Package org.hibernate.dialect.lock

Class PessimisticReadSelectLockingStrategy

java.lang.Object

org.hibernate.dialect.lock.AbstractSelectLockingStrategy

org.hibernate.dialect.lock.PessimisticReadSelectLockingStrategy

All Implemented Interfaces:

LockingStrategy

public class PessimisticReadSelectLockingStrategy
extends AbstractSelectLockingStrategy

A pessimistic locking strategy where the locks are obtained through select statements.

For non-read locks, this is achieved through the Dialect's specific SELECT ... FOR UPDATE syntax. This strategy is valid for LockMode.PESSIMISTIC_READ This class is a clone of SelectLockingStrategy.

Since:

3.5

See Also:

• Dialect.getForUpdateString(org.hibernate.LockMode)
• Dialect.appendLockHint(org.hibernate.LockMode, String)

Constructor Summary

Constructors

Constructor	Description
PessimisticReadSelectLockingStrategy(Lockable lockable, LockMode lockMode)	Construct a locking strategy based on SQL SELECT statements.

Method Summary

Modifier and Type	Method	Description
protected String	generateLockString(int lockTimeout)
void	lock(Serializable id, Object version, Object object, int timeout, SessionImplementor session)	Acquire an appropriate type of lock on the underlying data that will endure until the end of the current transaction.

Methods inherited from class org.hibernate.dialect.lock.AbstractSelectLockingStrategy

determineSql, getLockable, getLockMode, getNoWaitSql

Methods inherited from class java.lang.Object

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

Constructor Details

PessimisticReadSelectLockingStrategy

public PessimisticReadSelectLockingStrategy(Lockable lockable,
 LockMode lockMode)

Construct a locking strategy based on SQL SELECT statements.

Parameters:

lockable - The metadata for the entity to be locked.

lockMode - Indicates the type of lock to be acquired.

Method Details

lock

public void lock(Serializable id,
 Object version,
 Object object,
 int timeout,
 SessionImplementor session)
          throws StaleObjectStateException,
JDBCException

Description copied from interface: LockingStrategy

Acquire an appropriate type of lock on the underlying data that will endure until the end of the current transaction.

Parameters:

id - The id of the row to be locked

version - The current version (or null if not versioned)

object - The object logically being locked (currently not used)

timeout - timeout in milliseconds, 0 = no wait, -1 = wait indefinitely

session - The session from which the lock request originated

Throws:

StaleObjectStateException - Indicates an optimistic lock failure as part of acquiring the requested database lock.

JDBCException - Indicates errors from the JDBC driver.

See Also:

• LockingStrategy.lock(java.io.Serializable, java.lang.Object, java.lang.Object, int, org.hibernate.engine.SessionImplementor)

generateLockString

protected String generateLockString(int lockTimeout)

Specified by:

generateLockString in class AbstractSelectLockingStrategy