Package org.springframework.batch.item.xml

Class StaxEventItemWriter<T>

java.lang.Object
org.springframework.batch.item.ItemStreamSupport
org.springframework.batch.item.support.AbstractItemStreamItemWriter<T>
org.springframework.batch.item.xml.StaxEventItemWriter<T>
All Implemented Interfaces:
ResourceAwareItemWriterItemStream<T>, ItemStream, ItemStreamWriter<T>, ItemWriter<T>, org.springframework.beans.factory.InitializingBean
public class StaxEventItemWriter<T> extends AbstractItemStreamItemWriter<T> implements ResourceAwareItemWriterItemStream<T>, org.springframework.beans.factory.InitializingBean
An implementation of ItemWriter which uses StAX and Marshaller for serializing object to XML.

This item writer also provides restart, statistics and transaction features by implementing corresponding interfaces.

The implementation is not thread-safe.

Author:
Peter Zozom, Robert Kasanicky, Michael Minella, Parikshit Dutta, Mahmoud Ben Hassine

  • Field Details

  • Constructor Details

    • StaxEventItemWriter

      public StaxEventItemWriter()

  • Method Details

    • setResource

      public void setResource(org.springframework.core.io.WritableResource resource)
      Set output file.
      Specified by:
      setResource in interface ResourceAwareItemWriterItemStream<T>
      Parameters:
      resource - the output file

    • setMarshaller

      public void setMarshaller(org.springframework.oxm.Marshaller marshaller)
      Set Object to XML marshaller.
      Parameters:
      marshaller - the Object to XML marshaller

    • setHeaderCallback

      public void setHeaderCallback(StaxWriterCallback headerCallback)
      headerCallback is called before writing any items.
      Parameters:
      headerCallback - the StaxWriterCallback to be called prior to writing items.

    • setFooterCallback

      public void setFooterCallback(StaxWriterCallback footerCallback)
      footerCallback is called after writing all items but before closing the file.
      Parameters:
      footerCallback - the StaxWriterCallback to be called after writing items.

    • setTransactional

      public void setTransactional(boolean transactional)
      Flag to indicate that writes should be deferred to the end of a transaction if present. Defaults to true.
      Parameters:
      transactional - the flag to set

    • setForceSync

      public void setForceSync(boolean forceSync)
      Flag to indicate that changes should be force-synced to disk on flush. Defaults to false, which means that even with a local disk changes could be lost if the OS crashes in between a write and a cache flush. Setting to true may result in slower performance for usage patterns involving many frequent writes.
      Parameters:
      forceSync - the flag value to set

    • setShouldDeleteIfEmpty

      public void setShouldDeleteIfEmpty(boolean shouldDeleteIfEmpty)
      Flag to indicate that the target file should be deleted if no items have been written (other than header and footer) on close. Defaults to false.
      Parameters:
      shouldDeleteIfEmpty - the flag value to set

    • getEncoding

      public String getEncoding()
      Get used encoding.
      Returns:
      the encoding used

    • setEncoding

      public void setEncoding(String encoding)
      Set encoding to be used for output file.
      Parameters:
      encoding - the encoding to be used

    • getVersion

      public String getVersion()
      Get XML version.
      Returns:
      the XML version used

    • setVersion

      public void setVersion(String version)
      Set XML version to be used for output XML.
      Parameters:
      version - the XML version to be used

    • getStandalone

      public Boolean getStandalone()
      Get used standalone document declaration.
      Returns:
      the standalone document declaration used
      Since:
      4.3

    • setStandalone

      public void setStandalone(Boolean standalone)
      Set standalone document declaration to be used for output XML. If not set, standalone document declaration will be omitted.
      Parameters:
      standalone - the XML standalone document declaration to be used
      Since:
      4.3

    • getRootTagName

      public String getRootTagName()
      Get the tag name of the root element.
      Returns:
      the root element tag name

    • setRootTagName

      public void setRootTagName(String rootTagName)
      Set the tag name of the root element. If not set, default name is used ("root"). Namespace URI and prefix can also be set optionally using the notation: 
       {uri}prefix:root
      The prefix is optional (defaults to empty), but if it is specified then the uri must be provided. In addition you might want to declare other namespaces using the root attributes.
      Parameters:
      rootTagName - the tag name to be used for the root element

    • getRootTagNamespacePrefix

      public String getRootTagNamespacePrefix()
      Get the namespace prefix of the root element. Empty by default.
      Returns:
      the rootTagNamespacePrefix

