com.mysql.cj.jdbc.ha.ca

Class ClusterAwareConnectionProxy

java.lang.Object

com.mysql.cj.jdbc.ha.MultiHostConnectionProxy

com.mysql.cj.jdbc.ha.ca.ClusterAwareConnectionProxy

All Implemented Interfaces:

ConnectionLifecycleInterceptorProvider, java.lang.reflect.InvocationHandler

public class ClusterAwareConnectionProxy
extends MultiHostConnectionProxy
implements ConnectionLifecycleInterceptorProvider

A proxy for a dynamic com.mysql.cj.jdbc.JdbcConnection implementation that provides cluster-aware failover features. Connection switching occurs on communications related exceptions and/or cluster topology changes.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.String	clusterIdSetting
protected java.lang.String	clusterInstanceHostPatternSetting
protected int	clusterTopologyRefreshRateMsSetting
protected ConnectionProvider	connectionProvider
protected int	currentHostIndex
protected static int	DEFAULT_CONNECT_TIMEOUT_MS
protected static int	DEFAULT_SOCKET_TIMEOUT_MS
protected boolean	enableFailoverSetting
protected boolean	explicitlyAutoCommit
protected java.lang.Boolean	explicitlyReadOnly
protected int	failoverClusterTopologyRefreshRateMsSetting
protected int	failoverConnectTimeoutMs
protected int	failoverReaderConnectTimeoutMsSetting
protected int	failoverSocketTimeoutMs
protected int	failoverTimeoutMsSetting
protected int	failoverWriterReconnectIntervalMsSetting
protected boolean	gatherPerfMetricsSetting
protected java.util.List<HostInfo>	hosts
protected boolean	inTransaction
protected boolean	isClusterTopologyAvailable
protected boolean	isMultiWriterCluster
protected boolean	isRds
protected boolean	isRdsProxy
protected Log	log The logger we're going to use.
protected java.lang.String	loggerClassNameSetting
protected ClusterAwareMetrics	metrics
protected static int	NO_CONNECTION_INDEX
protected static Log	NULL_LOGGER Null logger shared by all connections at startup.
protected ReaderFailoverHandler	readerFailoverHandler
protected TopologyService	topologyService
protected static int	WRITER_CONNECTION_INDEX
protected WriterFailoverHandler	writerFailoverHandler

Fields inherited from class com.mysql.cj.jdbc.ha.MultiHostConnectionProxy

autoReconnect, closedExplicitly, closedReason, connectionUrl, currentConnection, hostsList, isClosed, lastExceptionDealtWith, thisAsConnection

Constructor Summary

Constructors

Constructor and Description
ClusterAwareConnectionProxy(ConnectionUrl connectionUrl) Instantiates a new AuroraConnectionProxy for the given list of hosts and connection properties.

Method Summary

Modifier and Type	Method and Description
static JdbcConnection	autodetectClusterAndCreateProxyInstance(ConnectionUrl connectionUrl) Checks if connection is associated with Aurora cluster and instantiates a new AuroraConnectionProxy if needed.
protected void	createConnectionAndInitializeTopology(ConnectionUrl connUrl)
protected ConnectionImpl	createConnectionForHost(HostInfo hostInfo) Creates a new physical connection for the given HostInfo.
static JdbcConnection	createProxyInstance(ConnectionUrl connectionUrl) Instantiates a new AuroraConnectionProxy.
protected void	dealWithInvocationException(java.lang.reflect.InvocationTargetException e) Deals with InvocationException from proxied objects.
protected void	doAbort(java.util.concurrent.Executor executor) Aborts current connection using the given executor.
protected void	doAbortInternal() Aborts current connection.
protected void	doClose() Closes current connection.
protected void	failover(int failedHostIdx) Initiates a default failover procedure starting at the given host index.
protected void	failoverReader(int failedHostIdx)
protected void	failoverWriter()
protected JdbcConnection	getConnection()
ConnectionLifecycleInterceptor	getConnectionLifecycleInterceptor()
protected void	initClusterInfo(ConnectionUrl connUrl)
protected void	initLogger()
protected void	initSettings(ConnectionUrl connectionUrl)
protected void	invalidateCurrentConnection() Invalidates the current connection.
java.lang.Object	invoke(java.lang.Object proxy, java.lang.reflect.Method method, java.lang.Object[] args) Proxies method invocation on the java.sql.Connection interface, trapping multi-host specific methods and generic methods.
java.lang.Object	invokeMore(java.lang.Object proxy, java.lang.reflect.Method method, java.lang.Object[] args) Continuation of the method invocation process, to be implemented within each subclass.
boolean	isClusterTopologyAvailable() Checks if proxy is connected to cluster that can report its topology.
protected boolean	isCurrentConnectionReadOnly()
protected boolean	isCurrentConnectionWriter()
boolean	isFailoverEnabled() Checks if cluster-aware failover is enabled/possible.
protected boolean	isMasterConnection() Checks if current connection is to a master (writer) host.
boolean	isMultiWriterCluster() Checks if proxy is connected to multi-writer cluster.
boolean	isRds() Checks if proxy is connected to RDS-hosted cluster.
boolean	isRdsProxy() Checks if proxy is connected to cluster through RDS proxy.
protected void	pickNewConnection() Picks the "best" connection to use from now on.
protected void	setConnectionProxy(JdbcConnection conn)
protected boolean	shouldExceptionTriggerConnectionSwitch(java.lang.Throwable t) Checks if the given throwable should trigger a connection switch.
protected void	updateTopologyAndConnectIfNeeded(boolean forceUpdate)

