Package net.solarnetwork.dao.jdbc

Class JdbcBulkLoadingContextSupport<T>

java.lang.Object

net.solarnetwork.dao.jdbc.JdbcBulkLoadingContextSupport<T>

Type Parameters:

T - the entity type

All Implemented Interfaces:

AutoCloseable, BulkLoadingDao.LoadingContext<T>, org.springframework.jdbc.core.SqlProvider

public abstract class JdbcBulkLoadingContextSupport<T>
extends Object
implements BulkLoadingDao.LoadingContext<T>, org.springframework.jdbc.core.SqlProvider

Base implementation of BulkLoadingDao.LoadingContext for JDBC stored procedure based implementations.

This class handles the low-level transaction semantics for the load operation, and relies on extending classes to implement the doLoad(Object, PreparedStatement, long) method to save each entity into the backend database.

Version:

1.0

Author:

matt

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_BATCH_SIZE	The default batch size.
protected final org.slf4j.Logger	log	A class-level logger.

Constructor Summary

Constructors

Constructor	Description
JdbcBulkLoadingContextSupport(org.springframework.transaction.PlatformTransactionManager txManager, DataSource dataSource, String sql, BulkLoadingDao.LoadingOptions options, BulkLoadingDao.LoadingExceptionHandler<T> exceptionHandler)	Constructor.

Method Summary

Modifier and Type	Method	Description
void	close()	Close any temporary resources.
void	commit()	Commit the current transaction.
void	createCheckpoint()	Create a checkpoint that can be rolled back to.
protected PreparedStatement	createJdbcStatement(Connection con)	Create the JDBC statement to use.
protected abstract boolean	doLoad(T entity, PreparedStatement stmt, long index)	Load a single entity.
long	getCommittedCount()	Get the count of entities committed thus far using this context.
protected Connection	getConnection()	Get the JDBC connection.
DataSource	getDataSource()	Get the JDBC data source.
BulkLoadingDao.LoadingExceptionHandler<T>	getExceptionHandler()	Get the exception handler.
T	getLastLoadedEntity()	Get the entity that was last passed to the BulkLoadingDao.LoadingContext.load(Object) method.
long	getLoadedCount()	Get the count of entities loaded thus far using this context.
BulkLoadingDao.LoadingOptions	getOptions()	Get the loading options used to create the context.
String	getSql()	Get the JDBC statement to use for bulk loading.
org.springframework.transaction.PlatformTransactionManager	getTransactionManager()	Get the transaction manager.
final void	load(T entity)	Load an entity.
void	rollback()	Discard the entities loaded within the current transaction.

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_BATCH_SIZE

public static final int DEFAULT_BATCH_SIZE

The default batch size.

See Also:

• Constant Field Values

log

protected final org.slf4j.Logger log

A class-level logger.

Constructor Details

JdbcBulkLoadingContextSupport

public JdbcBulkLoadingContextSupport(org.springframework.transaction.PlatformTransactionManager txManager,
 DataSource dataSource,
 String sql,
 BulkLoadingDao.LoadingOptions options,
 BulkLoadingDao.LoadingExceptionHandler<T> exceptionHandler)

Constructor.

Parameters:

txManager - the transaction manager

dataSource - the data source

sql - the SQL statement (or JDBC SQL call) to execute

options - the options

exceptionHandler - an exception handler

Method Details

getOptions

public BulkLoadingDao.LoadingOptions getOptions()

Description copied from interface: BulkLoadingDao.LoadingContext

Get the loading options used to create the context.

Specified by:

getOptions in interface BulkLoadingDao.LoadingContext<T>

Returns:

the loading options

getLoadedCount

public long getLoadedCount()

Description copied from interface: BulkLoadingDao.LoadingContext

Get the count of entities loaded thus far using this context.

If BulkLoadingDao.LoadingContext.rollback() is called, this value will reset back to the count of currently committed entities.

Specified by:

getLoadedCount in interface BulkLoadingDao.LoadingContext<T>

Returns:

the loaded count

getCommittedCount

public long getCommittedCount()

Description copied from interface: BulkLoadingDao.LoadingContext

Get the count of entities committed thus far using this context.

How this value increments depends on the BulkLoadingDao.LoadingTransactionMode defined in the options that were used to create this context:

BulkLoadingDao.LoadingTransactionMode.NoTransaction

This count will match BulkLoadingDao.LoadingContext.getLoadedCount() and increment as each entity is loaded.

BulkLoadingDao.LoadingTransactionMode.BatchTransactions

This count will increment only after each batch of loaded entity have been committed, and thus can lag behind BulkLoadingDao.LoadingContext.getLoadedCount().

