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QgsConnectionPool< T, T_Group > Class Template Reference

Template class responsible for keeping a pool of open connections. More...

#include <qgsconnectionpool.h>

Public Types

typedef QMap< QString, T_Group * > T_Groups

Public Member Functions

acquireConnection (const QString &connInfo)
 Try to acquire a connection: if no connections are available, the thread will get blocked.
void releaseConnection (T conn)
 Release an existing connection so it will get back into the pool and can be reused.

Protected Attributes

T_Groups mGroups

Detailed Description

template<typename T, typename T_Group>
class QgsConnectionPool< T, T_Group >

Template class responsible for keeping a pool of open connections.

This is desired to avoid the overhead of creation of new connection everytime.

The methods are thread safe.

The connection pool has a limit on maximum number of concurrent connections (per server), once the limit is reached, the acquireConnection() function will block. All connections that have been acquired must be then released with releaseConnection() function.

When the connections are not used for some time, they will get closed automatically to save resources.

Definition at line 199 of file qgsconnectionpool.h.

Member Typedef Documentation

template<typename T , typename T_Group >
typedef QMap<QString, T_Group*> QgsConnectionPool< T, T_Group >::T_Groups

Definition at line 203 of file qgsconnectionpool.h.

Member Function Documentation

template<typename T , typename T_Group >
T QgsConnectionPool< T, T_Group >::acquireConnection ( const QString &  connInfo)
inline

Try to acquire a connection: if no connections are available, the thread will get blocked.

Returns
initialized connection or null on error

Definition at line 207 of file qgsconnectionpool.h.

template<typename T , typename T_Group >
void QgsConnectionPool< T, T_Group >::releaseConnection ( conn)
inline

Release an existing connection so it will get back into the pool and can be reused.

Definition at line 222 of file qgsconnectionpool.h.

Member Data Documentation

template<typename T , typename T_Group >
T_Groups QgsConnectionPool< T, T_Group >::mGroups
protected

Definition at line 234 of file qgsconnectionpool.h.


The documentation for this class was generated from the following file: