Package org.geotools.referencing.factory.epsg

Authority factories for the EPSG database.

See:
Description

Interface Summary

DataSource

A marker interface for data source to an EPSG database.

Class Summary

AccessDataSource	Connection to the EPSG database in MS-Access format using JDBC-ODBC bridge.
DefaultFactory	The default EPSG factory to be registered in FactoryFinder.
FactoryUsingAnsiSQL	An EPSG factory for the database generated by SQL scripts rather than the MS-Access one.
FactoryUsingOracleSQL	An EPSG factory suitable for Oracle SQL syntax.
FactoryUsingSQL	Default implementation for a coordinate reference system factory backed by the EPSG database.
FactoryUsingWKT	Implementation for a coordinate reference system authority factory backed by the EPSG property file.
HSQLDataSource	Connection to the EPSG database in HSQL database engine format using JDBC.
PostgreDataSource	Connection to the EPSG database in PostgreSQL database engine using JDBC.
SimpleDataSource	Open a connection to an EPSG database using DriverManager.

Package org.geotools.referencing.factory.epsg Description

Authority factories for the EPSG database.

EPSG codes are numerical identifiers. For example "4326" is the EPSG identifier for the "WGS 84" geographic CRS. However, the default implementation accepts names as well as numeric identifiers. For example "NTF (Paris) / France I" and both fetchs the same object. Note that 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.

An EPSG authority factory is created using the following code:

CRSAuthorityFactory factory = FactoryFinder.getCRSAuthorityFactory("EPSG", null);

This package provides the general framework for accessing an EPSG database, but the actual connection to a database requires the existence of an EPSG plugin in the classpath. Otherwise, a FactoryNotFoundException will be thrown. Available plugins are:

Required software	Data source	Plugin / JAR file	Additional notes
MS-Access ODBC driver	AccessDataSource		See installation instructions
HSQL embedded database	HSQLDataSource		Note for module mainteners
PostgreSQL database	PostgreDataSource		Note for module mainteners

How to create a custom data source

For getting the EPSG factory to uses a custom connection, create some subclass that implements Geotools's DataSource interface. For example:

import org.postgresql.ds.PGSimpleDataSource;
import org.geotools.factory.Hints;
import org.geotools.referencing.factory.AbstractAuthorityFactory;
import org.geotools.referencing.factory.epsg.DataSource;

public MyDataSource extends PGSimpleDataSource implements DataSource {
    public MyDataSource() {
        setServerName("myserver.com");
        setDatabaseName("mydatabase");
    }

    public int getPriority() {
        return MAXIMUM_PRIORITY - 200;

    public AbstractAuthorityFactory createFactory(Hints hints) throws SQLException {
        return new FactoryUsingAnsiSQL(hints, getConnection());
    }
}

Then, declare this custom implementation in the following file (for uses by FactoryRegistry):

META-INF/services/org.geotools.referencing.factory.epsg.DataSource

Just providing a JAR file with the above-cited DataSource implementation and registration is suffisient for an application to connects automatically to the specified server (providing that the relevant JDBC driver is present, of course).

Registration with JNDI (usually J2EE)

Installation on Unix systems typically has a database software running on some server rather than the local machine. The administrator will probably have to download the SQL scripts from http://www.epsg.org and executes it in whatever database software they use (PostgreSQL, MySQL, Oracle, etc.). The connection parameters (server URL, user name, etc.) can be specified as a DataSource registered with a naming service based on Java Naming and Directory (JNDI) interfaces. Like databases, the naming service is typically located on some server. The data source name for the connection to the EPSG database is {@value}.

• For setting up a naming service (LDAP, NIS, etc.), see the JNDI tutorial.

• For an example of DataSource creation with different connection parameters than the default ones, see New data source implementations in the JDBC-ODBC bridge.

• For DataSource implementations targeting other database softwares, see their JDBC documentation. For example the PostgreSQL JDBC provides an basic implementation.