org.springframework.web.servlet.view.xslt
Class XsltView

java.lang.Object
  org.springframework.context.support.ApplicationObjectSupport
      org.springframework.web.context.support.WebApplicationObjectSupport
          org.springframework.web.servlet.view.AbstractView
              org.springframework.web.servlet.view.AbstractUrlBasedView
                  org.springframework.web.servlet.view.xslt.XsltView

All Implemented Interfaces:

BeanNameAware, InitializingBean, ApplicationContextAware, ServletContextAware, View

public class XsltView
extends AbstractUrlBasedView

XSLT-driven View that allows for response context to be rendered as the result of an XSLT transformation.

The XSLT Source object is supplied as a parameter in the model and then detected during response rendering. Users can either specify a specific entry in the model via the sourceKey property or have Spring locate the Source object. This class also provides basic conversion of objects into Source implementations. See here for more details.

All model parameters are passed to the XSLT Transformer as parameters. In addition the user can configure output properties to be passed to the Transformer.

Since:

2.0

Author:

Rob Harrop, Juergen Hoeller

Field Summary

Fields inherited from class org.springframework.web.servlet.view.AbstractView

DEFAULT_CONTENT_TYPE

Fields inherited from class org.springframework.context.support.ApplicationObjectSupport

logger

Constructor Summary

XsltView()

Method Summary

protected void	configureIndentation(Transformer transformer) Configure the indentation settings for the supplied Transformer.
protected void	configureResponse(Map model, HttpServletResponse response, Transformer transformer) Configure the supplied HttpServletResponse.
protected void	configureTransformer(Map model, HttpServletResponse response, Transformer transformer) Configure the supplied Transformer instance.
protected Source	convertSource(Object source) Convert the supplied Object into an XSLT Source if the Object type is supported.
protected void	copyModelParameters(Map model, Transformer transformer) Copy all entries from the supplied Map into the parameter set of the supplied Transformer.
protected void	copyOutputProperties(Transformer transformer) Copy the configured output Properties, if any, into the output property set of the supplied Transformer.
protected Result	createResult(HttpServletResponse response) Create the XSLT Result used to render the result of the transformation.
protected Transformer	createTransformer(Templates templates) Create the Transformer instance used to prefer the XSLT transformation.
protected Class[]	getSourceTypes() Return the array of Classes that are supported when converting to an XSLT Source.
protected Source	getStylesheetSource() Get the XSLT Source for the XSLT template under the configured URL.
protected TransformerFactory	getTransformerFactory() Return the TransformerFactory that this XsltView uses.
protected void	initApplicationContext() Initialize this XsltView's TransformerFactory.
protected Source	locateSource(Map model) Locate the Source object in the supplied model, converting objects as required.
protected TransformerFactory	newTransformerFactory(Class transformerFactoryClass) Instantiate a new TransformerFactory for this view.
protected void	renderMergedOutputModel(Map model, HttpServletRequest request, HttpServletResponse response) Subclasses must implement this method to actually render the view.
void	setCacheTemplates(boolean cacheTemplates) Turn on/off the caching of the XSLT Templates instance.
void	setErrorListener(ErrorListener errorListener) Set an implementation of the ErrorListener interface for custom handling of transformation errors and warnings.
void	setIndent(boolean indent) Set whether the XSLT transformer may add additional whitespace when outputting the result tree.
void	setOutputProperties(Properties outputProperties) Set arbitrary transformer output properties to be applied to the stylesheet.
void	setSourceKey(String sourceKey) Set the name of the model attribute that represents the XSLT Source.
void	setTransformerFactoryClass(Class transformerFactoryClass) Specify the XSLT TransformerFactory class to use.
void	setUriResolver(URIResolver uriResolver) Set the URIResolver used in the transform.

