Package org.axonframework.messaging.eventhandling.deadletter.jdbc

Class PagingJdbcIterable<R>

java.lang.Object

org.axonframework.messaging.eventhandling.deadletter.jdbc.PagingJdbcIterable<R>

Type Parameters:

R - The mapped result type.

All Implemented Interfaces:

Iterable<R>

@Internal
public class PagingJdbcIterable<R>
extends Object
implements Iterable<R>

Enables iterating through a JDBC query using paging. Paging is taken care of automatically through the provided PagingJdbcIterable.PagingStatementSupplier, fetching the next page when the items run out to iterate through.

Do not use this for paging when you care about concurrent deletes. If you loaded a page, delete an item from it, and load the next, you will miss an item during iteration.

The iterator() function can be called multiple times to loop through the items, restarting the query from the start.

Since:

4.8.0

Author:

Mitchell Herrijgers, Steven van Beelen

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	PagingJdbcIterable.PagingIterator	The Iterator that loops through the provided query's pages until it runs out of items.
static interface	PagingJdbcIterable.PagingStatementSupplier	Describes a function that creates a new PreparedStatement that pages results through the given offset and maxSize, ready to be executed.

Constructor Summary

Constructors

Constructor	Description
PagingJdbcIterable(TransactionalExecutor<Connection> executor, PagingJdbcIterable.PagingStatementSupplier pagingQuerySupplier, int pageSize, Duration queryTimeout, JdbcUtils.SqlResultConverter<R> resultConverter, Function<SQLException,RuntimeException> errorHandler)	Construct a new Iterable of type R, utilizing paging queries to retrieve the entries.
PagingJdbcIterable(TransactionalExecutor<Connection> executor, PagingJdbcIterable.PagingStatementSupplier pagingQuerySupplier, int pageSize, JdbcUtils.SqlResultConverter<R> resultConverter, Function<SQLException,RuntimeException> errorHandler)	Construct a new Iterable of type R, utilizing paging queries to retrieve the entries.

Method Summary

Modifier and Type	Method	Description
Iterator<R>	iterator()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Details

PagingJdbcIterable

public PagingJdbcIterable(TransactionalExecutor<Connection> executor,
 PagingJdbcIterable.PagingStatementSupplier pagingQuerySupplier,
 int pageSize,
 JdbcUtils.SqlResultConverter<R> resultConverter,
 Function<SQLException,RuntimeException> errorHandler)

Construct a new Iterable of type R, utilizing paging queries to retrieve the entries.

Uses a default query timeout of 30 seconds per page fetch.

Parameters:

executor - The TransactionalExecutor used to execute the paging query.

pagingQuerySupplier - A factory function supply the paging PreparedStatement to execute.

pageSize - The size of the pages to retrieve. Used to calculate the offset and maxSize of the paging query

resultConverter - The converter of the ResultSet into entries of type R.

errorHandler - The error handler to deal with exceptions when executing a paging PreparedStatement.

PagingJdbcIterable

public PagingJdbcIterable(TransactionalExecutor<Connection> executor,
 PagingJdbcIterable.PagingStatementSupplier pagingQuerySupplier,
 int pageSize,
 Duration queryTimeout,
 JdbcUtils.SqlResultConverter<R> resultConverter,
 Function<SQLException,RuntimeException> errorHandler)

Construct a new Iterable of type R, utilizing paging queries to retrieve the entries.

Parameters:

executor - The TransactionalExecutor used to execute the paging query.

pagingQuerySupplier - A factory function supply the paging PreparedStatement to execute.

pageSize - The size of the pages to retrieve. Used to calculate the offset and maxSize of the paging query

queryTimeout - The maximum time to wait for each page query to complete.

resultConverter - The converter of the ResultSet into entries of type R.

errorHandler - The error handler to deal with exceptions when executing a paging PreparedStatement.

Method Details

iterator

public Iterator<R> iterator()

Specified by:

iterator in interface Iterable<R>