ### install

    public void install(Connection connection) throws UnavailableFactoryException
    Creates the EPSG schema in the database and populates the tables with geodetic definitions. This method is invoked automatically when `newDataAccess()` detects that the EPSG geodetic dataset is not installed. Users can also invoke this method explicitly if they wish to force the dataset installation.

    This method uses the following properties from the map specified at construction time:

    - `catalog`:
      a `String` giving the name of the database catalog where to create the EPSG schema. If non-null, that catalog shall exist prior this method call (this method does not create any catalog). If no catalog is specified or if the catalog is an empty string, then the EPSG schema will be created without catalog. If the database does not support catalogs in table definitions or in data manipulation, then this property is ignored.
    - `schema`:
      a `String` giving the name of the database schema where to create the EPSG tables. That schema shall not exist prior this method call. The schema will be created by this `install(…)` method. If the schema is an empty string, then the tables will be created without schema. If no schema is specified, then the default schema is `"EPSG"`. If the database does not support schemas in table definitions or in data manipulation, then this property is ignored.
    - `scriptProvider`:
      an `InstallationScriptProvider` giving the SQL scripts to execute for creating the EPSG schema. If no provider is specified, then this method searches on the module path (with `ServiceLoader`) for user-provided implementations of `InstallationScriptProvider`.

    #### Legal constraint

    The EPSG dataset cannot be distributed with Apache SIS for licensing reasons. Users need to either install the dataset manually (for example with the help of this method), or add on the module path a separated bundle such as the `org​.apache​.sis​.referencing​.epsg` module. See How to use EPSG geodetic dataset for more information.
    Parameters:
      `connection` - connection to the database where to create the EPSG schema.
    Throws:
      `UnavailableFactoryException` - if installation failed. The exception will have a `FileNotFoundException` cause if a SQL script has not been found (typically because a required resource is not on the module path), an `IOException` if an I/O error occurred while reading a SQL script, or a `SQLException` if an error occurred while writing to the database.
    See Also:
      - `InstallationScriptProvider`

  - ### newDataAccess

    protected EPSGDataAccess newDataAccess() throws FactoryException
    Creates the factory which will perform the actual geodetic object creation work. This method is invoked automatically when a new worker is required, either because the previous one has been disposed after its timeout or because a new one is required for concurrency.

    The default implementation performs the following steps:

    1. Gets a new connection from the `dataSource`.
    2. If this method is invoked for the first time, verifies if the EPSG tables exists. If the tables are not found, invokes `install(Connection)`.
    3. Delegates to `newDataAccess(Connection, SQLTranslator)`, which provides an easier overriding point for subclasses wanting to return a custom `EPSGDataAccess` instance.
    Specified by:
      `newDataAccess` in class `ConcurrentAuthorityFactory<EPSGDataAccess>`
    Returns:
      Data Access Object (DAO) to use in `createFoo(String)` methods.
    Throws:
      `FactoryException` - if the constructor failed to connect to the EPSG database. This exception usually has a `SQLException` as its cause.

  - ### newDataAccess

    protected EPSGDataAccess newDataAccess(Connection connection, SQLTranslator translator) throws SQLException
    Creates the factory which will perform the actual geodetic object creation from a given connection. This method is a convenience hook easier to override than `newDataAccess()` for subclasses wanting to return instances of their own `EPSGDataAccess` subclass. The default implementation is simply:

        return new EPSGDataAccess(this, connection, translator);

    Subclasses can override this method with a similar code but with `new EPSGDataAccess(…)` replaced by `new MyDataAccessSubclass(…)`.
    Parameters:
      `connection` - a connection to the EPSG database.
      `translator` - translator from the SQL statements hard-coded in `EPSGDataAccess` to SQL statements compatible with the actual EPSG database.
    Returns:
      Data Access Object (DAO) to use in `createFoo(String)` methods.
    Throws:
      `SQLException` - if an error occurred with the database connection.
    See Also:
      - `EPSGDataAccess(EPSGFactory, Connection, SQLTranslator)`

  - ### canClose

    protected boolean canClose(EPSGDataAccess factory)
    Returns `true` if the given Data Access Object (DAO) can be closed. This method is invoked automatically after the timeout if the given DAO has been idle during all that time. Returns `false` if a set returned by `EPSGDataAccess​.getAuthorityCodes(Class)` is still in use.
    Overrides:
      `canClose` in class `ConcurrentAuthorityFactory<EPSGDataAccess>`
    Parameters:
      `factory` - the Data Access Object which is about to be closed.
    Returns:
      `true` if the given Data Access Object can be closed.
    See Also:
      - `ConcurrentAuthorityFactory​.close()`