org.quartz.impl.jdbcjobstore

Class DBSemaphore

java.lang.Object

org.quartz.impl.jdbcjobstore.DBSemaphore

All Implemented Interfaces:

Constants, Semaphore, StdJDBCConstants, TablePrefixAware

Direct Known Subclasses:

StdRowLockSemaphore, UpdateLockRowSemaphore

public abstract class DBSemaphore
extends java.lang.Object
implements Semaphore, Constants, StdJDBCConstants, TablePrefixAware

Base class for database based lock handlers for providing thread/resource locking in order to protect resources from being altered by multiple threads at the same time.

Field Summary

Fields inherited from interface org.quartz.impl.jdbcjobstore.StdJDBCConstants

COUNT_MISFIRED_TRIGGERS_IN_STATES, DELETE_BLOB_TRIGGER, DELETE_CALENDAR, DELETE_CRON_TRIGGER, DELETE_FIRED_TRIGGER, DELETE_FIRED_TRIGGERS, DELETE_INSTANCES_FIRED_TRIGGERS, DELETE_JOB_DETAIL, DELETE_JOB_LISTENERS, DELETE_NO_RECOVERY_FIRED_TRIGGERS, DELETE_PAUSED_TRIGGER_GROUP, DELETE_PAUSED_TRIGGER_GROUPS, DELETE_SCHEDULER_STATE, DELETE_SIMPLE_TRIGGER, DELETE_TRIGGER, DELETE_TRIGGER_LISTENERS, DELETE_VOLATILE_FIRED_TRIGGERS, INSERT_BLOB_TRIGGER, INSERT_CALENDAR, INSERT_CRON_TRIGGER, INSERT_FIRED_TRIGGER, INSERT_JOB_DETAIL, INSERT_JOB_LISTENER, INSERT_PAUSED_TRIGGER_GROUP, INSERT_SCHEDULER_STATE, INSERT_SIMPLE_TRIGGER, INSERT_TRIGGER, INSERT_TRIGGER_LISTENER, SELECT_BLOB_TRIGGER, SELECT_CALENDAR, SELECT_CALENDAR_EXISTENCE, SELECT_CALENDARS, SELECT_CRON_TRIGGER, SELECT_FIRED_TRIGGER, SELECT_FIRED_TRIGGER_GROUP, SELECT_FIRED_TRIGGER_INSTANCE_NAMES, SELECT_FIRED_TRIGGERS, SELECT_FIRED_TRIGGERS_OF_JOB, SELECT_FIRED_TRIGGERS_OF_JOB_GROUP, SELECT_INSTANCES_FIRED_TRIGGERS, SELECT_INSTANCES_RECOVERABLE_FIRED_TRIGGERS, SELECT_JOB_DETAIL, SELECT_JOB_EXECUTION_COUNT, SELECT_JOB_EXISTENCE, SELECT_JOB_FOR_TRIGGER, SELECT_JOB_GROUPS, SELECT_JOB_LISTENERS, SELECT_JOB_STATEFUL, SELECT_JOBS_IN_GROUP, SELECT_MISFIRED_TRIGGERS, SELECT_MISFIRED_TRIGGERS_IN_GROUP_IN_STATE, SELECT_MISFIRED_TRIGGERS_IN_STATE, SELECT_MISFIRED_TRIGGERS_IN_STATES, SELECT_NEXT_FIRE_TIME, SELECT_NEXT_TRIGGER_TO_ACQUIRE, SELECT_NUM_CALENDARS, SELECT_NUM_JOBS, SELECT_NUM_TRIGGERS, SELECT_NUM_TRIGGERS_FOR_JOB, SELECT_NUM_TRIGGERS_IN_GROUP, SELECT_PAUSED_TRIGGER_GROUP, SELECT_PAUSED_TRIGGER_GROUPS, SELECT_REFERENCED_CALENDAR, SELECT_SCHEDULER_STATE, SELECT_SCHEDULER_STATES, SELECT_SIMPLE_TRIGGER, SELECT_STATEFUL_JOBS_OF_TRIGGER_GROUP, SELECT_TRIGGER, SELECT_TRIGGER_DATA, SELECT_TRIGGER_EXISTENCE, SELECT_TRIGGER_FOR_FIRE_TIME, SELECT_TRIGGER_GROUPS, SELECT_TRIGGER_LISTENERS, SELECT_TRIGGER_STATE, SELECT_TRIGGER_STATUS, SELECT_TRIGGERS_FOR_CALENDAR, SELECT_TRIGGERS_FOR_JOB, SELECT_TRIGGERS_IN_GROUP, SELECT_TRIGGERS_IN_STATE, SELECT_VOLATILE_JOBS, SELECT_VOLATILE_TRIGGERS, TABLE_PREFIX_SUBST, UPDATE_BLOB_TRIGGER, UPDATE_CALENDAR, UPDATE_CRON_TRIGGER, UPDATE_INSTANCES_FIRED_TRIGGER_STATE, UPDATE_JOB_DATA, UPDATE_JOB_DETAIL, UPDATE_JOB_TRIGGER_STATES, UPDATE_JOB_TRIGGER_STATES_FROM_OTHER_STATE, UPDATE_SCHEDULER_STATE, UPDATE_SIMPLE_TRIGGER, UPDATE_TRIGGER, UPDATE_TRIGGER_GROUP_STATE, UPDATE_TRIGGER_GROUP_STATE_FROM_STATE, UPDATE_TRIGGER_GROUP_STATE_FROM_STATES, UPDATE_TRIGGER_SKIP_DATA, UPDATE_TRIGGER_STATE, UPDATE_TRIGGER_STATE_FROM_OTHER_STATES_BEFORE_TIME, UPDATE_TRIGGER_STATE_FROM_STATE, UPDATE_TRIGGER_STATE_FROM_STATES, UPDATE_TRIGGER_STATES_FROM_OTHER_STATES

