com.mysql.cj.jdbc.interceptors

Class ServerStatusDiffInterceptor

java.lang.Object

com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor

All Implemented Interfaces:

QueryInterceptor

public class ServerStatusDiffInterceptor
extends java.lang.Object
implements QueryInterceptor

Constructor Summary

Constructors

Constructor and Description
ServerStatusDiffInterceptor()

Method Summary

Modifier and Type	Method and 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.
boolean	executeTopLevelOnly() Should the driver execute this interceptor only for the "original" top-level query, and not put it in the execution path for queries that may be executed from other interceptors? If an interceptor issues queries using the connection it was created for, and does not return true for this method, it must ensure that it does not cause infinite recursion.
QueryInterceptor	init(MysqlConnection conn, java.util.Properties props, Log l) Called once per connection that wants to use the interceptor The properties are the same ones passed in in the URL or arguments to Driver.connect() or DriverManager.getConnection().
<T extends Resultset> T	postProcess(java.util.function.Supplier<java.lang.String> sql, Query interceptedQuery, T originalResultSet, ServerSession serverSession) Called after the given query has been sent to the server for processing.
<T extends Resultset> T	preProcess(java.util.function.Supplier<java.lang.String> sql, Query interceptedQuery) Called before the given query is going to be sent to the server for processing.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.mysql.cj.interceptors.QueryInterceptor

postProcess, preProcess

Constructor Detail

ServerStatusDiffInterceptor

public ServerStatusDiffInterceptor()

Method Detail

init

public QueryInterceptor init(MysqlConnection conn,
                             java.util.Properties props,
                             Log l)

Description copied from interface: QueryInterceptor

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

Specified by:

init in interface QueryInterceptor

Parameters:

conn - the connection for which this interceptor 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. QueryInterceptor properties are not exposed via accessor/mutator methods on DataSources.

l - logger

Returns:

QueryInterceptor

postProcess

public <T extends Resultset> T postProcess(java.util.function.Supplier<java.lang.String> sql,
                                           Query interceptedQuery,
                                           T originalResultSet,
                                           ServerSession serverSession)

Description copied from interface: QueryInterceptor

Called after the given query has been sent to the server for processing. Interceptors are free to inspect the "original" result set, and if a different result set is returned by the interceptor, it is used in place of the "original" result set. This method will be called while the connection-level mutex is held, so it will only be called from one thread at a time.

Specified by:

postProcess in interface QueryInterceptor

Type Parameters:

T - Resultset object

Parameters:

sql - the Supplier for SQL representation of the query

interceptedQuery - the actual Query instance being intercepted

originalResultSet - a Resultset created from query execution

serverSession - ServerSession object after the query execution

Returns:

a Resultset that should be returned to the application instead of results that are created from actual execution of the intercepted query.

preProcess

public <T extends Resultset> T preProcess(java.util.function.Supplier<java.lang.String> sql,
                                          Query interceptedQuery)

Description copied from interface: QueryInterceptor

Called before the given query is going to be sent to the server for processing. Interceptors are free to return a result set (which must implement the interface Resultset), and if so, the server will not execute the query, and the given result set will be returned to the application instead. This method will be called while the connection-level mutex is held, so it will only be called from one thread at a time.

Specified by:

preProcess in interface QueryInterceptor

Type Parameters:

T - Resultset object

Parameters:

sql - the Supplier for SQL representation of the query

interceptedQuery - the actual Query instance being intercepted

Returns:

a Resultset that should be returned to the application instead of results that are created from actual execution of the intercepted query.

executeTopLevelOnly

public boolean executeTopLevelOnly()

Description copied from interface: QueryInterceptor

Should the driver execute this interceptor only for the "original" top-level query, and not put it in the execution path for queries that may be executed from other interceptors? If an interceptor issues queries using the connection it was created for, and does not return true for this method, it must ensure that it does not cause infinite recursion.

Specified by:

executeTopLevelOnly in interface QueryInterceptor

Returns:

true if the driver should ensure that this interceptor is only executed for the top-level "original" query.

destroy

public void destroy()

Description copied from interface: QueryInterceptor

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 QueryInterceptor