Methods inherited from class com.mysql.cj.jdbc.ha.MultiHostConnectionProxy

allowedOnClosedConnection, getNewJdbcInterfaceProxy, getParentProxy, getProxy, invalidateConnection, propagateProxyDown, proxyIfReturnTypeIsJdbcInterface, setProxy, syncSessionState

Methods inherited from class java.lang.Object

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

Field Detail

NULL_LOGGER

protected static final Log NULL_LOGGER

Null logger shared by all connections at startup.

log

protected transient Log log

The logger we're going to use.

DEFAULT_SOCKET_TIMEOUT_MS

protected static final int DEFAULT_SOCKET_TIMEOUT_MS

See Also:

Constant Field Values

DEFAULT_CONNECT_TIMEOUT_MS

protected static final int DEFAULT_CONNECT_TIMEOUT_MS

See Also:

Constant Field Values

NO_CONNECTION_INDEX

protected static final int NO_CONNECTION_INDEX

See Also:

Constant Field Values

WRITER_CONNECTION_INDEX

protected static final int WRITER_CONNECTION_INDEX

See Also:

Constant Field Values

currentHostIndex

protected int currentHostIndex

explicitlyReadOnly

protected java.lang.Boolean explicitlyReadOnly

inTransaction

protected boolean inTransaction

explicitlyAutoCommit

protected boolean explicitlyAutoCommit

isClusterTopologyAvailable

protected boolean isClusterTopologyAvailable

isMultiWriterCluster

protected boolean isMultiWriterCluster

isRdsProxy

protected boolean isRdsProxy

isRds

protected boolean isRds

topologyService

protected TopologyService topologyService

hosts

protected java.util.List<HostInfo> hosts

writerFailoverHandler

protected WriterFailoverHandler writerFailoverHandler

readerFailoverHandler

protected ReaderFailoverHandler readerFailoverHandler

connectionProvider

protected ConnectionProvider connectionProvider

metrics

protected ClusterAwareMetrics metrics

enableFailoverSetting

protected boolean enableFailoverSetting

clusterTopologyRefreshRateMsSetting

protected int clusterTopologyRefreshRateMsSetting

loggerClassNameSetting

protected java.lang.String loggerClassNameSetting

gatherPerfMetricsSetting

protected boolean gatherPerfMetricsSetting

failoverTimeoutMsSetting

protected int failoverTimeoutMsSetting

failoverClusterTopologyRefreshRateMsSetting

protected int failoverClusterTopologyRefreshRateMsSetting

failoverWriterReconnectIntervalMsSetting

protected int failoverWriterReconnectIntervalMsSetting

failoverReaderConnectTimeoutMsSetting

protected int failoverReaderConnectTimeoutMsSetting

clusterIdSetting

protected java.lang.String clusterIdSetting

clusterInstanceHostPatternSetting

protected java.lang.String clusterInstanceHostPatternSetting

failoverConnectTimeoutMs

protected int failoverConnectTimeoutMs

failoverSocketTimeoutMs

protected int failoverSocketTimeoutMs

Constructor Detail

ClusterAwareConnectionProxy

public ClusterAwareConnectionProxy(ConnectionUrl connectionUrl)
                            throws java.sql.SQLException

Instantiates a new AuroraConnectionProxy for the given list of hosts and connection properties.

