Geomajas GeoTools layer plug-in

In order to read data from a WFS, a GeoTools layer is required. Currently GeoTools has support for WFS 1.0 and 1.1, and support for WFS-T 1.0. As the GeoTools WFS plug-in is not by default part of the class path, you must add it to the class path manually. First things first, the XML configuration. There are 2 ways of configuring a WFS layer through the GeoTools layer. As Geomajas uses a GeoTools DataStore behind the screens, it is possible to configure this DataStore separately, and than attach it to the GeoTools layer. This would have the advantage of re-using the same GeoTools DataStore over multiple layers. Alternatively you can configure the required parameters directly within the Layer configuration.

In general, the following parameters can be configured:

Note that most of the parameters above are optional. Only the capabilities URL is required.

You can configure a WFS layer like this:

<bean name="anotherWfsLayer" class="org.geomajas.layer.geotools.GeoToolsLayer">
   <property name="parameters">
      <list>
         <bean class="org.geomajas.configuration.Parameter">
            <property name="name" value="WFSDataStoreFactory:GET_CAPABILITIES_URL" />
            <property name="value" value="http://www.some-wfs.com/ows?service=WFS&amp;VERSION&#61;1.0.0&amp;request&#61;GetCapabilities" />
         </bean>
         <bean class="org.geomajas.configuration.Parameter">
            <property name="name" value="WFSDataStoreFactory:TIMEOUT" />
            <property name="value" value="5000" />
         </bean>
      </list>
   </property>
   <property name="layerInfo" ref="blablaInfo" />
</bean> 

As said in the beginning of this section, the GeoTools WFS library needs to be added as a dependency in your project. When using Maven, you can add the following dependency:

<dependency>
  <groupId>org.geotools</groupId>
  <artifactId>gt-wfs</artifactId>
  <version>${geotools-version}</version>
</dependency>

Configuring a GeoTools layer that makes use of a PostGIS database, is again a question of using the correct parameters. As with other examples of using a GeoTools layer, there is the choice of configuring the GetoTools DataStore separately or not. By configuring the DataStore separately, it can be used by multiple layers. In the case of a database, this method would almost always be preferable.

In general, the following parameters can be configured:

Configuring a database layer using PostGIS can be done like this:

<bean name="myPostGisLayer" class="org.geomajas.layer.geotools.GeoToolsLayer">
   <property name="parameters">
      <list>
         <bean class="org.geomajas.configuration.Parameter">
            <property name="name" value="namespace" />
            <property name="value" value="postgis" />
         </bean>
         <bean class="org.geomajas.configuration.Parameter">
            <property name="name" value="dbtype" />
            <property name="value" value="postgis" />
         </bean>
         <bean class="org.geomajas.configuration.Parameter">
            <property name="name" value="database" />
            <property name="value" value="some_database" />
         </bean>
         <bean class="org.geomajas.configuration.Parameter">
            <property name="name" value="user" />
            <property name="value" value="some_user" />
         </bean>
         <bean class="org.geomajas.configuration.Parameter">
            <property name="name" value="passwd" />
            <property name="value" value="some_password" />
         </bean>
         <bean class="org.geomajas.configuration.Parameter">
            <property name="name" value="host" />
            <property name="value" value="localhost" />
         </bean>
         <bean class="org.geomajas.configuration.Parameter">
            <property name="name" value="port" />
            <property name="value" value="5432" />
         </bean>
      </list>
   </property>
   <property name="layerInfo" ref="blablaInfo" />
</bean> 

Don't forget to also add the necessary database driver libraries to your project. Here is an example that adds PostGIS drivers and GeoTools PostGIS plug-in to the pom.xml (when using Maven):

<dependency>
   <groupId>org.postgis</groupId>
   <artifactId>postgis-jdbc</artifactId>
   <version>1.1.6</version>
</dependency>
<dependency>
   <groupId>postgresql</groupId>
   <artifactId>postgresql</artifactId>
   <version>8.1-407.jdbc3</version>
</dependency>
<dependency>
   <groupId>org.geotools</groupId>
   <artifactId>gt-postgis</artifactId>
   <version>${geotools-version}</version>
</dependency>