Package org.springframework.web.reactive.result.view.freemarker

Class FreeMarkerView

java.lang.Object

org.springframework.web.reactive.result.view.AbstractView

org.springframework.web.reactive.result.view.AbstractUrlBasedView

org.springframework.web.reactive.result.view.freemarker.FreeMarkerView

All Implemented Interfaces:

Aware, BeanNameAware, InitializingBean, ApplicationContextAware, View

public class FreeMarkerView
extends AbstractUrlBasedView

A View implementation that uses the FreeMarker template engine.

Depends on a single FreeMarkerConfig object such as FreeMarkerConfigurer being accessible in the application context. Alternatively the FreeMarker Configuration can be set directly on this class via setConfiguration(freemarker.template.Configuration).

The url property is the location of the FreeMarker template relative to the FreeMarkerConfigurer's templateLoaderPath.

Note: Spring's FreeMarker support requires FreeMarker 2.3 or higher.

Since:

5.0

Author:

Rossen Stoyanchev, Sam Brannen

Field Summary

Fields

Modifier and Type	Field	Description
static final String	SPRING_MACRO_REQUEST_CONTEXT_ATTRIBUTE	Attribute name of the RequestContext instance in the template model, available to Spring's macros — for example, for creating BindStatus objects.

Fields inherited from class org.springframework.web.reactive.result.view.AbstractView

logger, REQUEST_DATA_VALUE_PROCESSOR_BEAN_NAME

Fields inherited from interface org.springframework.web.reactive.result.view.View

BINDING_CONTEXT_ATTRIBUTE

Constructor Summary

Constructors

Constructor	Description
FreeMarkerView()

Method Summary

Modifier and Type	Method	Description
void	afterPropertiesSet()	Invoked by the containing BeanFactory after it has set all bean properties and satisfied BeanFactoryAware, ApplicationContextAware etc.
protected FreeMarkerConfig	autodetectConfiguration()	Autodetect a FreeMarkerConfig object in the ApplicationContext.
boolean	checkResourceExists(Locale locale)	Check that the FreeMarker template used for this view exists and is valid.
protected freemarker.template.Configuration	getConfiguration()	Get the FreeMarker Configuration used by this view.
protected String	getEncoding()	Get the encoding for the FreeMarker template.
protected reactor.core.publisher.Mono<Map<String,Object>>	getModelAttributes(Map<String,?> model, ServerWebExchange exchange)	Prepare the model to use for rendering by potentially exposing a RequestContext for use in Spring FreeMarker macros and then delegating to the inherited implementation of this method.
protected freemarker.template.ObjectWrapper	getObjectWrapper()	Get the configured FreeMarker ObjectWrapper, or the default wrapper if none specified.
protected freemarker.template.Template	getTemplate(Locale locale)	Deprecated, for removal: This API element is subject to removal in a future version. since 6.1, in favor of lookupTemplate(Locale), to be removed in 6.2
protected freemarker.template.SimpleHash	getTemplateModel(Map<String,Object> model, ServerWebExchange exchange)	Build a FreeMarker template model for the given model map.
protected reactor.core.publisher.Mono<freemarker.template.Template>	lookupTemplate(Locale locale)	Retrieve the FreeMarker template for the given locale, to be rendered by this view.
protected freemarker.template.Configuration	obtainConfiguration()	Obtain the FreeMarker Configuration for actual use.
protected reactor.core.publisher.Mono<Void>	renderInternal(Map<String,Object> renderAttributes, MediaType contentType, ServerWebExchange exchange)	Subclasses must implement this method to actually render the view.
reactor.core.publisher.Mono<Boolean>	resourceExists(Locale locale)	Check that the FreeMarker template used for this view exists and is valid.
void	setConfiguration(freemarker.template.Configuration configuration)	Set the FreeMarker Configuration to be used by this view.
void	setEncoding(String encoding)	Set the encoding of the FreeMarker template file.
void	setExposeSpringMacroHelpers(boolean exposeSpringMacroHelpers)	Set whether to expose a RequestContext for use by Spring's macro library, under the name "springMacroRequestContext".

Methods inherited from class org.springframework.web.reactive.result.view.AbstractUrlBasedView

getUrl, setUrl, toString

Methods inherited from class org.springframework.web.reactive.result.view.AbstractView

createRequestContext, formatViewName, getApplicationContext, getBeanName, getDefaultCharset, getRequestContextAttribute, getRequestDataValueProcessor, getSupportedMediaTypes, obtainApplicationContext, render, resolveAsyncAttributes, setApplicationContext, setBeanName, setDefaultCharset, setRequestContextAttribute, setSupportedMediaTypes

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.springframework.web.reactive.result.view.View

isRedirectView

Field Details

SPRING_MACRO_REQUEST_CONTEXT_ATTRIBUTE

public static final String SPRING_MACRO_REQUEST_CONTEXT_ATTRIBUTE

Attribute name of the RequestContext instance in the template model, available to Spring's macros — for example, for creating BindStatus objects.