Parameters:

connectionUrl - ConnectionUrl instance containing the lists of hosts available to switch on.

Throws:

java.sql.SQLException - if an error occurs

Method Detail

autodetectClusterAndCreateProxyInstance

public static JdbcConnection autodetectClusterAndCreateProxyInstance(ConnectionUrl connectionUrl)
                                                              throws java.sql.SQLException

Checks if connection is associated with Aurora cluster and instantiates a new AuroraConnectionProxy if needed. Otherwise it returns a single-host connection.

Parameters:

connectionUrl - ConnectionUrl instance containing the lists of hosts available to switch on.

Throws:

java.sql.SQLException - if an error occurs

createProxyInstance

public static JdbcConnection createProxyInstance(ConnectionUrl connectionUrl)
                                          throws java.sql.SQLException

Instantiates a new AuroraConnectionProxy.

Parameters:

connectionUrl - ConnectionUrl instance containing the lists of hosts available to switch on.

Throws:

java.sql.SQLException - if an error occurs

initSettings

protected void initSettings(ConnectionUrl connectionUrl)
                     throws java.sql.SQLException

Throws:

java.sql.SQLException

initLogger

protected void initLogger()

isClusterTopologyAvailable

public boolean isClusterTopologyAvailable()

Checks if proxy is connected to cluster that can report its topology.

Returns:

true if proxy is connected to cluster that can report its topology

isRds

public boolean isRds()

Checks if proxy is connected to RDS-hosted cluster.

Returns:

true if proxy is connected to RDS-hosted cluster

isRdsProxy

public boolean isRdsProxy()

Checks if proxy is connected to cluster through RDS proxy.

Returns:

true if proxy is connected to cluster through RDS proxy

isMultiWriterCluster

public boolean isMultiWriterCluster()

Checks if proxy is connected to multi-writer cluster.

Returns:

true if proxy is connected to multi-writer cluster

isFailoverEnabled

public boolean isFailoverEnabled()

Checks if cluster-aware failover is enabled/possible.

Returns:

true if cluster-aware failover is enabled

initClusterInfo

protected void initClusterInfo(ConnectionUrl connUrl)
                        throws java.sql.SQLException

Throws:

java.sql.SQLException

createConnectionAndInitializeTopology

protected void createConnectionAndInitializeTopology(ConnectionUrl connUrl)
                                              throws java.sql.SQLException

Throws:

java.sql.SQLException

invalidateCurrentConnection

protected void invalidateCurrentConnection()
                                    throws java.sql.SQLException

Invalidates the current connection.

Overrides:

invalidateCurrentConnection in class MultiHostConnectionProxy

Throws:

java.sql.SQLException - if an error occurs

dealWithInvocationException

protected void dealWithInvocationException(java.lang.reflect.InvocationTargetException e)
                                    throws java.sql.SQLException,
                                           java.lang.Throwable,
                                           java.lang.reflect.InvocationTargetException

Deals with InvocationException from proxied objects.

Overrides:

dealWithInvocationException in class MultiHostConnectionProxy

Parameters:

e - The Exception instance to check.

Throws:

java.sql.SQLException - if an error occurs

java.lang.Throwable - if an error occurs

java.lang.reflect.InvocationTargetException - if an error occurs

shouldExceptionTriggerConnectionSwitch

protected boolean shouldExceptionTriggerConnectionSwitch(java.lang.Throwable t)

Description copied from class: MultiHostConnectionProxy

Checks if the given throwable should trigger a connection switch.

Specified by:

shouldExceptionTriggerConnectionSwitch in class MultiHostConnectionProxy

Parameters:

t - The Throwable instance to analyze.

Returns:

true if the given throwable should trigger a connection switch

isMasterConnection

protected boolean isMasterConnection()

Checks if current connection is to a master (writer) host.

Specified by:

isMasterConnection in class MultiHostConnectionProxy

Returns:

true if current connection is to a master host

pickNewConnection

protected void pickNewConnection()
                          throws java.sql.SQLException

Description copied from class: MultiHostConnectionProxy

Picks the "best" connection to use from now on. Each subclass needs to implement its connection switch strategy on it.

Specified by:

pickNewConnection in class MultiHostConnectionProxy

Throws:

java.sql.SQLException - if an error occurs

createConnectionForHost

protected ConnectionImpl createConnectionForHost(HostInfo hostInfo)
                                          throws java.sql.SQLException

Creates a new physical connection for the given HostInfo.

Overrides:

createConnectionForHost in class MultiHostConnectionProxy

Parameters:

hostInfo - The host info instance.

Returns:

The new Connection instance.

Throws:

java.sql.SQLException - if an error occurs

setConnectionProxy

protected void setConnectionProxy(JdbcConnection conn)

isCurrentConnectionReadOnly

protected boolean isCurrentConnectionReadOnly()

isCurrentConnectionWriter

protected boolean isCurrentConnectionWriter()

failover

protected void failover(int failedHostIdx)
                 throws java.sql.SQLException

Initiates a default failover procedure starting at the given host index. This process tries to connect, sequentially, to the next host in the list. The primary host may or may not be excluded from the connection attempts.

Parameters:

failedHostIdx - The host index where to start from. First connection attempt will be the next one.

Throws:

java.sql.SQLException - if an error occurs

failoverWriter

protected void failoverWriter()
                       throws java.sql.SQLException

Throws:

java.sql.SQLException

failoverReader

protected void failoverReader(int failedHostIdx)
                       throws java.sql.SQLException

Throws:

java.sql.SQLException

doClose

protected void doClose()
                throws java.sql.SQLException

Closes current connection.

Specified by:

doClose in class MultiHostConnectionProxy

Throws:

java.sql.SQLException - if an error occurs

doAbortInternal

protected void doAbortInternal()
                        throws java.sql.SQLException

Aborts current connection.

Specified by:

doAbortInternal in class MultiHostConnectionProxy

Throws:

java.sql.SQLException - if an error occurs

doAbort

protected void doAbort(java.util.concurrent.Executor executor)
                throws java.sql.SQLException

Aborts current connection using the given executor.

Specified by:

doAbort in class MultiHostConnectionProxy

Parameters:

executor - executor

Throws:

java.sql.SQLException - if an error occurs

updateTopologyAndConnectIfNeeded

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

Throws:

java.sql.SQLException

invoke

public java.lang.Object invoke(java.lang.Object proxy,
                               java.lang.reflect.Method method,
                               java.lang.Object[] args)
                        throws java.lang.Throwable

Description copied from class: MultiHostConnectionProxy

Proxies method invocation on the java.sql.Connection interface, trapping multi-host specific methods and generic methods. Subclasses have to override this to complete the method invocation process, deal with exceptions and decide when to switch connection. To avoid unnecessary additional exception handling overriders should consult #canDealWith(Method) before chaining here.

Specified by:

invoke in interface java.lang.reflect.InvocationHandler

Overrides:

invoke in class MultiHostConnectionProxy

Parameters:

proxy - proxy object

method - method to invoke

args - method parameters

Returns:

method result

Throws:

java.lang.Throwable - if an error occurs

invokeMore

public java.lang.Object invokeMore(java.lang.Object proxy,
                                   java.lang.reflect.Method method,
                                   java.lang.Object[] args)
                            throws java.lang.Throwable

Description copied from class: MultiHostConnectionProxy

Continuation of the method invocation process, to be implemented within each subclass.

Specified by:

invokeMore in class MultiHostConnectionProxy

Parameters:

proxy - proxy object

method - method to invoke

args - method parameters

Returns:

method result

Throws:

java.lang.Throwable - if an error occurs

getConnectionLifecycleInterceptor

public ConnectionLifecycleInterceptor getConnectionLifecycleInterceptor()

Specified by:

getConnectionLifecycleInterceptor in interface ConnectionLifecycleInterceptorProvider

getConnection

protected JdbcConnection getConnection()