Appendix A: List of ItemReaders and ItemWriters

Item Readers

Item Reader	Description
AbstractItemCountingItemStreamItemReader	Abstract base class that provides basic restart capabilities by counting the number of items returned from an ItemReader.
AggregateItemReader	An ItemReader that delivers a list as its item, storing up objects from the injected ItemReader until they are ready to be packed out as a collection. This class must be used as a wrapper for a custom ItemReader that can identify the record boundaries. The custom reader should mark the beginning and end of records by returning an AggregateItem which responds true to its query methods isHeader() and isFooter(). Note that this reader is not part of the library of readers provided by Spring Batch but given as a sample in spring-batch-samples.
AmqpItemReader	Given a Spring AmqpTemplate, it provides synchronous receive methods. The receiveAndConvert() method lets you receive POJO objects.
KafkaItemReader	An ItemReader that reads messages from an Apache Kafka topic. It can be configured to read messages from multiple partitions of the same topic. This reader stores message offsets in the execution context to support restart capabilities.
FlatFileItemReader	Reads from a flat file. Includes ItemStreamand Skippable functionality. See FlatFileItemReader.
HibernateCursorItemReader	Reads from a cursor based on an HQL query. SeeCursor-based ItemReaders.
HibernatePagingItemReader	Reads from a paginated HQL query
ItemReaderAdapter	Adapts any class to theItemReader interface.
JdbcCursorItemReader	Reads from a database cursor via JDBC. SeeCursor-based ItemReaders.
JdbcPagingItemReader	Given an SQL statement, pages through the rows, such that large datasets can be read without running out of memory.
JmsItemReader	Given a Spring JmsOperations object and a JMS Destination or destination name to which to send errors, provides items received through the injected JmsOperations#receive()method.
JpaPagingItemReader	Given a JPQL statement, pages through the rows, such that large datasets can be read without running out of memory.
ListItemReader	Provides the items from a list, one at a time.
MongoItemReader	Given a MongoOperations object and a JSON-based MongoDB query, provides items received from the MongoOperations#find() method.
Neo4jItemReader	Given a Neo4jOperations object and the components of a Cyhper query, items are returned as the result of the Neo4jOperations.query method.
RepositoryItemReader	Given a Spring Data PagingAndSortingRepository object, a Sort, and the name of method to execute, returns items provided by the Spring Data repository implementation.
StoredProcedureItemReader	Reads from a database cursor resulting from the execution of a database stored procedure. See StoredProcedureItemReader
StaxEventItemReader	Reads via StAX. see StaxEventItemReader.
JsonItemReader	Reads items from a Json document. see JsonItemReader.

Item Writers

Item Writer	Description
AbstractItemStreamItemWriter	Abstract base class that combines theItemStream andItemWriter interfaces.
AmqpItemWriter	Given a Spring AmqpTemplate, it provides for a synchronous send method. The convertAndSend(Object)method lets you send POJO objects.
CompositeItemWriter	Passes an item to the write method of each in an injected List of ItemWriter objects.
FlatFileItemWriter	Writes to a flat file. Includes ItemStream and Skippable functionality. See FlatFileItemWriter.
GemfireItemWriter	Using a GemfireOperations object, items are either written or removed from the Gemfire instance based on the configuration of the delete flag.
HibernateItemWriter	This item writer is Hibernate-session aware and handles some transaction-related work that a non-"hibernate-aware" item writer would not need to know about and then delegates to another item writer to do the actual writing.
ItemWriterAdapter	Adapts any class to theItemWriter interface.
JdbcBatchItemWriter	Uses batching features from aPreparedStatement, if available, and can take rudimentary steps to locate a failure during aflush.
JmsItemWriter	Using a JmsOperations object, items are written to the default queue through the JmsOperations#convertAndSend() method.
JpaItemWriter	This item writer is JPA EntityManager-aware and handles some transaction-related work that a non-"JPA-aware"ItemWriter would not need to know about and then delegates to another writer to do the actual writing.
KafkaItemWriter	Using a KafkaTemplate object, items are written to the default topic through theKafkaTemplate#sendDefault(Object, Object) method using a Converter to map the key from the item. A delete flag can also be configured to send delete events to the topic.
MimeMessageItemWriter	Using Spring’s JavaMailSender, items of type MimeMessageare sent as mail messages.
MongoItemWriter	Given a MongoOperations object, items are written through the MongoOperations.save(Object) method. The actual write is delayed until the last possible moment before the transaction commits.
Neo4jItemWriter	Given a Neo4jOperations object, items are persisted through thesave(Object) method or deleted through the delete(Object) per theItemWriter’s configuration
PropertyExtractingDelegatingItemWriter	Extends AbstractMethodInvokingDelegatorcreating arguments on the fly. Arguments are created by retrieving the values from the fields in the item to be processed (through aSpringBeanWrapper), based on an injected array of field names.
RepositoryItemWriter	Given a Spring Data CrudRepository implementation, items are saved through the method specified in the configuration.
StaxEventItemWriter	Uses a Marshaller implementation to convert each item to XML and then writes it to an XML file using StAX.
JsonFileItemWriter	Uses a JsonObjectMarshaller implementation to convert each item to Json and then writes it to an Json file.