software.amazon.jdbc.plugin.failover

Class FailoverConnectionPlugin

java.lang.Object

software.amazon.jdbc.plugin.AbstractConnectionPlugin

software.amazon.jdbc.plugin.failover.FailoverConnectionPlugin

All Implemented Interfaces:

ConnectionPlugin

public class FailoverConnectionPlugin
extends AbstractConnectionPlugin

This plugin provides cluster-aware failover features. The plugin switches connections upon detecting communication related exceptions and/or cluster topology changes.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.String	closedReason
static AwsWrapperProperty	ENABLE_CLUSTER_AWARE_FAILOVER
protected boolean	enableFailoverSetting
protected boolean	explicitlyAutoCommit
static AwsWrapperProperty	FAILOVER_CLUSTER_TOPOLOGY_REFRESH_RATE_MS
static AwsWrapperProperty	FAILOVER_READER_CONNECT_TIMEOUT_MS
static AwsWrapperProperty	FAILOVER_TIMEOUT_MS
static AwsWrapperProperty	FAILOVER_WRITER_RECONNECT_INTERVAL_MS
protected int	failoverClusterTopologyRefreshRateMsSetting
protected int	failoverReaderConnectTimeoutMsSetting
protected int	failoverTimeoutMsSetting
protected int	failoverWriterReconnectIntervalMsSetting
protected boolean	isClosed
protected java.util.Properties	properties
protected ReaderFailoverHandler	readerFailoverHandler
protected WriterFailoverHandler	writerFailoverHandler

Constructor Summary

Constructors

Constructor and Description
FailoverConnectionPlugin(PluginService pluginService, java.util.Properties properties)

Method Summary

Modifier and Type	Method and Description
java.sql.Connection	connect(java.lang.String driverProtocol, HostSpec hostSpec, java.util.Properties props, boolean isInitialConnection, JdbcCallable<java.sql.Connection,java.sql.SQLException> connectFunc)
protected java.sql.Connection	createConnectionForHost(HostSpec baseHostSpec) Creates a new physical connection for the given HostSpec.
protected <E extends java.lang.Exception> void	dealWithIllegalStateException(java.lang.IllegalStateException e, java.lang.Class<E> exceptionClass)
<T,E extends java.lang.Exception> T	execute(java.lang.Class<T> resultClass, java.lang.Class<E> exceptionClass, java.lang.Object methodInvokeOn, java.lang.String methodName, JdbcCallable<T,E> jdbcMethodFunc, java.lang.Object[] jdbcMethodArgs)
protected void	failover(HostSpec failedHost) Initiates the failover procedure.
protected void	failoverReader(HostSpec failedHostSpec)
protected void	failoverWriter()
java.util.Set<java.lang.String>	getSubscribedMethods()
void	initHostProvider(java.lang.String driverProtocol, java.lang.String initialUrl, java.util.Properties props, HostListProviderService hostListProviderService, JdbcCallable<java.lang.Void,java.sql.SQLException> initHostProviderFunc)
protected void	invalidateCurrentConnection()
boolean	isFailoverEnabled()
OldConnectionSuggestedAction	notifyConnectionChanged(java.util.EnumSet<NodeChangeOptions> changes)
void	notifyNodeListChanged(java.util.Map<java.lang.String,java.util.EnumSet<NodeChangeOptions>> changes)
protected void	pickNewConnection()
protected boolean	shouldExceptionTriggerConnectionSwitch(java.lang.Throwable t)
protected void	transferSessionState(java.sql.Connection from, java.sql.Connection to, boolean readOnly) Transfers basic session state from one connection to another.
protected void	updateTopology(boolean forceUpdate)

Methods inherited from class java.lang.Object

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

Field Detail

properties

protected final java.util.Properties properties

enableFailoverSetting

protected boolean enableFailoverSetting

failoverTimeoutMsSetting

protected int failoverTimeoutMsSetting

failoverClusterTopologyRefreshRateMsSetting

protected int failoverClusterTopologyRefreshRateMsSetting

failoverWriterReconnectIntervalMsSetting

protected int failoverWriterReconnectIntervalMsSetting

failoverReaderConnectTimeoutMsSetting

protected int failoverReaderConnectTimeoutMsSetting

explicitlyAutoCommit

protected boolean explicitlyAutoCommit

isClosed

protected boolean isClosed

closedReason

protected java.lang.String closedReason

writerFailoverHandler

protected WriterFailoverHandler writerFailoverHandler

readerFailoverHandler

protected ReaderFailoverHandler readerFailoverHandler

FAILOVER_CLUSTER_TOPOLOGY_REFRESH_RATE_MS

public static final AwsWrapperProperty FAILOVER_CLUSTER_TOPOLOGY_REFRESH_RATE_MS

FAILOVER_TIMEOUT_MS

public static final AwsWrapperProperty FAILOVER_TIMEOUT_MS

FAILOVER_WRITER_RECONNECT_INTERVAL_MS

public static final AwsWrapperProperty FAILOVER_WRITER_RECONNECT_INTERVAL_MS

FAILOVER_READER_CONNECT_TIMEOUT_MS

public static final AwsWrapperProperty FAILOVER_READER_CONNECT_TIMEOUT_MS

ENABLE_CLUSTER_AWARE_FAILOVER

public static final AwsWrapperProperty ENABLE_CLUSTER_AWARE_FAILOVER

Constructor Detail

FailoverConnectionPlugin

public FailoverConnectionPlugin(PluginService pluginService,
                                java.util.Properties properties)

