org.apache.ojb.broker.platforms
Class PlatformOracle9iImpl

java.lang.Object
  org.apache.ojb.broker.platforms.PlatformDefaultImpl
      org.apache.ojb.broker.platforms.PlatformOracleImpl
          org.apache.ojb.broker.platforms.PlatformOracle9iImpl

All Implemented Interfaces:

JoinSyntaxTypes, Platform

public class PlatformOracle9iImpl

extends PlatformOracleImpl

This class is a concrete implementation of Platform. Provides an implementation that works around some issues with Oracle in general and Oracle 9i's Thin driver in particular. NOTE: When using BEA WebLogic and BLOB/CLOB datatypes, the physical connection will be used causing WebLogic to mark it as "infected" and discard it when the logicical connection is closed. You can change this behavior by setting the RemoveInfectedConnectionsEnabled attribute on a connection pool. see WebLogic docs. Optimization: Oracle Batching (not standard JDBC batching) see http://technet.oracle.com/products/oracle9i/daily/jun07.html Optimization: Oracle Prefetching see http://otn.oracle.com/sample_code/tech/java/sqlj_jdbc/files/advanced/RowPrefetchSample/Readme.html Optimization: Oracle Statement Caching see http://otn.oracle.com/sample_code/tech/java/sqlj_jdbc/files/jdbc30/StmtCacheSample/Readme.html TODO: Optimization: use ROWNUM to minimize the effects of not having server side cursors see http://asktom.oracle.com/pls/ask/f?p=4950:8:::::F4950_P8_DISPLAYID:127412348064

Version:

CVS $Id: PlatformOracle9iImpl.java 364787 2005-04-26 03:41:37Z mkalen $

Author:

Matthew Baird, Martin Kalén, Contributions from: Erik Forkalsrud, Danilo Tommasina, Thierry Hanot, Don Lyon

See Also:

Platform, PlatformDefaultImpl, PlatformOracleImpl

Field Summary

Fields inherited from interface org.apache.ojb.broker.accesslayer.JoinSyntaxTypes

ORACLE_JOIN_SYNTAX, SQL92_JOIN_SYNTAX, SQL92_NOPAREN_JOIN_SYNTAX, SYBASE_JOIN_SYNTAX

Constructor Summary

PlatformOracle9iImpl()
Default constructor.

Method Summary

void	addBatch(java.sql.PreparedStatement stmt) Try Oracle update batching and call executeUpdate or revert to JDBC update batching.
void	afterStatementCreate(java.sql.Statement stmt) Performs platform-specific operations on each statement.
void	beforeBatch(java.sql.PreparedStatement stmt) Try Oracle update batching and call setExecuteBatch or revert to JDBC update batching.
int[]	executeBatch(java.sql.PreparedStatement stmt) Try Oracle update batching and call sendBatch or revert to JDBC update batching.
byte	getJoinSyntaxType() Get join syntax type for this RDBMS.
void	initializeJdbcConnection(JdbcConnectionDescriptor jcd, java.sql.Connection conn) Enables Oracle statement caching and row prefetching if supported by the JDBC-driver.
void	setObjectForStatement(java.sql.PreparedStatement ps, int index, java.lang.Object value, int sqlType) For objects beyond 4k, weird things happen in Oracle if you try to use "setBytes", so for all cases it's better to use setBinaryStream.

Methods inherited from class org.apache.ojb.broker.platforms.PlatformOracleImpl

createSequenceQuery, createSequenceQuery, dropSequenceQuery, nextSequenceQuery, prepareNextValProcedureStatement, registerOutResultSet

Methods inherited from class org.apache.ojb.broker.platforms.PlatformDefaultImpl

addPagingSql, afterStatementClose, beforeStatementClose, bindPagingParameters, bindPagingParametersFirst, changeAutoCommitState, concatenate, getEscapeClause, getLastInsertIdentityQuery, setNullForStatement, supportsBatchOperations, supportsMultiColumnCountDistinct, supportsPaging, useCountForResultsetSize

Methods inherited from class java.lang.Object

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

Constructor Detail

PlatformOracle9iImpl

public PlatformOracle9iImpl()

Default constructor.