Fields inherited from interface org.quartz.impl.jdbcjobstore.Constants

ALIAS_COL_NEXT_FIRE_TIME, ALL_GROUPS_PAUSED, COL_BLOB, COL_CALENDAR, COL_CALENDAR_NAME, COL_CHECKIN_INTERVAL, COL_CRON_EXPRESSION, COL_DESCRIPTION, COL_END_TIME, COL_ENTRY_ID, COL_ENTRY_STATE, COL_FIRED_TIME, COL_INSTANCE_NAME, COL_IS_DURABLE, COL_IS_STATEFUL, COL_IS_VOLATILE, COL_JOB_CLASS, COL_JOB_DATAMAP, COL_JOB_GROUP, COL_JOB_LISTENER, COL_JOB_NAME, COL_LAST_CHECKIN_TIME, COL_LOCK_NAME, COL_MISFIRE_INSTRUCTION, COL_NEXT_FIRE_TIME, COL_PREV_FIRE_TIME, COL_PRIORITY, COL_REPEAT_COUNT, COL_REPEAT_INTERVAL, COL_REQUESTS_RECOVERY, COL_START_TIME, COL_TIME_ZONE_ID, COL_TIMES_TRIGGERED, COL_TRIGGER_GROUP, COL_TRIGGER_LISTENER, COL_TRIGGER_NAME, COL_TRIGGER_STATE, COL_TRIGGER_TYPE, DEFAULT_TABLE_PREFIX, STATE_ACQUIRED, STATE_BLOCKED, STATE_COMPLETE, STATE_DELETED, STATE_ERROR, STATE_EXECUTING, STATE_MISFIRED, STATE_PAUSED, STATE_PAUSED_BLOCKED, STATE_WAITING, TABLE_BLOB_TRIGGERS, TABLE_CALENDARS, TABLE_CRON_TRIGGERS, TABLE_FIRED_TRIGGERS, TABLE_JOB_DETAILS, TABLE_JOB_LISTENERS, TABLE_LOCKS, TABLE_PAUSED_TRIGGERS, TABLE_SCHEDULER_STATE, TABLE_SIMPLE_TRIGGERS, TABLE_TRIGGER_LISTENERS, TABLE_TRIGGERS, TTYPE_BLOB, TTYPE_CRON, TTYPE_SIMPLE

Constructor Summary

Constructors

Constructor and Description
DBSemaphore(java.lang.String tablePrefix, java.lang.String sql, java.lang.String defaultSQL)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	isLockOwner(java.sql.Connection conn, java.lang.String lockName) Determine whether the calling thread owns a lock on the identified resource.
boolean	obtainLock(java.sql.Connection conn, java.lang.String lockName) Grants a lock on the identified resource to the calling thread (blocking until it is available).
void	releaseLock(java.sql.Connection conn, java.lang.String lockName) Release the lock on the identified resource if it is held by the calling thread.
boolean	requiresConnection() This Semaphore implementation does use the database.
void	setTablePrefix(java.lang.String tablePrefix)

Methods inherited from class java.lang.Object

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

Constructor Detail

DBSemaphore

public DBSemaphore(java.lang.String tablePrefix,
           java.lang.String sql,
           java.lang.String defaultSQL)

Method Detail

obtainLock

public boolean obtainLock(java.sql.Connection conn,
                 java.lang.String lockName)
                   throws LockException

Grants a lock on the identified resource to the calling thread (blocking until it is available).

Specified by:

obtainLock in interface Semaphore

Parameters:

conn - Database connection used to establish lock. Can be null if Semaphore.requiresConnection() returns false.

Returns:

true if the lock was obtained.

Throws:

LockException

releaseLock

public void releaseLock(java.sql.Connection conn,
               java.lang.String lockName)

Release the lock on the identified resource if it is held by the calling thread.

Specified by:

releaseLock in interface Semaphore

Parameters:

conn - Database connection used to establish lock. Can be null if Semaphore.requiresConnection() returns false.

isLockOwner

public boolean isLockOwner(java.sql.Connection conn,
                  java.lang.String lockName)

Determine whether the calling thread owns a lock on the identified resource.

Specified by:

isLockOwner in interface Semaphore

Parameters:

conn - Database connection used to establish lock. Can be null if Semaphore.requiresConnection() returns false.

requiresConnection

public boolean requiresConnection()

This Semaphore implementation does use the database.

Specified by:

requiresConnection in interface Semaphore

See Also:

Semaphore.isLockOwner(Connection, String), Semaphore.obtainLock(Connection, String), Semaphore.releaseLock(Connection, String)

setTablePrefix

public void setTablePrefix(java.lang.String tablePrefix)

Specified by:

setTablePrefix in interface TablePrefixAware