org.geotools.appschema.jdbc

Class JoiningJDBCFeatureSource

Object

ContentFeatureSource

JDBCFeatureSource

JoiningJDBCFeatureSource

All Implemented Interfaces:

FeatureSource<SimpleFeatureType,SimpleFeature>, SimpleFeatureSource

public class JoiningJDBCFeatureSource
extends JDBCFeatureSource

This is where the magic happens. The Joining JDBC Feature Source is a "hacking" class rather than a proper subclass. It provides functionality for executing 'joining queries'. Because only simple features can be returned by the existing geotools database logic, these joins on the db are not used for linking the actual features together, but only for putting the simple features in a certain order; an order that will allow us to do the actual feature chaining faster when we are building the complex features, because the right features will already be lined up in the right order.

Author:

Niels Charlier (Curtin University of Technology)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	JoiningJDBCFeatureSource.JoiningFieldEncoder Field Encoder for converting Filters/Expressions to SQL, will encode table name with field.

Field Summary

Fields

Modifier and Type	Field and Description
static String	FOREIGN_ID
static String	PRIMARY_KEY

Fields inherited from class ContentFeatureSource

entry, hints, lock, query, queryCapabilities, schema, transaction

Constructor Summary

Constructors

Constructor and Description
JoiningJDBCFeatureSource(JDBCFeatureSource featureSource)
JoiningJDBCFeatureSource(JDBCFeatureStore featureStore)

Method Summary

Modifier and Type	Method and Description
protected void	addMultiValuedSort(String tableName, Set<String> orderByFields, JoiningQuery.QueryJoin join, StringBuffer sql)
protected Filter	aliasFilter(Filter filter, SimpleFeatureType featureType, String alias)
protected static String	createAlias(String typeName, Set<String> tableNames)
protected FilterToSQL	createFilterToSQL(SimpleFeatureType ft) Craete the filter to sql converter
protected FilterToSQL	createFilterToSQL(SimpleFeatureType ft, boolean usePreparedStatementParameters) Craete the filter to sql converter
void	encodeColumnName(String colName, String typeName, StringBuffer sql, Hints hints) Encode column name with table name included.
void	encodeColumnName2(String colName, String typeName, StringBuffer sql, Hints hints) Encode column name with table name included, but do not include schema name (for aliases)
protected void	encodeGeometryColumn(GeometryDescriptor gatt, String typeName, StringBuffer sql, Hints hints) Encoding a geometry column with respect to hints Supported Hints are provided by SQLDialect.addSupportedHints(Set)
protected int	getCountInternal(Query query) Calculates the number of features of a specified query.
protected SimpleFeatureType	getFeatureType(SimpleFeatureType origType, JoiningQuery query)
FeatureReader<SimpleFeatureType,SimpleFeature>	getJoiningReaderInternal(JdbcMultipleValue mv, JoiningQuery query) Gets a feature reader for a JDBC multivalued mapping.
protected FeatureReader<SimpleFeatureType,SimpleFeature>	getJoiningReaderInternal(JoiningQuery query)
protected FeatureReader<SimpleFeatureType,SimpleFeature>	getReaderInternal(Query query) Subclass method for returning a native reader from the datastore.
protected boolean	isOrUnionReplacementEnabled()
protected boolean	isPostgisDialect()
protected Query	joinQuery(Query query) Convenience method for joining a query with the definining query of the feature source.
protected Query	resolvePropertyNames(Query query) This method changes the query object so that all propertyName references are resolved to simple attribute names against the schema of the feature source.
String	selectSQL(SimpleFeatureType featureType, JoiningQuery query, AtomicReference<PreparedFilterToSQL> toSQLref) Generates a 'SELECT p1, p2, ...
String	selectSQL(SimpleFeatureType featureType, JoiningQuery query, AtomicReference<PreparedFilterToSQL> toSQLref, boolean isCount) Generates a 'SELECT p1, p2, ...
protected PreparedStatement	selectSQLPS(SimpleFeatureType featureType, JoiningQuery query, Connection cx) Generates a 'SELECT p1, p2, ...
protected void	sort(JoiningQuery query, StringBuffer sql, String[] aliases, Set<String> pkColumnNames) Creates ORDER BY for joining query, based on all the sortby's that are specified per joining table
protected void	sort(String typeName, String alias, SortBy[] sort, Set<String> orderByFields, StringBuffer sql) Create order by field for specific table name

