org.geotools.data.jdbc
Class JDBCFeatureWriter

java.lang.Object
  org.geotools.data.jdbc.JDBCFeatureWriter

All Implemented Interfaces:

FeatureWriter

Direct Known Subclasses:

JDBCPSFeatureWriter, JDBCTextFeatureWriter

public class JDBCFeatureWriter

extends java.lang.Object

implements FeatureWriter

JDBCDataStore implementation of the FeatureWriter interface

Author:

aaime

Field Summary

protected boolean	closed
protected Feature	current
protected java.lang.Object[]	fidAttributes
protected FeatureListenerManager	listenerManager
protected Feature	live
protected QueryData	queryData
protected FeatureReader	reader

Constructor Summary

JDBCFeatureWriter(FeatureReader reader, QueryData queryData)

Method Summary

void	close() Release the underlying resources.
protected void	doInsert(MutableFIDFeature mutable) Inserts a feature into the database.
protected void	doUpdate(Feature live, Feature current)
FeatureType	getFeatureType() FeatureType this reader has been configured to create.
boolean	hasNext() Query whether this FeatureWriter has another Feature.
Feature	next() Reads a Feature from the underlying AttributeReader.
void	remove() Removes current Feature, must be called before hasNext.
protected boolean	useQueryDataForInsert() Returns true if QueryData is used to insert rows, false if some other means is used
void	write() Wrties the current Feature, must be called before hasNext.

Methods inherited from class java.lang.Object

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

Field Detail

queryData

protected QueryData queryData

reader

protected FeatureReader reader

live

protected Feature live

current

protected Feature current

listenerManager

protected FeatureListenerManager listenerManager

closed

protected boolean closed

fidAttributes

protected java.lang.Object[] fidAttributes

Constructor Detail

JDBCFeatureWriter

public JDBCFeatureWriter(FeatureReader reader,
                         QueryData queryData)

Method Detail

getFeatureType

public FeatureType getFeatureType()

Description copied from interface: FeatureWriter

FeatureType this reader has been configured to create.

Specified by:

getFeatureType in interface FeatureWriter

Returns:

FeatureType this writer has been configured to create.

See Also:

FeatureWriter.getFeatureType()

next

public Feature next()
             throws java.io.IOException

Description copied from interface: FeatureWriter

Reads a Feature from the underlying AttributeReader.

This method may return a Feature even though hasNext() returns false, this allows FeatureWriters to provide an ability to append content.

Specified by:

next in interface FeatureWriter

Returns:

Feature from Query, or newly appended Feature

Throws:

java.io.IOException - DOCUMENT ME!

See Also:

FeatureWriter.next()

useQueryDataForInsert

protected boolean useQueryDataForInsert()

Returns true if QueryData is used to insert rows, false if some other means is used

Returns:

remove

public void remove()
            throws java.io.IOException

Description copied from interface: FeatureWriter

Removes current Feature, must be called before hasNext.

FeatureWriters will need to allow all FeatureSources of the same typeName to issue a FeatureEvent event of type FeatureEvent.FEATURES_REMOVED when this method is called.

If this FeatureWriter is opperating against a Transaction FEATURES_REMOVED events should only be sent to FeatureSources operating on the same Transaction. When Transaction commit() is called other FeatureSources will be informed of the modifications.

When the current Feature has been provided as new content, this method "cancels" the add opperation (and notification needed).

Specified by:

remove in interface FeatureWriter

Throws:

java.io.IOException - DOCUMENT ME!

See Also:

FeatureWriter.remove()

write

public void write()
           throws java.io.IOException

Description copied from interface: FeatureWriter

Wrties the current Feature, must be called before hasNext.

FeautreWriters will need to allow FeatureSources of the same typeName to issue a FeatureEvent:

• FeatureEvent.FEATURES_ADDED: when next() has been called with hasNext() equal to false.
• FeatureEvent.FEATURES_MODIFIED: when next has been called with hasNext() equal to true and the resulting Feature has indeed been modified.

If this FeatureWriter is opperating against a Transaction the FEATURES_MODIFIED or FEATURES_ADDED events should only be sent to FeatureSources opperating on the same Transaction. When Transaction commit() is called other FeatureSources will be informed of the modifications.

If you have not called write() when you call hasNext() or next(), no modification will occur().

Specified by:

write in interface FeatureWriter

Throws:

java.io.IOException

See Also:

FeatureWriter.write()

doUpdate

protected void doUpdate(Feature live,
                        Feature current)
                 throws java.io.IOException,
                        java.sql.SQLException

Throws:

java.io.IOException

java.sql.SQLException

doInsert

protected void doInsert(MutableFIDFeature mutable)
                 throws java.io.IOException,
                        java.sql.SQLException

Inserts a feature into the database.

This method should both insert a Feature, and update its FID in case the FIDMapper works over database generated ids like autoincrement fields, sequences, and object ids.

Postgis needs to do this seperately. With updates it can just override the geometry stuff, using a direct sql update statement, but for inserts it can't update a row that doesn't exist yet.

Parameters:

mutable -

Throws:

java.io.IOException

java.sql.SQLException

hasNext

public boolean hasNext()
                throws java.io.IOException

Description copied from interface: FeatureWriter

Query whether this FeatureWriter has another Feature.

Please note: it is more efficient to construct your FeatureWriter with a Filer (to skip entries you do not want), than to force the creation of entire Features only to skip over them.

FeatureWriters that support append opperations will allow calls to next, even when haveNext() returns false.

Specified by:

hasNext in interface FeatureWriter

Returns:

true if an additional Feature is available.

Throws:

java.io.IOException - DOCUMENT ME!

See Also:

FeatureWriter.hasNext()

close

public void close()
           throws java.io.IOException

Description copied from interface: FeatureWriter

Release the underlying resources.

Specified by:

close in interface FeatureWriter

Throws:

java.io.IOException - if there there are problems releasing underlying resources, or possibly if close has been called (up to the implementation).

See Also:

FeatureWriter.close()