Method Detail

getSubscribedMethods

public java.util.Set<java.lang.String> getSubscribedMethods()

Specified by:

getSubscribedMethods in interface ConnectionPlugin

Specified by:

getSubscribedMethods in class AbstractConnectionPlugin

execute

public <T,E extends java.lang.Exception> T execute(java.lang.Class<T> resultClass,
                                                   java.lang.Class<E> exceptionClass,
                                                   java.lang.Object methodInvokeOn,
                                                   java.lang.String methodName,
                                                   JdbcCallable<T,E> jdbcMethodFunc,
                                                   java.lang.Object[] jdbcMethodArgs)
                                            throws E extends java.lang.Exception

Specified by:

execute in interface ConnectionPlugin

Overrides:

execute in class AbstractConnectionPlugin

Throws:

E extends java.lang.Exception

initHostProvider

public void initHostProvider(java.lang.String driverProtocol,
                             java.lang.String initialUrl,
                             java.util.Properties props,
                             HostListProviderService hostListProviderService,
                             JdbcCallable<java.lang.Void,java.sql.SQLException> initHostProviderFunc)
                      throws java.sql.SQLException

Specified by:

initHostProvider in interface ConnectionPlugin

Overrides:

initHostProvider in class AbstractConnectionPlugin

Throws:

java.sql.SQLException

notifyConnectionChanged

public OldConnectionSuggestedAction notifyConnectionChanged(java.util.EnumSet<NodeChangeOptions> changes)

Specified by:

notifyConnectionChanged in interface ConnectionPlugin

Overrides:

notifyConnectionChanged in class AbstractConnectionPlugin

notifyNodeListChanged

public void notifyNodeListChanged(java.util.Map<java.lang.String,java.util.EnumSet<NodeChangeOptions>> changes)

Specified by:

notifyNodeListChanged in interface ConnectionPlugin

Overrides:

notifyNodeListChanged in class AbstractConnectionPlugin

isFailoverEnabled

public boolean isFailoverEnabled()

updateTopology

protected void updateTopology(boolean forceUpdate)
                       throws java.sql.SQLException

Throws:

java.sql.SQLException

transferSessionState

protected void transferSessionState(java.sql.Connection from,
                                    java.sql.Connection to,
                                    boolean readOnly)
                             throws java.sql.SQLException

Transfers basic session state from one connection to another.

Parameters:

from - The connection to transfer state from

to - The connection to transfer state to

readOnly - The desired read-only state

Throws:

java.sql.SQLException - if a database access error occurs, this method is called on a closed connection or this method is called during a transaction

createConnectionForHost

protected java.sql.Connection createConnectionForHost(HostSpec baseHostSpec)
                                               throws java.sql.SQLException

Creates a new physical connection for the given HostSpec.

Parameters:

baseHostSpec - The host info instance to base the connection off of.

Returns:

The new Connection instance.

Throws:

java.sql.SQLException - if an error occurs

dealWithIllegalStateException

protected <E extends java.lang.Exception> void dealWithIllegalStateException(java.lang.IllegalStateException e,
                                                                             java.lang.Class<E> exceptionClass)
                                                                      throws E extends java.lang.Exception

Throws:

E extends java.lang.Exception

failover

protected void failover(HostSpec failedHost)
                 throws java.sql.SQLException

Initiates the failover procedure. This process tries to establish a new connection to an instance in the topology.

Parameters:

failedHost - The host with network errors.

Throws:

java.sql.SQLException - if an error occurs

failoverReader

protected void failoverReader(HostSpec failedHostSpec)
                       throws java.sql.SQLException

Throws:

java.sql.SQLException

failoverWriter

protected void failoverWriter()
                       throws java.sql.SQLException

Throws:

java.sql.SQLException

invalidateCurrentConnection

protected void invalidateCurrentConnection()

pickNewConnection

protected void pickNewConnection()
                          throws java.sql.SQLException

Throws:

java.sql.SQLException

shouldExceptionTriggerConnectionSwitch

protected boolean shouldExceptionTriggerConnectionSwitch(java.lang.Throwable t)

connect

public java.sql.Connection connect(java.lang.String driverProtocol,
                                   HostSpec hostSpec,
                                   java.util.Properties props,
                                   boolean isInitialConnection,
                                   JdbcCallable<java.sql.Connection,java.sql.SQLException> connectFunc)
                            throws java.sql.SQLException

Specified by:

connect in interface ConnectionPlugin

Overrides:

connect in class AbstractConnectionPlugin

Throws:

java.sql.SQLException