BulkLoadingDao.LoadingTransactionMode.TransactionCheckpoints

This count will only increment after calls to BulkLoadingDao.LoadingContext.createCheckpoint() are made. If BulkLoadingDao.LoadingContext.rollback() is called, this count will reset back to the count at the previous time BulkLoadingDao.LoadingContext.createCheckpoint() was called.

BulkLoadingDao.LoadingTransactionMode.SingleTransaction

This count will remain at 0 until BulkLoadingDao.LoadingContext.commit() is called, at which point it will match BulkLoadingDao.LoadingContext.getLoadedCount().

Specified by:

getCommittedCount in interface BulkLoadingDao.LoadingContext<T>

Returns:

the committed entity count

getConnection

protected Connection getConnection()
                            throws SQLException

Get the JDBC connection.

Returns:

the connection

Throws:

SQLException - if any SQL error occurs

getLastLoadedEntity

public T getLastLoadedEntity()

Description copied from interface: BulkLoadingDao.LoadingContext

Get the entity that was last passed to the BulkLoadingDao.LoadingContext.load(Object) method.

Specified by:

getLastLoadedEntity in interface BulkLoadingDao.LoadingContext<T>

Returns:

the last loaded entity

load

public final void load(T entity)

Description copied from interface: BulkLoadingDao.LoadingContext

Load an entity.

Specified by:

load in interface BulkLoadingDao.LoadingContext<T>

Parameters:

entity - the entity to load

doLoad

protected abstract boolean doLoad(T entity,
 PreparedStatement stmt,
 long index)
                           throws SQLException

Load a single entity.

Extending classes must implement this method to perform the actual saving of the entity to JDBC.

Parameters:

entity - the entity to load

stmt - the statement to use

index - the loading index

Returns:

true if loaded

Throws:

SQLException - if any SQL error occurs

createCheckpoint

public void createCheckpoint()

Description copied from interface: BulkLoadingDao.LoadingContext

Create a checkpoint that can be rolled back to.

The BulkLoadingDao.LoadingTransactionMode.TransactionCheckpoints mode must have been set in the options used to create this context.

Specified by:

createCheckpoint in interface BulkLoadingDao.LoadingContext<T>

commit

public void commit()

Description copied from interface: BulkLoadingDao.LoadingContext

Commit the current transaction.

The nature of the current transaction depends on the transaction mode set in the options used to create this context:

TransactionCheckpoints or SingleTransaction

All entities loaded via BulkLoadingDao.LoadingContext.load(Object) are committed.

BatchTransactions

The entities loaded via BulkLoadingDao.LoadingContext.load(Object) since the last automatic batch commit are committed.

Specified by:

commit in interface BulkLoadingDao.LoadingContext<T>

rollback

public void rollback()

Description copied from interface: BulkLoadingDao.LoadingContext

Discard the entities loaded within the current transaction.

The nature of the current transaction depends on the transaction mode set in the options used to create this context:

SingleTransaction

All entities loaded are discarded.

TransactionCheckpoints

All entities loaded via BulkLoadingDao.LoadingContext.load(Object) since the last call to BulkLoadingDao.LoadingContext.createCheckpoint() are discarded.

BatchTransactions

The entities loaded via BulkLoadingDao.LoadingContext.load(Object) since the last automatic batch commit are discarded.

Specified by:

rollback in interface BulkLoadingDao.LoadingContext<T>

close

public void close()

Description copied from interface: BulkLoadingDao.LoadingContext

Close any temporary resources.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface BulkLoadingDao.LoadingContext<T>

createJdbcStatement

protected PreparedStatement createJdbcStatement(Connection con)
                                         throws SQLException

Create the JDBC statement to use.

This implementation invokes Connection.prepareCall(String), passing getSql(). Extending classes can override to customize this behavior.

Parameters:

con - the JDBC connection

Returns:

the statement

Throws:

SQLException - if any SQL error occurs

getTransactionManager

public org.springframework.transaction.PlatformTransactionManager getTransactionManager()

Get the transaction manager.

Returns:

the manager

getDataSource

public DataSource getDataSource()

Get the JDBC data source.

Returns:

the dataSource

getSql

public String getSql()

Get the JDBC statement to use for bulk loading.

Specified by:

getSql in interface org.springframework.jdbc.core.SqlProvider

getExceptionHandler

public BulkLoadingDao.LoadingExceptionHandler<T> getExceptionHandler()

Get the exception handler.

Returns:

the exceptionHandler