javax.xml.bind
Interface Unmarshaller

All Known Subinterfaces:

JMUnmarshaller

All Known Implementing Classes:

AbstractUnmarshallerImpl, JMUnmarshallerImpl

public interface Unmarshaller

A Unmarshaller is the opposite of the Marshaller: It takes as input XML in either of several representations (byte or character stream, DOM node, or a series of SAX events) and returns a JAXB object with the same contents.

If the JAXB user demands, the Unmarshaller may also validate the content tree that it sees.

Since:

JAXB1.0

Author:

JSR-31

See Also:

JAXBContext, Marshaller, Validator

Method Summary

ValidationEventHandler	getEventHandler() If the JAXB application has registered a custom handler for validation events, returns that handler.
java.lang.Object	getProperty(java.lang.String pName) Returnss the unmarshaller property pName to the value pValue.
UnmarshallerHandler	getUnmarshallerHandler() Returns a SAX 2 ContentHandler, which is able to parse a SAX event stream and convert it into a JAXB object.
boolean	isValidating() Sets whether the Unmarshaller is validating the objects that it reads.
void	setEventHandler(ValidationEventHandler pHandler) An application may customize the Unmarshallers behaviour in case of validation problems by supplying a custom handler for validation events.
void	setProperty(java.lang.String pName, java.lang.Object pValue) Sets the unmarshaller property pName to the value pValue.
void	setValidating(boolean pValidating) Sets whether the Unmarshaller is validating the objects that it reads.
java.lang.Object	unmarshal(java.io.File pFile) This method takes opens the given file pFile for input.
java.lang.Object	unmarshal(org.xml.sax.InputSource pSource) The Unmarshaller reads the byte stream or character stream referred by the InputSource and converts it into an equivalent JAXB object.
java.lang.Object	unmarshal(java.io.InputStream pStream) The Unmarshaller reads the given byte stream and converts it into an equivalent JAXB object.
java.lang.Object	unmarshal(org.w3c.dom.Node pNode) The Unmarshaller converts the given node into an equivalent JAXB object.
java.lang.Object	unmarshal(javax.xml.transform.Source pSource) The Unmarshaller reads the XML representation from the given Source and converts it into an equivalent JAXB object.
java.lang.Object	unmarshal(java.net.URL pURL) This method takes connects to the given pURL and opens a byte stream for input.

Method Detail

unmarshal

java.lang.Object unmarshal(java.io.File pFile)
                           throws JAXBException

This method takes opens the given file pFile for input. The Unmarshaller reads the byte stream contained in the file and converts it into an equivalent JAXB object.

Parameters:

pFile - The file being read.

Returns:

The JAXB object read from the file.

Throws:

JAXBException - An unexpected problem (for example an IOException) occurred.

UnmarshalException - The JAXB object is invalid or could not be read from the byte stream for similar reasons.

java.lang.IllegalArgumentException - The parameter was null.

unmarshal

java.lang.Object unmarshal(java.io.InputStream pStream)
                           throws JAXBException

The Unmarshaller reads the given byte stream and converts it into an equivalent JAXB object.

Parameters:

pStream - The stream being read.

Returns:

The JAXB object read from the byte stream.

Throws:

JAXBException - An unexpected problem (for example an IOException) occurred.

UnmarshalException - The JAXB object is invalid or could not be read from the byte stream for similar reasons.

java.lang.IllegalArgumentException - The parameter was null.

unmarshal

java.lang.Object unmarshal(java.net.URL pURL)
                           throws JAXBException

This method takes connects to the given pURL and opens a byte stream for input. The Unmarshaller reads the byte stream and converts it into an equivalent JAXB object.

Parameters:

pURL - The URL being read.

Returns:

The JAXB object read from the URL.

Throws:

JAXBException - An unexpected problem (for example an IOException) occurred.

UnmarshalException - The JAXB object is invalid or could not be read from the byte stream for similar reasons.

java.lang.IllegalArgumentException - The parameter was null.

unmarshal

java.lang.Object unmarshal(org.xml.sax.InputSource pSource)
                           throws JAXBException

The Unmarshaller reads the byte stream or character stream referred by the InputSource and converts it into an equivalent JAXB object.

Parameters:

pSource - The InputSource referring to a byte or character stream. It is recommended, that the system ID is set. This may be required, if the XML in the stream refers to external entities.

Returns:

The JAXB object read from the byte or character stream.

Throws:

JAXBException - An unexpected problem (for example an IOException) occurred.