Method Detail

initializeJdbcConnection

public void initializeJdbcConnection(JdbcConnectionDescriptor jcd,
                                     java.sql.Connection conn)
                              throws PlatformException

Enables Oracle statement caching and row prefetching if supported by the JDBC-driver.

Specified by:

initializeJdbcConnection in interface Platform

Overrides:

initializeJdbcConnection in class PlatformDefaultImpl

Parameters:

jcd - the OJB JdbcConnectionDescriptor (metadata) for the connection to be initialized

conn - the Connection-object (physical) to be initialized

Throws:

PlatformException

See Also:

PlatformDefaultImpl.initializeJdbcConnection(org.apache.ojb.broker.metadata.JdbcConnectionDescriptor, java.sql.Connection), Oracle TechNet Statement Caching Sample, Oracle TechNet Row Pre-fetch Sample

afterStatementCreate

public void afterStatementCreate(java.sql.Statement stmt)

Performs platform-specific operations on each statement.

Specified by:

afterStatementCreate in interface Platform

Overrides:

afterStatementCreate in class PlatformOracleImpl

Parameters:

stmt - the statement just created

beforeBatch

public void beforeBatch(java.sql.PreparedStatement stmt)
                 throws PlatformException

Try Oracle update batching and call setExecuteBatch or revert to JDBC update batching. See 12-2 Update Batching in the Oracle9i JDBC Developer's Guide and Reference.

Specified by:

beforeBatch in interface Platform

Overrides:

beforeBatch in class PlatformDefaultImpl

Parameters:

stmt - the prepared statement to be used for batching

Throws:

PlatformException - upon JDBC failure

addBatch

public void addBatch(java.sql.PreparedStatement stmt)
              throws PlatformException

Try Oracle update batching and call executeUpdate or revert to JDBC update batching.

Specified by:

addBatch in interface Platform

Overrides:

addBatch in class PlatformDefaultImpl

Parameters:

stmt - the statement beeing added to the batch

Throws:

PlatformException - upon JDBC failure

executeBatch

public int[] executeBatch(java.sql.PreparedStatement stmt)
                   throws PlatformException

Try Oracle update batching and call sendBatch or revert to JDBC update batching.

Specified by:

executeBatch in interface Platform

Overrides:

executeBatch in class PlatformDefaultImpl

Parameters:

stmt - the batched prepared statement about to be executed

Returns:

always null if Oracle update batching is used, since it is impossible to dissolve total row count into distinct statement counts. If JDBC update batching is used, an int array is returned containing number of updated rows for each batched statement.

Throws:

PlatformException - upon JDBC failure

setObjectForStatement

public void setObjectForStatement(java.sql.PreparedStatement ps,
                                  int index,
                                  java.lang.Object value,
                                  int sqlType)
                           throws java.sql.SQLException

Description copied from class: PlatformOracleImpl

For objects beyond 4k, weird things happen in Oracle if you try to use "setBytes", so for all cases it's better to use setBinaryStream. Oracle also requires a change in the resultset type of the prepared statement. MBAIRD NOTE: BLOBS may not work with Oracle database/thin driver versions prior to 8.1.6.

Specified by:

setObjectForStatement in interface Platform

Overrides:

setObjectForStatement in class PlatformOracleImpl

Throws:

java.sql.SQLException

See Also:

Platform.setObjectForStatement(java.sql.PreparedStatement, int, java.lang.Object, int)

getJoinSyntaxType

public byte getJoinSyntaxType()

Get join syntax type for this RDBMS.

Specified by:

getJoinSyntaxType in interface Platform

Overrides:

getJoinSyntaxType in class PlatformOracleImpl

Returns:

SQL92_NOPAREN_JOIN_SYNTAX