Methods inherited from class JDBCFeatureSource

addHints, buildFeatureType, buildQueryCapabilities, canFilter, canLimit, canOffset, canRetype, canSort, canTransact, getBoundsInternal, getDataStore, getPrimaryKey, getState, handleVisitor, isExposePrimaryKeyColumns, setExposePrimaryKeyColumns

Methods inherited from class ContentFeatureSource

accepts, addFeatureListener, canEvent, canLock, canReproject, doLockInternal, doUnlockInternal, getAbsoluteSchema, getBounds, getBounds, getCount, getEntry, getFeatures, getFeatures, getFeatures, getInfo, getName, getQueryCapabilities, getReader, getReader, getReader, getSchema, getSupportedHints, getTransaction, getView, getView, isView, lockFeatures, lockFeatures, lockFeatures, processLock, removeFeatureListener, resolvePropertyNames, setFeatureLock, setTransaction, unLockFeatures, unLockFeatures, unLockFeatures

Methods inherited from class Object

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

Field Detail

FOREIGN_ID

public static final String FOREIGN_ID

See Also:

Constant Field Values

PRIMARY_KEY

public static final String PRIMARY_KEY

See Also:

Constant Field Values

Constructor Detail

JoiningJDBCFeatureSource

public JoiningJDBCFeatureSource(JDBCFeatureSource featureSource)
                         throws IOException

Throws:

IOException

JoiningJDBCFeatureSource

public JoiningJDBCFeatureSource(JDBCFeatureStore featureStore)
                         throws IOException

Throws:

IOException

Method Detail

encodeGeometryColumn

protected void encodeGeometryColumn(GeometryDescriptor gatt,
                                    String typeName,
                                    StringBuffer sql,
                                    Hints hints)
                             throws SQLException

Encoding a geometry column with respect to hints Supported Hints are provided by SQLDialect.addSupportedHints(Set)

Parameters:

hints - , may be null

Throws:

SQLException

sort

protected void sort(String typeName,
                    String alias,
                    SortBy[] sort,
                    Set<String> orderByFields,
                    StringBuffer sql)
             throws IOException,
                    SQLException

Create order by field for specific table name

Throws:

IOException

SQLException

addMultiValuedSort

protected void addMultiValuedSort(String tableName,
                                  Set<String> orderByFields,
                                  JoiningQuery.QueryJoin join,
                                  StringBuffer sql)
                           throws IOException,
                                  FilterToSQLException,
                                  SQLException

Throws:

IOException

FilterToSQLException

SQLException

sort

protected void sort(JoiningQuery query,
                    StringBuffer sql,
                    String[] aliases,
                    Set<String> pkColumnNames)
             throws IOException,
                    SQLException,
                    FilterToSQLException

Creates ORDER BY for joining query, based on all the sortby's that are specified per joining table

Throws:

IOException

SQLException

FilterToSQLException

encodeColumnName

public void encodeColumnName(String colName,
                             String typeName,
                             StringBuffer sql,
                             Hints hints)
                      throws SQLException

Encode column name with table name included.

Throws:

SQLException

encodeColumnName2

public void encodeColumnName2(String colName,
                              String typeName,
                              StringBuffer sql,
                              Hints hints)
                       throws SQLException

Encode column name with table name included, but do not include schema name (for aliases)

Throws:

SQLException

createFilterToSQL

protected FilterToSQL createFilterToSQL(SimpleFeatureType ft)

Craete the filter to sql converter

createFilterToSQL

protected FilterToSQL createFilterToSQL(SimpleFeatureType ft,
                                        boolean usePreparedStatementParameters)

Craete the filter to sql converter

createAlias

protected static String createAlias(String typeName,
                                    Set<String> tableNames)

selectSQL

public String selectSQL(SimpleFeatureType featureType,
                        JoiningQuery query,
                        AtomicReference<PreparedFilterToSQL> toSQLref)
                 throws SQLException,
                        IOException,
                        FilterToSQLException

Generates a 'SELECT p1, p2, ... FROM ... WHERE ...' prepared statement.