Methods inherited from class org.springframework.web.servlet.view.AbstractUrlBasedView

afterPropertiesSet, getUrl, setUrl, toString

Methods inherited from class org.springframework.web.servlet.view.AbstractView

addStaticAttribute, createRequestContext, exposeModelAsRequestAttributes, getAttributesMap, getBeanName, getContentType, getRequestContextAttribute, getStaticAttributes, render, setAttributes, setAttributesCSV, setAttributesMap, setBeanName, setContentType, setRequestContextAttribute

Methods inherited from class org.springframework.web.context.support.WebApplicationObjectSupport

getServletContext, getTempDir, getWebApplicationContext, isContextRequired, setServletContext

Methods inherited from class org.springframework.context.support.ApplicationObjectSupport

getApplicationContext, getMessageSourceAccessor, requiredContextClass, setApplicationContext

Methods inherited from class java.lang.Object

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

Constructor Detail

XsltView

public XsltView()

Method Detail

setTransformerFactoryClass

public void setTransformerFactoryClass(Class transformerFactoryClass)

Specify the XSLT TransformerFactory class to use.

The default constructor of the specified class will be called to build the TransformerFactory for this view.

setSourceKey

public void setSourceKey(String sourceKey)

Set the name of the model attribute that represents the XSLT Source. If not specified, the model map will be searched for a matching value type.

The following source types are supported out of the box: Source, Document, Node, Reader, InputStream and Resource.

See Also:

getSourceTypes(), convertSource(java.lang.Object)

setUriResolver

public void setUriResolver(URIResolver uriResolver)

Set the URIResolver used in the transform.

The URIResolver handles calls to the XSLT document() function.

setErrorListener

public void setErrorListener(ErrorListener errorListener)

Set an implementation of the ErrorListener interface for custom handling of transformation errors and warnings.

If not set, a default SimpleTransformErrorListener is used that simply logs warnings using the logger instance of the view class, and rethrows errors to discontinue the XML transformation.

See Also:

SimpleTransformErrorListener

setIndent

public void setIndent(boolean indent)

Set whether the XSLT transformer may add additional whitespace when outputting the result tree.

Default is true (on); set this to false (off) to not specify an "indent" key, leaving the choice up to the stylesheet.

See Also:

OutputKeys.INDENT

setOutputProperties

public void setOutputProperties(Properties outputProperties)

Set arbitrary transformer output properties to be applied to the stylesheet.

Any values specified here will override defaults that this view sets programmatically.

See Also:

Transformer.setOutputProperty(java.lang.String, java.lang.String)

setCacheTemplates

public void setCacheTemplates(boolean cacheTemplates)

Turn on/off the caching of the XSLT Templates instance.

The default value is "true". Only set this to "false" in development, where caching does not seriously impact performance.

initApplicationContext

protected void initApplicationContext()
                               throws BeansException

Initialize this XsltView's TransformerFactory.

Overrides:

initApplicationContext in class ApplicationObjectSupport

Throws:

ApplicationContextException - in case of initialization errors

BeansException - if thrown by ApplicationContext methods

See Also:

ApplicationObjectSupport.setApplicationContext(org.springframework.context.ApplicationContext)

newTransformerFactory

protected TransformerFactory newTransformerFactory(Class transformerFactoryClass)

Instantiate a new TransformerFactory for this view.

The default implementation simply calls TransformerFactory.newInstance(). If a "transformerFactoryClass" has been specified explicitly, the default constructor of the specified class will be called instead.

Can be overridden in subclasses.

Parameters:

transformerFactoryClass - the specified factory class (if any)

Returns:

the new TransactionFactory instance

See Also:

setTransformerFactoryClass(java.lang.Class), getTransformerFactory()

getTransformerFactory

protected final TransformerFactory getTransformerFactory()

Return the TransformerFactory that this XsltView uses.

Returns:

the TransformerFactory (never null)

renderMergedOutputModel

protected void renderMergedOutputModel(Map model,
                                       HttpServletRequest request,
                                       HttpServletResponse response)
                                throws Exception

Description copied from class: AbstractView

Subclasses must implement this method to actually render the view.

