com.inet.report.cache
Class ExternalDBCache

java.lang.Object
  com.inet.report.cache.Cache
      com.inet.report.cache.ExternalDBCache

public class ExternalDBCache
extends Cache

This class implements a database cache without a connection factory. This means that the connections have to be set from an external program. These methods can be use together with the cache type "External Database Cache", only.

Since:

7.5

See Also:

Cache.TYPE_EXTERNAL_DATABASE

Field Summary

Fields inherited from class com.inet.report.cache.Cache

TYPE_DATABASE, TYPE_EXTERNAL_DATABASE, TYPE_HARDDISK, TYPE_MEMORY

Method Summary

static void	addConnection(java.sql.Connection conn) Adds a connection to the pool for the External Database Cache.
static void	checkConnections(java.lang.String jndiName) Checks whether the database pool for caching has enough connections.
static boolean	isConnectionNeeded() Checks whether the External Database Cache need more connections.

Methods inherited from class com.inet.report.cache.Cache

addEngine, createKey, createKey, createKey, delete, delete, exists, getCache, getEngineFactory, getFailureCause, getKey, getKey, getKey, getPageAndWait, getPageAndWait, getPageCountAndWait, getPageCountAndWait, getReports, getTotalPageSizeAndWait, getTotalPageSizeAndWait, getType, isFailedReport, isFinishWrittenToStore, isFinished, isPageLimitExceeded, isScheduleReport, isTypeSchedulerCache, lock, resetCacheTimeout, setEngineFactory, setSchedule, unlock

Method Detail

isConnectionNeeded

public static boolean isConnectionNeeded()
                                  throws ReportException

Checks whether the External Database Cache need more connections. The typical use is:

 while(ExternalDBCache.isConnectionNeeded()){
     Connection conn = myConnectionFactory();
     ExternalDBCache.addConnection(conn);
 }

Returns:

true if the cache need more connections

Throws:

ReportException - If the current cache type ID is not ExternalDBCache

Since:

7.5

See Also:

addConnection(java.sql.Connection), Cache.TYPE_EXTERNAL_DATABASE

addConnection

public static void addConnection(java.sql.Connection conn)
                          throws ReportException

Adds a connection to the pool for the External Database Cache. This connection should be a long-term connection, open as long as possible. It should be accessible from another thread.

Parameters:

conn - a new JDBC connection

Throws:

ReportException - If the current cache type ID is not ExternalDBCache

Since:

7.5

See Also:

isConnectionNeeded(), Cache.TYPE_EXTERNAL_DATABASE

checkConnections

public static void checkConnections(java.lang.String jndiName)
                             throws ReportException

Checks whether the database pool for caching has enough connections. If not, then it creates a new connection for the specified JNDI name and add it to the pool. If you use the External Database Cache together with JNDI then you should call this method before rendering a report.
This can be done in the servlet method service(), for example.

Parameters:

jndiName - the JNDI name of the datasource that the cache should use.

Throws:

ReportException - If the current cache type ID is not ExternalDBCache

Since:

7.5

See Also:

Cache.TYPE_EXTERNAL_DATABASE