net.sf.jasperreports.engine.query
Interface JRQueryExecuter

All Known Implementing Classes:

JaxenXPathQueryExecuter, JRAbstractQueryExecuter, JRCsvQueryExecuter, JREmptyQueryExecuter, JRHibernateQueryExecuter, JRJdbcQueryExecuter, JRJpaQueryExecuter, JRMondrianQueryExecuter, JRXlsQueryExecuter, JRXlsxQueryExecuter, JRXmlaQueryExecuter, JRXPathQueryExecuter, JsonQueryExecuter, XalanXPathQueryExecuter

public interface JRQueryExecuter

Query executer interface.

An implementation of this interface is created when the input data of a report/dataset is specified by a query.

The implementation will run the query and create a JRDataSource from the result.

The query executers would usually be initialized by a JRQueryExecuterFactory with the query and the parameter values.

Version:

$Id: JRQueryExecuter.java 4595 2011-09-08 15:55:10Z teodord $

Author:

Lucian Chirita ([email protected])

See Also:

JRQueryExecuterFactory

Method Summary

boolean	cancelQuery() Cancels the query if it's currently running.
void	close() Closes resources kept open during the data source iteration.
JRDataSource	createDatasource() Executes the query and creates a JRDataSource out of the result.

Method Detail

createDatasource

JRDataSource createDatasource()
                              throws JRException

Executes the query and creates a JRDataSource out of the result.

Returns:

a JRDataSource wrapping the query execution result.

Throws:

JRException

close

void close()

Closes resources kept open during the data source iteration.

This method is called after the report is filled or the dataset is iterated. If a resource is not needed after the data source has been created, it should be released at the end of createDatasource.

cancelQuery

boolean cancelQuery()
                    throws JRException

Cancels the query if it's currently running.

This method will be called from a different thread if the client decides to cancel the filling process.

Returns:

true if and only if the query was running and it has been canceled

Throws:

JRException