org.geotools.data.view
Class DefaultView

java.lang.Object
  org.geotools.data.view.DefaultView

All Implemented Interfaces:

FeatureSource

public class DefaultView

extends java.lang.Object

implements FeatureSource

Wrapper for FeatureSource constrained by a Query.

Support FeatureSource decorator that takes care of mapping a Query & FeatureSource with the schema and definition query configured for it.

Because GeoServer requires that attributes always be returned in the same order we need a way to smoothly inforce this. Could we use this class to do so?

WARNING: this class is a placeholder for ideas right now - it may not always impement FeatureSource.

Author:

Gabriel Rold?n

Field Summary

protected FeatureSource

source FeatureSource being served up

Constructor Summary

DefaultView(FeatureSource source, Query query)
Creates a new GeoServerFeatureSource object.

Method Summary

void	addFeatureListener(FeatureListener listener) Implement addFeatureListener.
static FeatureSource	create(FeatureSource source, Query query) Factory that make the correct decorator for the provided featureSource.
com.vividsolutions.jts.geom.Envelope	getBounds() Retrieves the total extent of this FeatureSource.
com.vividsolutions.jts.geom.Envelope	getBounds(Query query) Retrive the extent of the Query.
int	getCount(Query query) Adjust query and forward to source.
DataStore	getDataStore() Implement getDataStore.
FeatureCollection	getFeatures() Implement getFeatures.
FeatureCollection	getFeatures(Filter filter) Implement getFeatures.
FeatureCollection	getFeatures(Query query) Implement getFeatures.
FeatureType	getSchema() Implement getSchema.
protected Filter	makeDefinitionFilter(Filter filter) If a definition query has been configured for the FeatureTypeInfo, makes and return a new Filter that contains both the query's filter and the layer's definition one, by logic AND'ing them.
protected DefaultQuery	makeDefinitionQuery(Query query) Takes a query and adapts it to match re definitionQuery filter configured for a feature type.
void	removeFeatureListener(FeatureListener listener) Implement removeFeatureListener.

Methods inherited from class java.lang.Object

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

Field Detail

source

protected FeatureSource source

FeatureSource being served up

Constructor Detail

DefaultView

public DefaultView(FeatureSource source,
                   Query query)
            throws SchemaException

Creates a new GeoServerFeatureSource object.

Grabs the following from query:

• typeName - only used if client does not supply
• cs - only used if client does not supply
• csForce - only used if client does not supply
• filter - combined with client filter
• propertyNames - combined with client filter (indicate property names that *must* be included)

Schema is generated based on this information.

Parameters:

source - GeoTools2 FeatureSource

Throws:

SchemaException

Method Detail

create

public static FeatureSource create(FeatureSource source,
                                   Query query)
                            throws SchemaException

Factory that make the correct decorator for the provided featureSource.

This factory method is public and will be used to create all required subclasses. By comparison the constructors for this class have package visibiliy.

TODO: revisit this - I am not sure I want write access to views (especially if they do reprojection).

Returns:

@throws SchemaException

Throws:

SchemaException

makeDefinitionQuery

protected DefaultQuery makeDefinitionQuery(Query query)
                                    throws java.io.IOException

Takes a query and adapts it to match re definitionQuery filter configured for a feature type. It won't handle coordinate system changes

Grabs the following from query:

• typeName - only used if client does not supply
• filter - combined with client filter
• propertyNames - combined with client filter (indicate property names that *must* be included)

Parameters:

query - Query against this DataStore

Returns:

Query restricted to the limits of definitionQuery

Throws:

java.io.IOException - See DataSourceException

DataSourceException - If query could not meet the restrictions of definitionQuery

makeDefinitionFilter

protected Filter makeDefinitionFilter(Filter filter)
                               throws DataSourceException

If a definition query has been configured for the FeatureTypeInfo, makes and return a new Filter that contains both the query's filter and the layer's definition one, by logic AND'ing them.

Parameters:

filter - Origional user supplied Filter

Returns:

Filter adjusted to the limitations of definitionQuery

Throws:

DataSourceException - If the filter could not meet the limitations of definitionQuery

getDataStore

public DataStore getDataStore()

Implement getDataStore.

Description ...

Specified by:

getDataStore in interface FeatureSource

Returns:

@see org.geotools.data.FeatureSource#getDataStore()

addFeatureListener

public void addFeatureListener(FeatureListener listener)

Implement addFeatureListener.

Description ...

Specified by:

addFeatureListener in interface FeatureSource

Parameters:

listener -

See Also:

FeatureSource.addFeatureListener(org.geotools.data.FeatureListener)

removeFeatureListener

public void removeFeatureListener(FeatureListener listener)

Implement removeFeatureListener.

Description ...

Specified by:

removeFeatureListener in interface FeatureSource

Parameters:

listener -

See Also:

FeatureSource.removeFeatureListener(org.geotools.data.FeatureListener)

getFeatures

public FeatureCollection getFeatures(Query query)
                              throws java.io.IOException

Implement getFeatures.

Description ...

Specified by:

getFeatures in interface FeatureSource

Parameters:

query -

Returns:

@throws IOException

Throws:

java.io.IOException - For all data source errors.

See Also:

FeatureSource.getFeatures(org.geotools.data.Query)

getFeatures

public FeatureCollection getFeatures(Filter filter)
                              throws java.io.IOException

Implement getFeatures.

Description ...

Specified by:

getFeatures in interface FeatureSource

Parameters:

filter -

Returns:

@throws IOException

Throws:

java.io.IOException - For all data source errors.

See Also:

FeatureSource.getFeatures(org.geotools.filter.Filter)

getFeatures

public FeatureCollection getFeatures()
                              throws java.io.IOException

Implement getFeatures.

Description ...

Specified by:

getFeatures in interface FeatureSource

Returns:

@throws IOException

Throws:

java.io.IOException - For all data source errors.

See Also:

FeatureSource.getFeatures()

getSchema

public FeatureType getSchema()

Implement getSchema.

Description ...

Specified by:

getSchema in interface FeatureSource

Returns:

@see org.geotools.data.FeatureSource#getSchema()

getBounds

public com.vividsolutions.jts.geom.Envelope getBounds()
                                               throws java.io.IOException

Retrieves the total extent of this FeatureSource.

Please note this extent will reflect the provided definitionQuery.

Specified by:

getBounds in interface FeatureSource

Returns:

Extent of this FeatureSource, or null if no optimizations exist.

Throws:

java.io.IOException - If bounds of definitionQuery

getBounds

public com.vividsolutions.jts.geom.Envelope getBounds(Query query)
                                               throws java.io.IOException

Retrive the extent of the Query.

This method provides access to an optimized getBounds opperation. If no optimized opperation is available null will be returned.

You may still make use of getFeatures( Query ).getCount() which will return the correct answer (even if it has to itterate through all the results to do so.

Specified by:

getBounds in interface FeatureSource

Parameters:

query - User's query

Returns:

Extend of Query or null if no optimization is available

Throws:

java.io.IOException - If a problem is encountered with source

getCount

public int getCount(Query query)

Adjust query and forward to source.

This method provides access to an optimized getCount opperation. If no optimized opperation is available -1 will be returned.

You may still make use of getFeatures( Query ).getCount() which will return the correct answer (even if it has to itterate through all the results to do so).

Specified by:

getCount in interface FeatureSource

Parameters:

query - User's query.

Returns:

Number of Features for Query, or -1 if no optimization is available.