The first step will be preparing the request: In the JSP case, this would mean setting model objects as request attributes. The second step will be the actual rendering of the view, for example including the JSP via a RequestDispatcher.

Specified by:

renderMergedOutputModel in class AbstractView

Parameters:

model - combined output Map (never null), with dynamic values taking precedence over static attributes

request - current HTTP request

response - current HTTP response

Throws:

Exception - if rendering failed

createResult

protected Result createResult(HttpServletResponse response)
                       throws Exception

Create the XSLT Result used to render the result of the transformation.

The default implementation creates a StreamResult wrapping the supplied HttpServletResponse's OutputStream.

Parameters:

response - current HTTP response

Returns:

the XSLT Result to use

Throws:

Exception - if the Result cannot be built

locateSource

protected Source locateSource(Map model)
                       throws Exception

Locate the Source object in the supplied model, converting objects as required. The default implementation first attempts to look under the configured source key, if any, before attempting to locate an object of supported type.

Parameters:

model - the merged model Map

Returns:

the XSLT Source object (or null if none found)

Throws:

Exception - if an error occured during locating the source

See Also:

setSourceKey(java.lang.String), convertSource(java.lang.Object)

getSourceTypes

protected Class[] getSourceTypes()

Return the array of Classes that are supported when converting to an XSLT Source.

Currently supports Source, Document, Node, Reader, InputStream and Resource.

Returns:

the supported source types

convertSource

protected Source convertSource(Object source)
                        throws Exception

Convert the supplied Object into an XSLT Source if the Object type is supported.

Parameters:

source - the original source object

Returns:

the adapted XSLT Source

Throws:

IllegalArgumentException - if the given Object is not of a supported type

Exception

configureTransformer

protected void configureTransformer(Map model,
                                    HttpServletResponse response,
                                    Transformer transformer)

Configure the supplied Transformer instance.

The default implementation copies parameters from the model into the Transformer's parameter set. This implementation also copies the output properties into the Transformer output properties. Indentation properties are set as well.

Parameters:

model - merged output Map (never null)

response - current HTTP response

transformer - the target transformer

See Also:

copyModelParameters(Map, Transformer), copyOutputProperties(Transformer), configureIndentation(Transformer)

configureIndentation

protected final void configureIndentation(Transformer transformer)

Configure the indentation settings for the supplied Transformer.

Parameters:

transformer - the target transformer

Throws:

IllegalArgumentException - if the supplied Transformer is null

See Also:

TransformerUtils.enableIndenting(javax.xml.transform.Transformer), TransformerUtils.disableIndenting(javax.xml.transform.Transformer)

copyOutputProperties

protected final void copyOutputProperties(Transformer transformer)

Copy the configured output Properties, if any, into the output property set of the supplied Transformer.

Parameters:

transformer - the target transformer

copyModelParameters

protected final void copyModelParameters(Map model,
                                         Transformer transformer)

Copy all entries from the supplied Map into the parameter set of the supplied Transformer.

Parameters:

model - merged output Map (never null)

transformer - the target transformer

configureResponse

protected void configureResponse(Map model,
                                 HttpServletResponse response,
                                 Transformer transformer)

Configure the supplied HttpServletResponse.

The default implementation of this method sets the content type and encoding from the "media-type" and "encoding" output properties specified in the Transformer.

Parameters:

model - merged output Map (never null)

response - current HTTP response

transformer - the target transformer

createTransformer

protected Transformer createTransformer(Templates templates)
                                 throws TransformerConfigurationException

Create the Transformer instance used to prefer the XSLT transformation.

The default implementation simply calls Templates.newTransformer(), and configures the Transformer with the custom URIResolver if specified.

Parameters:

templates - the XSLT Templates instance to create a Transformer for

Returns:

the Transformer object

Throws:

TransformerConfigurationException - in case of creation failure

getStylesheetSource

protected Source getStylesheetSource()

Get the XSLT Source for the XSLT template under the configured URL.

Returns:

the Source object