org.objectweb.cjdbc.controller.loadbalancer.raidb2
Class RAIDb2ec

java.lang.Object
  javax.management.StandardMBean
      org.objectweb.cjdbc.controller.jmx.AbstractStandardMBean
          org.objectweb.cjdbc.controller.loadbalancer.AbstractLoadBalancer
              org.objectweb.cjdbc.controller.loadbalancer.raidb2.RAIDb2
                  org.objectweb.cjdbc.controller.loadbalancer.raidb2.RAIDb2ec

All Implemented Interfaces:

AbstractLoadBalancerMBean, javax.management.DynamicMBean, javax.management.NotificationBroadcaster, javax.management.NotificationEmitter, XmlComponent

Direct Known Subclasses:

RAIDb2ec_RR, RAIDb2ec_WRR

public abstract class RAIDb2ec

extends RAIDb2

RAIDb-2ec load balancer.

This class is an abstract call because the read requests coming from the request manager are NOT treated here but in the subclasses. This class deals with backend enable/disable for backendReadThreads creation/termination.

Version:

1.0

Author:

Emmanuel Cecchet

Nested Class Summary

Nested classes inherited from class javax.management.StandardMBean

Field Summary

protected java.util.ArrayList	backendReadThreads
protected ErrorCheckingPolicy	errorCheckingPolicy
protected static Trace	logger
protected int	nbOfConcurrentReads

Fields inherited from class org.objectweb.cjdbc.controller.loadbalancer.raidb2.RAIDb2

backendBlockingThreads, backendBlockingThreadsRWLock, backendNonBlockingThreads, backendNonBlockingThreadsRWLock, createTablePolicy, waitForCompletionPolicy

Fields inherited from class org.objectweb.cjdbc.controller.loadbalancer.AbstractLoadBalancer

macroHandler, parsingGranularity, raidbLevel, totalOrderQueue, vdb

Fields inherited from class org.objectweb.cjdbc.controller.jmx.AbstractStandardMBean

Fields inherited from class javax.management.StandardMBean

Fields inherited from interface org.objectweb.cjdbc.common.xml.XmlComponent

DOCTYPE_CONTROLLER, DOCTYPE_DB, XML_VERSION

Constructor Summary

RAIDb2ec(VirtualDatabase vdb, WaitForCompletionPolicy waitForCompletionPolicy, CreateTablePolicy createTablePolicy, ErrorCheckingPolicy errorCheckingPolicy, int nbOfConcurrentReads)
Creates a new RAIDb-1 Round Robin request load balancer.

Method Summary

void	disableBackend(DatabaseBackend db) Disables a backend that was previously enabled.
void	enableBackend(DatabaseBackend db, boolean writeEnabled) Enables a backend that was previously disabled.
java.lang.String	getXmlImpl() Get information about the Request Load Balancer in xml

Methods inherited from class org.objectweb.cjdbc.controller.loadbalancer.raidb2.RAIDb2

begin, commit, execReadRequest, execReadStoredProcedure, executeRequestOnBackend, executeStoredProcedureOnBackend, execWriteRequest, execWriteRequestWithKeys, execWriteStoredProcedure, getNumberOfEnabledBackends, getRaidb2Xml, releaseSavepoint, rollback, rollback, setSavepoint, waitForAllWritesToComplete, waitForAllWritesToComplete, waitForAllWritesToComplete

Methods inherited from class org.objectweb.cjdbc.controller.loadbalancer.AbstractLoadBalancer

execReadOnlyReadStoredProcedure, executeReadStoredProcedureOnBackend, executeSelectRequestOnBackend, executeUpdateRequestOnBackend, executeUpdateRequestOnBackendWithKeys, executeWriteStoredProcedureOnBackend, getAssociatedString, getConnectionAndBeginTransaction, getInformation, getParsingGranularity, getRAIDbLevel, getXml, handleMacros, removeHeadFromAndNotifyTotalOrderQueue, setMacroHandler, setParsingGranularity, setRAIDbLevel, setWeight, waitForTotalOrder

Methods inherited from class org.objectweb.cjdbc.controller.jmx.AbstractStandardMBean

addNotificationListener, getDescription, getDescription, getDescription, getDescription, getDescription, getDescription, getNotificationInfo, getParameterName, getParameterName, removeNotificationListener, removeNotificationListener, sendNotification

Methods inherited from class javax.management.StandardMBean

cacheMBeanInfo, getAttribute, getAttributes, getCachedMBeanInfo, getClassName, getConstructors, getDescription, getImpact, getImplementation, getImplementationClass, getMBeanInfo, getMBeanInterface, invoke, setAttribute, setAttributes, setImplementation

Methods inherited from class java.lang.Object

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

Field Detail

backendReadThreads

protected java.util.ArrayList backendReadThreads

nbOfConcurrentReads

protected int nbOfConcurrentReads

errorCheckingPolicy

protected ErrorCheckingPolicy errorCheckingPolicy

logger

protected static Trace logger

Constructor Detail

RAIDb2ec

public RAIDb2ec(VirtualDatabase vdb,
                WaitForCompletionPolicy waitForCompletionPolicy,
                CreateTablePolicy createTablePolicy,
                ErrorCheckingPolicy errorCheckingPolicy,
                int nbOfConcurrentReads)
         throws java.lang.Exception

Creates a new RAIDb-1 Round Robin request load balancer. A new backend worker thread is created for each backend.

Parameters:

vdb - the virtual database this load balancer belongs to.

waitForCompletionPolicy - how many backends must complete before returning the result?

createTablePolicy - the policy defining how 'create table' statements should be handled

errorCheckingPolicy - policy to apply for error checking.

nbOfConcurrentReads - number of concurrent reads allowed

Throws:

java.lang.Exception - if an error occurs

Method Detail

enableBackend

public void enableBackend(DatabaseBackend db,
                          boolean writeEnabled)
                   throws java.sql.SQLException

Enables a backend that was previously disabled.

Ask the corresponding connection manager to initialize the connections if needed.

No sanity checks are performed by this function.

Overrides:

enableBackend in class RAIDb2

Parameters:

db - the database backend to enable

writeEnabled - True if the backend must be enabled for writes

Throws:

java.sql.SQLException - if an error occurs

disableBackend

public void disableBackend(DatabaseBackend db)
                    throws java.sql.SQLException

Disables a backend that was previously enabled.

Ask the corresponding connection manager to finalize the connections if needed.

No sanity checks are performed by this function.

Overrides:

disableBackend in class RAIDb2

Parameters:

db - the database backend to disable

Throws:

java.sql.SQLException - if an error occurs

getXmlImpl

public java.lang.String getXmlImpl()

Description copied from class: AbstractLoadBalancer

Get information about the Request Load Balancer in xml

Overrides:

getXmlImpl in class RAIDb2

See Also:

AbstractLoadBalancer.getXmlImpl()