org.mmbase.storage.implementation.database
Class PostgresqlLargeObjectStorageManager

java.lang.Object
  org.mmbase.storage.implementation.database.DatabaseStorageManager
      org.mmbase.storage.implementation.database.RelationalDatabaseStorageManager
          org.mmbase.storage.implementation.database.PostgresqlLargeObjectStorageManager

All Implemented Interfaces:

StorageManager<DatabaseStorageManagerFactory>

public class PostgresqlLargeObjectStorageManager
extends RelationalDatabaseStorageManager

This class is responsible for handling binary objects using the PostgreSQL LargeObject API.

Author:

E-J. van der Laan, Finalist IT Group

Nested Class Summary

Nested classes/interfaces inherited from class org.mmbase.storage.implementation.database.DatabaseStorageManager

DatabaseStorageManager.InputStreamBlob

Field Summary

Fields inherited from class org.mmbase.storage.implementation.database.DatabaseStorageManager

activeConnection, changes, factory, inTransaction, OBJ2TYPE_MAX_SIZE, sequenceKeys, transactionIsolation, typeCache

Constructor Summary

PostgresqlLargeObjectStorageManager()

Method Summary

protected void	delete(MMObjectNode node, MMObjectBuilder builder, List<CoreField> blobFileField, String tablename) Deletes all references LargeObjects and calls the overridden method in its super class afterwards.
protected void	deleteLargeObjects(MMObjectNode node, MMObjectBuilder builder, List<CoreField> blobFileField) Delete all binary objects stored as large object.
protected Connection	getActiveConnection() Get the active connection.
protected Blob	getBlobValue(ResultSet result, int index, CoreField field, boolean mayShorten) Replaces it super class method and calls getBlobValueFromLargeObject(ResultSet, int, CoreField, boolean) instead.
protected Blob	getBlobValueFromLargeObject(ResultSet result, int index, CoreField field, boolean mayShorten) Retrieves a Blob from the database using the PostgreSQL LargeObject API.
protected int	getJDBCtoField(int jdbcType, int mmbaseType) Returns Field.TYPE_BINARY independent of the jdbcType.
protected void	setBinaryValue(PreparedStatement statement, int index, Object objectValue, CoreField field, MMObjectNode node) Writes the binary objectValue to to a LargeObject and stores the resulting oid as long in the statement.

Methods inherited from class org.mmbase.storage.implementation.database.RelationalDatabaseStorageManager

change, create, delete, getVersion, simpleCreate, tablesInheritFields

Methods inherited from class org.mmbase.storage.implementation.database.DatabaseStorageManager

addToTableNameCache, appendDirectory, appendField, beginTransaction, change, change, change, change, checkFile, commit, commitChange, convertLegacyBinaryFiles, create, create, create, create, create, create, createIndex, createIndices, createKey, createSequence, createTable, delete, delete, delete, delete, deleteIndices, executeQuery, executeUpdate, executeUpdateCheckConnection, exists, exists, exists, exists, exists, fillNode, getBinaryFile, getBinaryValue, getBlobFromDatabase, getBlobValue, getBlobValue, getBooleanValue, getConstraintDefinition, getDateTimeValue, getFactory, getFieldDefinition, getFieldList, getFieldTypeDefinition, getInputStreamValue, getLogStartTime, getNode, getNodeType, getStringValue, getStringValue, getValue, getXMLValue, init, isBinaryColumnType, isNull, isPartOfBuilderDefinition, isVerified, logQuery, refresh, releaseActiveConnection, rollback, setBooleanValue, setDateTimeValue, setDecimalValue, setListValue, setNodeType, setNodeTypeLeaveRelations, setNodeTypeRememberRelations, setNodeValue, setNullValue, setNumericValue, setStringValue, setValue, setXMLValue, shorten, size, size, storeBinaryAsFile, unloadShortedFields, verify, verifyTables

Methods inherited from class java.lang.Object

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

Constructor Detail

PostgresqlLargeObjectStorageManager

public PostgresqlLargeObjectStorageManager()

Method Detail

delete

protected void delete(MMObjectNode node,
                      MMObjectBuilder builder,
                      List<CoreField> blobFileField,
                      String tablename)

Deletes all references LargeObjects and calls the overridden method in its super class afterwards. This method overrides its super class delete

Overrides:

delete in class DatabaseStorageManager

See Also:

DatabaseStorageManager.delete(MMObjectNode, MMObjectBuilder, List, String)

deleteLargeObjects

protected void deleteLargeObjects(MMObjectNode node,
                                  MMObjectBuilder builder,
                                  List<CoreField> blobFileField)

Delete all binary objects stored as large object. This excludes the binary fields stored as file. See DatabaseStorageManager.delete(MMObjectNode, MMObjectBuilder, List, String) for the arguments.

Parameters:

node -

builder -

blobFileField -

getActiveConnection

protected Connection getActiveConnection()
                                  throws SQLException

Get the active connection. This connection has auto-commit set to false always. This is required by the PostgreSQL LargeObject API.

Overrides:

getActiveConnection in class DatabaseStorageManager

Throws:

SQLException - if opening the connection failed

getBlobValue

protected Blob getBlobValue(ResultSet result,
                            int index,
                            CoreField field,
                            boolean mayShorten)
                     throws StorageException,
                            SQLException

Replaces it super class method and calls getBlobValueFromLargeObject(ResultSet, int, CoreField, boolean) instead.

Overrides:

getBlobValue in class DatabaseStorageManager

Parameters:

result - the resultset to retrieve the text from

index - the index of the text in the resultset, or -1 to retireiv from file (blobs).

field - the (MMBase) fieldtype. This value can be null

Returns:

the retrieved data, null if no binary data was stored

Throws:

StorageException - when data is incompatible or the function is not supported

SQLException - when a database error occurs

getBlobValueFromLargeObject

protected Blob getBlobValueFromLargeObject(ResultSet result,
                                           int index,
                                           CoreField field,
                                           boolean mayShorten)
                                    throws StorageException,
                                           SQLException

Retrieves a Blob from the database using the PostgreSQL LargeObject API.

Parameters:

result - ResultSet holding the current record to read.

index - index of the blob field in the record set.

field - Field data for the blob.

mayShorten - if a Blob place holder must be returned instead of the real blob.

Returns:

null, SHORTED_BLOB, or a InputStreamBlob containing the inputstream returned by the LargeObject API.

Throws:

StorageException - when no LargeObject can be found when it should exist.

SQLException - can be thrown when acquiring the LargeObjectManager fails.

getJDBCtoField

protected int getJDBCtoField(int jdbcType,
                             int mmbaseType)

Returns Field.TYPE_BINARY independent of the jdbcType. In all other case it returns the result of the super class method. This is required because PostgreSQL returns jdbcType.INTEGER for OID fields.

Overrides:

getJDBCtoField in class DatabaseStorageManager

setBinaryValue

protected void setBinaryValue(PreparedStatement statement,
                              int index,
                              Object objectValue,
                              CoreField field,
                              MMObjectNode node)
                       throws StorageException,
                              SQLException

Writes the binary objectValue to to a LargeObject and stores the resulting oid as long in the statement. If the node already existed the existing LargeObject is deleted before creating a new one.

Overrides:

setBinaryValue in class DatabaseStorageManager

Parameters:

statement - the prepared statement

index - the index of the field in the prepared statement

objectValue - the data (byte array) to store

field - the MMBase field, containing meta-information

node - the node that contains the data. Used to update this node if the database layer makes changes to the data (i.e. creating a default value for a non-null field that had a null value)

Throws:

StorageException - if the data is invalid or missing

SQLException - if an error occurred while filling in the fields