UnmarshalException - The JAXB object is invalid or could not be read from the byte stream for similar reasons.

java.lang.IllegalArgumentException - The parameter was null.

unmarshal

java.lang.Object unmarshal(org.w3c.dom.Node pNode)
                           throws JAXBException

The Unmarshaller converts the given node into an equivalent JAXB object.

Parameters:

pNode - The node to convert. The JAXB provider must support documents and elements. Other node types may not work (document fragments) or cannot work (attributes, text nodes, and so on).

Returns:

The JAXB object read from the DOM node.

Throws:

JAXBException - An unexpected problem occurred.

UnmarshalException - The JAXB object is invalid or could not be read for similar reasons.

java.lang.IllegalArgumentException - The parameter was null.

unmarshal

java.lang.Object unmarshal(javax.xml.transform.Source pSource)
                           throws JAXBException

The Unmarshaller reads the XML representation from the given Source and converts it into an equivalent JAXB object.

The JAXB provider must support at least SAXSource, DOMSource, and StreamSource. A possible implementation could validate whether the argument is actually an instance of these subinterfaces. If so, it might simply act like getUnmarshallerHandler(), unmarshal(org.w3c.dom.Node), unmarshal(java.io.InputStream), or unmarshal(org.xml.sax.InputSource), respectively.

Note: If you are not using the standard JAXP mechanism for obtaining an XMLReader, then you might create your own SAX parser and invoke the pSource arguments SAXSource.setXMLReader(org.xml.sax.XMLReader). The JAXB provider will detect and use your SAX parser.

Parameters:

pSource - The Source being read.

Returns:

The JAXB object read from the DOM node.

Throws:

JAXBException - An unexpected problem occurred.

UnmarshalException - The JAXB object is invalid or could not be read for similar reasons.

java.lang.IllegalArgumentException - The parameter was null.

getUnmarshallerHandler

UnmarshallerHandler getUnmarshallerHandler()
                                           throws JAXBException

Returns a SAX 2 ContentHandler, which is able to parse a SAX event stream and convert it into a JAXB object. This is particularly useful in a stack of SAX handlers. (Think of Apache Cocoon.)

Note: The JAXB provider may choose to return the same handler again, if the method is invoked more than once. In other words, if you need to have multiple handlers (for example, because you have multiple threads), then you should create multiple Unmarshallers.

Throws:

JAXBException

setValidating

void setValidating(boolean pValidating)
                   throws JAXBException

Sets whether the Unmarshaller is validating the objects that it reads. The default is false.

Note: A validating unmarshaller will rarely use a validating SAX parser by default! It does so, because the SAX parsers validation and the Unmarshallers builtin validation would most probably validate the same things, resulting in no additional safety at the cost of wasting performance. Second, a SAX parser is not always in use. For example, you do not need a parser when converting a DOM Node. If you insist in a validating XML parser, then you should create your own XMLReader and use the method unmarshal(javax.xml.transform.Source).

Parameters:

pValidating - Whether the Unmarshaller should validate or not.

Throws:

JAXBException - Setting the property failed.

isValidating

boolean isValidating()
                     throws JAXBException

Sets whether the Unmarshaller is validating the objects that it reads. The default is false.

Returns:

True, if the Unmarshaller is validating the objects that it reads, false otherwise.

Throws:

JAXBException - Fetching the property value failed.

See Also:

setValidating(boolean)

setEventHandler

void setEventHandler(ValidationEventHandler pHandler)
                     throws JAXBException

An application may customize the Unmarshallers behaviour in case of validation problems by supplying a custom handler for validation events. The default handler will trigger an exception in case of errors and fatal errors.

Parameters:

pHandler - The custom event handler or null to restore the default event handler.

Throws:

JAXBException - Setting the handler failed.

getEventHandler

ValidationEventHandler getEventHandler()
                                       throws JAXBException

If the JAXB application has registered a custom handler for validation events, returns that handler. Otherwise returns the default handler, which is triggering an exception in case of errors and fatal errors.

Throws:

JAXBException

setProperty

void setProperty(java.lang.String pName,
                 java.lang.Object pValue)
                 throws PropertyException

Sets the unmarshaller property pName to the value pValue. Note, that the value type depends on the property being set.

Parameters:

pName - The property name.

Throws:

PropertyException - An error occurred while processing the property.

java.lang.IllegalArgumentException - The name parameter was null.

getProperty

java.lang.Object getProperty(java.lang.String pName)
                             throws PropertyException

Returnss the unmarshaller property pName to the value pValue. Note, that the value type depends on the property being set.

Parameters:

pName - The property name.

Throws:

PropertyException - An error occurred while processing the property.

java.lang.IllegalArgumentException - The name parameter was null.