Class LogicalStatementEntity

java.lang.Object

org.apache.derby.client.am.LogicalStatementEntity

All Implemented Interfaces:

AutoCloseable, Statement, Wrapper

Direct Known Subclasses:

LogicalPreparedStatement

abstract class LogicalStatementEntity
extends Object
implements Statement

Common class interacting with the JDBC statement cache for logical prepared statements and logical callable statements.

Note that getPhysPs() and getPhysCs() takes care of checking if the logical statement has been closed. The physical statement will take care of validating itself.

Beside from the above, special treatment of logical entities happens on close. This is the point where cache interaction takes place, and also where the appropriate methods are called on the physical statement to perform the necessary clean up for later reuse.

A note regarding the thread safety of this class, is that access to physicalPs and physicalCs is guarded by the instance of this class, but it is assumed that operation on/within the physical statement is synchronized in the physical statement itself .

Field Summary

Fields

Modifier and Type	Field	Description
private final JDBCStatementCache	cache	Cache for physical statements.
private final boolean	hasCallableStmt	Tells if we're holding a callable statement or not.
private StatementCacheInteractor	owner	The owner of this logical entity.
private CallableStatement	physicalCs	Associated physical callable statement, if any.
private PreparedStatement	physicalPs	Associated physical prepared statement.
private final StatementKey	stmtKey	The key for the associated statement.

Fields inherited from interface Statement

CLOSE_ALL_RESULTS, CLOSE_CURRENT_RESULT, EXECUTE_FAILED, KEEP_CURRENT_RESULT, NO_GENERATED_KEYS, RETURN_GENERATED_KEYS, SUCCESS_NO_INFO

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	LogicalStatementEntity(PreparedStatement physicalPs, StatementKey stmtKey, StatementCacheInteractor cacheInteractor)	Create a logical entity for a PreparedStatement.

Method Summary

Modifier and Type	Method	Description
void	close()	Close the logical statement.
void	closeOnCompletion()	/////////////////////////////////////////////////////////////////
long[]	executeLargeBatch()	/////////////////////////////////////////////////////////////////
long	executeLargeUpdate(String sql)
long	executeLargeUpdate(String sql, int autoGeneratedKeys)
long	executeLargeUpdate(String sql, int[] columnIndexes)
long	executeLargeUpdate(String sql, String[] columnNames)
long	getLargeMaxRows()
long	getLargeUpdateCount()
(package private) CallableStatement	getPhysCs()	Returns the associated physical callable statement.
(package private) PreparedStatement	getPhysPs()	Returns the associated physical prepared statement.
private Statement	getPhysStmt()	Returns the associated physical statement.
boolean	isCloseOnCompletion()
(package private) boolean	isLogicalEntityClosed()	Tells if the logical entity is closed.
boolean	isWrapperFor(Class<?> iface)	Check whether this instance wraps an object that implements the interface specified by iface.
void	setLargeMaxRows(long maxRows)
<T> T	unwrap(Class<T> iface)	Returns an instance of the specified interface if this instance is a wrapper for the interface.

Methods inherited from class Object

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

Methods inherited from interface Statement

addBatch, cancel, clearBatch, clearWarnings, enquoteIdentifier, enquoteLiteral, enquoteNCharLiteral, execute, execute, execute, execute, executeBatch, executeQuery, executeUpdate, executeUpdate, executeUpdate, executeUpdate, getConnection, getFetchDirection, getFetchSize, getGeneratedKeys, getMaxFieldSize, getMaxRows, getMoreResults, getMoreResults, getQueryTimeout, getResultSet, getResultSetConcurrency, getResultSetHoldability, getResultSetType, getUpdateCount, getWarnings, isClosed, isPoolable, isSimpleIdentifier, setCursorName, setEscapeProcessing, setFetchDirection, setFetchSize, setMaxFieldSize, setMaxRows, setPoolable, setQueryTimeout

Field Details

hasCallableStmt

private final boolean hasCallableStmt

Tells if we're holding a callable statement or not.

Used for sanity checking.

physicalPs

private PreparedStatement physicalPs

Associated physical prepared statement.

If this is null, the logical entity is closed.

physicalCs

private CallableStatement physicalCs

Associated physical callable statement, if any.

This is a convenience reference, to avoid having to cast on every invocation of getPhysCs() if the logical entity represents a callable statement.

owner

private StatementCacheInteractor owner

The owner of this logical entity.

stmtKey

private final StatementKey stmtKey

The key for the associated statement.

cache

private final JDBCStatementCache cache

Cache for physical statements.

Constructor Details

LogicalStatementEntity

protected LogicalStatementEntity(PreparedStatement physicalPs,
 StatementKey stmtKey,
 StatementCacheInteractor cacheInteractor)

Create a logical entity for a PreparedStatement.

Parameters:

physicalPs - a physical PreparedStatement

stmtKey - cache key for the physical statement

cacheInteractor - creating statement cache interactor

Throws:

IllegalArgumentException - if cache is null

Method Details

getPhysPs

PreparedStatement getPhysPs()
                     throws SQLException

Returns the associated physical prepared statement.

Returns:

A prepared statement.

Throws:

SQLException - if the logical statement has been closed

getPhysCs

CallableStatement getPhysCs()
                     throws SQLException

Returns the associated physical callable statement.

Returns:

A callable statement.

Throws:

SQLException - if the logical statement has been closed

getPhysStmt

private Statement getPhysStmt()
                       throws SQLException

Returns the associated physical statement.

Returns:

A statement.

Throws:

SQLException - if the logical statement has been closed

close

public void close()
           throws SQLException

Close the logical statement.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Statement

Throws:

SQLException - if closing the statement fails

isLogicalEntityClosed

boolean isLogicalEntityClosed()

Tells if the logical entity is closed.

If this method is used to avoid the possibility of raising an exception because the logical statement has been closed and then invoke a method on the physical statement, one must synchronize on this instance in the calling code.

Returns:

true if closed, false if open.

isWrapperFor

public boolean isWrapperFor(Class<?> iface)
                     throws SQLException

Check whether this instance wraps an object that implements the interface specified by iface.

Specified by:

isWrapperFor in interface Wrapper

Parameters:

iface - a class defining an interface

Returns:

true if this instance implements iface, or false otherwise

Throws:

SQLException - if an error occurs while determining if this instance implements iface

unwrap

public <T> T unwrap(Class<T> iface)
             throws SQLException

Returns an instance of the specified interface if this instance is a wrapper for the interface.

Specified by:

unwrap in interface Wrapper

Parameters:

iface - a class defining an interface

Returns:

an object that implements the interface

Throws:

SQLException - if no object is found that implements the interface

closeOnCompletion

public void closeOnCompletion()
                       throws SQLException

/////////////////////////////////////////////////////////////////

Specified by:

closeOnCompletion in interface Statement

Throws:

SQLException

isCloseOnCompletion

public boolean isCloseOnCompletion()
                            throws SQLException

Specified by:

isCloseOnCompletion in interface Statement

Throws:

SQLException

executeLargeBatch

public long[] executeLargeBatch()
                         throws SQLException

/////////////////////////////////////////////////////////////////

Specified by:

executeLargeBatch in interface Statement

Throws:

SQLException

executeLargeUpdate

public long executeLargeUpdate(String sql)
                        throws SQLException

Specified by:

executeLargeUpdate in interface Statement

Throws:

SQLException

executeLargeUpdate

public long executeLargeUpdate(String sql,
 int autoGeneratedKeys)
                        throws SQLException

Specified by:

executeLargeUpdate in interface Statement

Throws:

SQLException

executeLargeUpdate

public long executeLargeUpdate(String sql,
 int[] columnIndexes)
                        throws SQLException

Specified by:

executeLargeUpdate in interface Statement

Throws:

SQLException

executeLargeUpdate

public long executeLargeUpdate(String sql,
 String[] columnNames)
                        throws SQLException

Specified by:

executeLargeUpdate in interface Statement

Throws:

SQLException

getLargeUpdateCount

public long getLargeUpdateCount()
                         throws SQLException

Specified by:

getLargeUpdateCount in interface Statement

Throws:

SQLException

getLargeMaxRows

public long getLargeMaxRows()
                     throws SQLException

Specified by:

getLargeMaxRows in interface Statement

Throws:

SQLException

setLargeMaxRows

public void setLargeMaxRows(long maxRows)
                     throws SQLException

Specified by:

setLargeMaxRows in interface Statement

Throws:

SQLException