    • getRootTagNamespace

      public String getRootTagNamespace()
      Get the namespace of the root element.
      Returns:
      the rootTagNamespace

    • getRootElementAttributes

      public Map<String,String> getRootElementAttributes()
      Get attributes of the root element.
      Returns:
      attributes of the root element

    • setRootElementAttributes

      public void setRootElementAttributes(Map<String,String> rootElementAttributes)
      Set the root element attributes to be written. If any of the key names begin with "xmlns:" then they are treated as namespace declarations.
      Parameters:
      rootElementAttributes - attributes of the root element

    • setOverwriteOutput

      public void setOverwriteOutput(boolean overwriteOutput)
      Set "overwrite" flag for the output file. Flag is ignored when output file processing is restarted.
      Parameters:
      overwriteOutput - If set to true, output file will be overwritten (this flag is ignored when processing is restart).

    • setSaveState

      public void setSaveState(boolean saveState)

    • afterPropertiesSet

      public void afterPropertiesSet() throws Exception
      Specified by:
      afterPropertiesSet in interface org.springframework.beans.factory.InitializingBean
      Throws:
      Exception - thrown if error occurs
      See Also:
      • InitializingBean.afterPropertiesSet()

    • open

      public void open(ExecutionContext executionContext)
      Open the output source
      Specified by:
      open in interface ItemStream
      Overrides:
      open in class ItemStreamSupport
      Parameters:
      executionContext - the batch context.
      See Also:

    • createXmlEventWriter

      protected XMLEventWriter createXmlEventWriter(XMLOutputFactory outputFactory, Writer writer) throws XMLStreamException
      Subclasses can override to customize the writer.
      Parameters:
      outputFactory - the factory to be used to create an XMLEventWriter.
      writer - the Writer to be used by the XMLEventWriter for writing to character streams.
      Returns:
      an xml writer
      Throws:
      XMLStreamException - thrown if error occured creating XMLEventWriter.

    • createXmlOutputFactory

      protected XMLOutputFactory createXmlOutputFactory() throws FactoryConfigurationError
      Subclasses can override to customize the factory.
      Returns:
      a factory for the xml output
      Throws:
      FactoryConfigurationError - throw if an instance of this factory cannot be loaded.

    • createXmlEventFactory

      protected XMLEventFactory createXmlEventFactory() throws FactoryConfigurationError
      Subclasses can override to customize the event factory.
      Returns:
      a factory for the xml events
      Throws:
      FactoryConfigurationError - thrown if an instance of this factory cannot be loaded.

    • createStaxResult

      protected Result createStaxResult()
      Subclasses can override to customize the STAX result.
      Returns:
      a result for writing to

    • initNamespaceContext

      protected void initNamespaceContext(XMLEventWriter writer) throws XMLStreamException
      Inits the namespace context of the XMLEventWriter:
      • rootTagNamespacePrefix for rootTagName
      • any other xmlns namespace prefix declarations in the root element attributes
      Parameters:
      writer - XML event writer
      Throws:
      XMLStreamException - thrown if error occurs while setting the prefix or default name space.

    • startDocument

      protected void startDocument(XMLEventWriter writer) throws XMLStreamException
      Writes simple XML header containing:
      • xml declaration - defines encoding and XML version
      • opening tag of the root element and its attributes
      If this is not sufficient for you, simply override this method. Encoding, version and root tag name can be retrieved with corresponding getters.
      Parameters:
      writer - XML event writer
      Throws:
      XMLStreamException - thrown if error occurs.

    • endDocument

      protected void endDocument(XMLEventWriter writer) throws XMLStreamException
      Writes the EndDocument tag manually.
      Parameters:
      writer - XML event writer
      Throws:
      XMLStreamException - thrown if error occurs.

    • close

      public void close()
      Flush and close the output source.
      Specified by:
      close in interface ItemStream
      Overrides:
      close in class ItemStreamSupport
      See Also:

    • write

      public void write(Chunk<? extends T> items) throws org.springframework.oxm.XmlMappingException, IOException
      Write the value objects and flush them to the file.
      Specified by:
      write in interface ItemWriter<T>
      Parameters:
      items - the value object
      Throws:
      IOException - thrown if general error occurs.
      org.springframework.oxm.XmlMappingException - thrown if error occurs during XML Mapping.

    • update

      public void update(ExecutionContext executionContext)
      Get the restart data.
      Specified by:
      update in interface ItemStream
      Overrides:
      update in class ItemStreamSupport
      Parameters:
      executionContext - the batch context.
      See Also: