org.deegree.io.datastore.sde
Class SDEQueryHandler

java.lang.Object
  org.deegree.io.datastore.sde.AbstractSDERequestHandler
      org.deegree.io.datastore.sde.SDEQueryHandler

public class SDEQueryHandler
extends AbstractSDERequestHandler

Special QueryHandler implementation for the SDEDatastore.

Version:

$Revision: 12183 $

Author:

Christoph Pollmann, last edited by: $Author: rbezema $

Field Summary

protected Map<String,Feature>	featureMap key: feature id value, value: Feature
protected Set<FeatureId>	featuresInGeneration key: feature id of features that are generated or are in generation
protected PropertyPath[]	propertyNames requested properties of the feature type
protected MappedFeatureType	rootFeatureType requested feature type
protected SDEWhereBuilder	whereBuilder used to build the initial SELECT (especially the WHERE-clause)

Fields inherited from class org.deegree.io.datastore.sde.AbstractSDERequestHandler

aliasGenerator, conn, datastore, FT_COLUMN, FT_PREFIX

Constructor Summary

SDEQueryHandler(SDEDatastore datastore, TableAliasGenerator aliasGenerator, SDEConnection conn, MappedFeatureType[] rootFts, Query query)
Creates a new instance of SDEQueryHandler from the given parameters.

Method Summary

protected com.esri.sde.sdk.client.SeQuery	buildInitialSelect(String[] columns) Builds the initial SELECT statement.
protected Feature	extractFeature(FeatureId fid, MappedFeatureType featureType, Map<MappedPropertyType,Collection<PropertyPath>> requestedPropertyMap, Map<MappingField,Integer> mappingFieldsMap, Object[] resultValues) Extracts a feature from the values of a result set row.
protected FeatureId	extractFeatureId(MappedFeatureType ft, Map<MappingField,Integer> mappingFieldMap, Object[] resultValues) Extracts the feature id from the values of a result set row.
FeatureCollection	performQuery() Performs the associated Query against the datastore.
protected void	resolveXLinks()

Methods inherited from class org.deegree.io.datastore.sde.AbstractSDERequestHandler

buildColumnsMap, buildInitialFIDSelect, buildMappingFieldMap, determineAffectedFIDs, extractFeatureIds, getAliasGenerator, getConnection, getDatastore, getFeatureIdColumns

Methods inherited from class java.lang.Object

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

Field Detail

rootFeatureType

protected MappedFeatureType rootFeatureType

requested feature type

propertyNames

protected PropertyPath[] propertyNames

requested properties of the feature type

whereBuilder

protected SDEWhereBuilder whereBuilder

used to build the initial SELECT (especially the WHERE-clause)

featuresInGeneration

protected Set<FeatureId> featuresInGeneration

key: feature id of features that are generated or are in generation

featureMap

protected Map<String,Feature> featureMap

key: feature id value, value: Feature

Constructor Detail

SDEQueryHandler

public SDEQueryHandler(SDEDatastore datastore,
                       TableAliasGenerator aliasGenerator,
                       SDEConnection conn,
                       MappedFeatureType[] rootFts,
                       Query query)
                throws DatastoreException

Creates a new instance of SDEQueryHandler from the given parameters.

Parameters:

datastore - datastore that spawned this QueryHandler

aliasGenerator - used to generate unique aliases for the tables in the SELECT statements

conn - SDEConnection to execute the generated SELECT statements against

rootFts - queried feature types

query - Query to perform

Throws:

DatastoreException

Method Detail

performQuery

public FeatureCollection performQuery()
                               throws DatastoreException

Performs the associated Query against the datastore.

Returns:

collection of requested features

Throws:

DatastoreException

resolveXLinks

protected void resolveXLinks()
                      throws DatastoreException

Throws:

DatastoreException

buildInitialSelect

protected com.esri.sde.sdk.client.SeQuery buildInitialSelect(String[] columns)

Builds the initial SELECT statement.

This statement determines all feature ids that are affected by the filter, but also SELECTs all properties that are stored in the root feature type's table (to improve efficiency).

The statement is structured like this:

• SELECT
• comma-separated list of selected qualified fields
• FROM
• comma-separated list of tables and their aliases (this is needed to constrain the paths to selected XPath-PropertyNames)
• WHERE
• SQL representation of the Filter expression
• ORDER BY
• qualified sort criteria fields

Parameters:

columns -

Returns:

the initial query

extractFeature

protected Feature extractFeature(FeatureId fid,
                                 MappedFeatureType featureType,
                                 Map<MappedPropertyType,Collection<PropertyPath>> requestedPropertyMap,
                                 Map<MappingField,Integer> mappingFieldsMap,
                                 Object[] resultValues)
                          throws DatastoreException

Extracts a feature from the values of a result set row.

Parameters:

fid - feature id of the feature

featureType - feature type of the feature to be extracted

requestedPropertyMap - requested MappedPropertyTypes mapped to Collection of PropertyPaths

mappingFieldsMap - key class: MappingField, value class: Integer (this is the associated index in resultValues)

resultValues - all retrieved columns from one result set row

Returns:

the extracted feature

Throws:

DatastoreException

extractFeatureId

protected FeatureId extractFeatureId(MappedFeatureType ft,
                                     Map<MappingField,Integer> mappingFieldMap,
                                     Object[] resultValues)

Extracts the feature id from the values of a result set row.

Parameters:

ft - feature type for which the id shall be extracted

mappingFieldMap - key class: MappingField, value class: Integer (this is the associated index in resultValues)

resultValues - all retrieved columns from one result set row

Returns:

the feature id