Class RandomBalanceStrategy

java.lang.Object

com.mysql.jdbc.RandomBalanceStrategy

All Implemented Interfaces:

BalanceStrategy, Extension

Direct Known Subclasses:

ServerAffinityStrategy

public class RandomBalanceStrategy
extends Object
implements BalanceStrategy

Constructor Summary

Constructors

Constructor	Description
RandomBalanceStrategy()

Method Summary

Modifier and Type	Method	Description
void	destroy()	Called by the driver when this extension should release any resources it is holding and cleanup internally before the connection is closed.
void	init(Connection conn, Properties props)	Called once per connection that wants to use the extension The properties are the same ones passed in in the URL or arguments to Driver.connect() or DriverManager.getConnection().
ConnectionImpl	pickConnection(LoadBalancedConnectionProxy proxy, List<String> configuredHosts, Map<String, ConnectionImpl> liveConnections, long[] responseTimes, int numRetries)	Called by the driver to pick a new connection to route requests over.

Methods inherited from class Object

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

Constructor Details

RandomBalanceStrategy

public RandomBalanceStrategy()

Method Details

destroy

public void destroy()

Description copied from interface: Extension

Called by the driver when this extension should release any resources it is holding and cleanup internally before the connection is closed.

Specified by:

destroy in interface Extension

init

public void init(Connection conn,
 Properties props)
          throws SQLException

Description copied from interface: Extension

Called once per connection that wants to use the extension The properties are the same ones passed in in the URL or arguments to Driver.connect() or DriverManager.getConnection().

Specified by:

init in interface Extension

Parameters:

conn - the connection for which this extension is being created

props - configuration values as passed to the connection. Note that in order to support javax.sql.DataSources, configuration properties specific to an interceptor must be passed via setURL() on the DataSource. Extension properties are not exposed via accessor/mutator methods on DataSources.

Throws:

SQLException - should be thrown if the the Extension can not initialize itself.

pickConnection

public ConnectionImpl pickConnection(LoadBalancedConnectionProxy proxy,
 List<String> configuredHosts,
 Map<String, ConnectionImpl> liveConnections,
 long[] responseTimes,
 int numRetries)
                              throws SQLException

Description copied from interface: BalanceStrategy

Called by the driver to pick a new connection to route requests over.

Specified by:

pickConnection in interface BalanceStrategy

Parameters:

proxy - the InvocationHandler that deals with actual method calls to the JDBC connection, and serves as a factory for new connections for this strategy via the createConnectionForHost() method. This proxy takes care of maintaining the response time list, map of host/ports to live connections, and taking connections out of the live connections map if they receive a network-related error while they are in use by the application.

configuredHosts - the list of hosts/ports (in "host:port" form) as passed in by the user.

liveConnections - a map of host/ports to "live" connections to them.

responseTimes - the list of response times for a transaction for each host in the configured hosts list.

numRetries - the number of times the driver expects this strategy to re-try connection attempts if creating a new connection fails.

Returns:

the physical JDBC connection for the application to use, based upon the strategy employed.

Throws:

SQLException - if a new connection can not be found or created by this strategy.

See Also:

• LoadBalancedConnectionProxy.createConnectionForHost(String)