Parameters:

featureType - the feature type that the query must return (may contain less attributes than the native one)

query - the query to be run. The type name and property will be ignored, as they are supposed to have been already embedded into the provided feature type

toSQLref - atomic reference to a FilterToSQL able to works with PreparedStament parameters

Throws:

SQLException

IOException

FilterToSQLException

selectSQL

public String selectSQL(SimpleFeatureType featureType,
                        JoiningQuery query,
                        AtomicReference<PreparedFilterToSQL> toSQLref,
                        boolean isCount)
                 throws IOException,
                        SQLException,
                        FilterToSQLException

Generates a 'SELECT p1, p2, ... FROM ... WHERE ...' prepared statement.

Parameters:

featureType - the feature type that the query must return (may contain less attributes than the native one)

query - the query to be run. The type name and property will be ignored, as they are supposed to have been already embedded into the provided feature type

toSQLref - atomic reference to a FilterToSQL able to works with PreparedStament parameters

isCount - avoid the encoding of unnecessary SQL pieces when a count query is needed

Throws:

IOException

SQLException

FilterToSQLException

selectSQLPS

protected PreparedStatement selectSQLPS(SimpleFeatureType featureType,
                                        JoiningQuery query,
                                        Connection cx)
                                 throws SQLException,
                                        IOException,
                                        FilterToSQLException

Generates a 'SELECT p1, p2, ... FROM ... WHERE ...' prepared statement.

Parameters:

featureType - the feature type that the query must return (may contain less attributes than the native one)

query - the query to be run. The type name and property will be ignored, as they are supposed to have been already embedded into the provided feature type

cx - The database connection to be used to create the prepared statement

Throws:

SQLException

IOException

FilterToSQLException

getFeatureType

protected SimpleFeatureType getFeatureType(SimpleFeatureType origType,
                                           JoiningQuery query)
                                    throws IOException

Throws:

IOException

getJoiningReaderInternal

protected FeatureReader<SimpleFeatureType,SimpleFeature> getJoiningReaderInternal(JoiningQuery query)
                                                                           throws IOException

Throws:

IOException

getJoiningReaderInternal

public FeatureReader<SimpleFeatureType,SimpleFeature> getJoiningReaderInternal(JdbcMultipleValue mv,
                                                                               JoiningQuery query)
                                                                        throws IOException

Gets a feature reader for a JDBC multivalued mapping.

Throws:

IOException

getReaderInternal

protected FeatureReader<SimpleFeatureType,SimpleFeature> getReaderInternal(Query query)
                                                                    throws IOException

Description copied from class: ContentFeatureSource

Subclass method for returning a native reader from the datastore.

It is important to note that if the native reader intends to handle any of the following natively:

• reprojection
• filtering
• max feature limiting
• sorting
• locking
• transactions

Then it *must* set the corresponding flags to true:

• ContentFeatureSource.canReproject() - handles Query.getCoordinateSystemReproject() internally. Example would be PostGIS using Proj to handle reproejction internally
• ContentFeatureSource.canFilter() - handles Query#getFilter() internally.
• {@link #canLimit()} - handles {@link Query#getMaxFeatures()} and {@link Query#getStartIndex()} internally.
• {@link #canSort()} - handles {@link Query#getSortBy()} natively.
• {@link #canRetype()} - handles {@link Query#getProperties()} natively. Example would be only parsing the properties the user asks for from an XML file
• {@link #canLock()} - handles read-locks natively
• {@link #canTransact()} - handles transactions natively

Overrides:

getReaderInternal in class JDBCFeatureSource

Throws:

IOException

resolvePropertyNames

protected Query resolvePropertyNames(Query query)

Description copied from class: ContentFeatureSource

This method changes the query object so that all propertyName references are resolved to simple attribute names against the schema of the feature source.

For example, this method ensures that propertyName's such as "gml:name" are rewritten as simply "name".

Overrides:

resolvePropertyNames in class ContentFeatureSource

joinQuery

protected Query joinQuery(Query query)

Description copied from class: ContentFeatureSource

Convenience method for joining a query with the definining query of the feature source.

Overrides:

joinQuery in class ContentFeatureSource

aliasFilter

protected Filter aliasFilter(Filter filter,
                             SimpleFeatureType featureType,
                             String alias)

isPostgisDialect

protected boolean isPostgisDialect()

isOrUnionReplacementEnabled

protected boolean isOrUnionReplacementEnabled()

getCountInternal

protected int getCountInternal(Query query)
                        throws IOException

Description copied from class: ContentFeatureSource

Calculates the number of features of a specified query. Subclasses must implement this method. If the computation is not fast, it's possible to return -1.

Overrides:

getCountInternal in class JDBCFeatureSource

Throws:

IOException