Since:

5.2

See Also:

• setExposeSpringMacroHelpers(boolean)
• Constant Field Values

Constructor Details

FreeMarkerView

public FreeMarkerView()

Method Details

setConfiguration

public void setConfiguration(@Nullable
 freemarker.template.Configuration configuration)

Set the FreeMarker Configuration to be used by this view.

Typically this property is not set directly. Instead a single FreeMarkerConfig is expected in the Spring application context which is used to obtain the FreeMarker configuration.

getConfiguration

@Nullable
protected freemarker.template.Configuration getConfiguration()

Get the FreeMarker Configuration used by this view.

obtainConfiguration

protected freemarker.template.Configuration obtainConfiguration()

Obtain the FreeMarker Configuration for actual use.

Returns:

the FreeMarker configuration (never null)

Throws:

IllegalStateException - in case of no Configuration object set

See Also:

• getConfiguration()

setEncoding

public void setEncoding(@Nullable
 String encoding)

Set the encoding of the FreeMarker template file.

By default FreeMarkerConfigurer sets the default encoding in the FreeMarker configuration to "UTF-8". It's recommended to specify the encoding in the FreeMarker Configuration rather than per template if all your templates share a common encoding.

getEncoding

@Nullable
protected String getEncoding()

Get the encoding for the FreeMarker template.

setExposeSpringMacroHelpers

public void setExposeSpringMacroHelpers(boolean exposeSpringMacroHelpers)

Set whether to expose a RequestContext for use by Spring's macro library, under the name "springMacroRequestContext".

Default is true.

Needed for Spring's FreeMarker default macros. Note that this is not required for templates that use HTML forms unless you wish to take advantage of the Spring helper macros.

Since:

5.2

See Also:

• SPRING_MACRO_REQUEST_CONTEXT_ATTRIBUTE

afterPropertiesSet

public void afterPropertiesSet()
                        throws Exception

Description copied from interface: InitializingBean

Invoked by the containing BeanFactory after it has set all bean properties and satisfied BeanFactoryAware, ApplicationContextAware etc.

This method allows the bean instance to perform validation of its overall configuration and final initialization when all bean properties have been set.

Specified by:

afterPropertiesSet in interface InitializingBean

Overrides:

afterPropertiesSet in class AbstractUrlBasedView

Throws:

Exception - in the event of misconfiguration (such as failure to set an essential property) or if initialization fails for any other reason

autodetectConfiguration

protected FreeMarkerConfig autodetectConfiguration()
                                            throws BeansException

Autodetect a FreeMarkerConfig object in the ApplicationContext.

Returns:

the FreeMarkerConfig instance to use for this view

Throws:

BeansException - if no FreeMarkerConfig instance could be found

See Also:

• setConfiguration(freemarker.template.Configuration)

checkResourceExists

public boolean checkResourceExists(Locale locale)
                            throws Exception

Check that the FreeMarker template used for this view exists and is valid.

Can be overridden to customize the behavior, for example in case of multiple templates to be rendered into a single view.

Specified by:

checkResourceExists in class AbstractUrlBasedView

Parameters:

locale - the desired Locale that we're looking for

Returns:

false if the resource exists false if we know that it does not exist

Throws:

Exception - if the resource exists but is invalid (e.g. could not be parsed)

resourceExists

public reactor.core.publisher.Mono<Boolean> resourceExists(Locale locale)

Check that the FreeMarker template used for this view exists and is valid.

Can be overridden to customize the behavior, for example in case of multiple templates to be rendered into a single view.

Overrides:

resourceExists in class AbstractUrlBasedView

Parameters:

locale - the desired Locale that we're looking for

Returns:

false if the resource exists false if we know that it does not exist

Since:

6.1

getModelAttributes

protected reactor.core.publisher.Mono<Map<String,Object>> getModelAttributes(@Nullable
 Map<String,?> model,
 ServerWebExchange exchange)

Prepare the model to use for rendering by potentially exposing a RequestContext for use in Spring FreeMarker macros and then delegating to the inherited implementation of this method.

Overrides:

getModelAttributes in class AbstractView

Since:

5.2

See Also:

• setExposeSpringMacroHelpers(boolean)
• AbstractView.getModelAttributes(Map, ServerWebExchange)

renderInternal

protected reactor.core.publisher.Mono<Void> renderInternal(Map<String,Object> renderAttributes,
 @Nullable
 MediaType contentType,
 ServerWebExchange exchange)

Description copied from class: AbstractView

Subclasses must implement this method to actually render the view.

Specified by:

renderInternal in class AbstractView

Parameters:

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

contentType - the content type selected to render with, which should match one of the supported media types

exchange - current exchange

Returns:

a Mono that represents when and if rendering succeeds

getTemplateModel

protected freemarker.template.SimpleHash getTemplateModel(Map<String,Object> model,
 ServerWebExchange exchange)

Build a FreeMarker template model for the given model map.

The default implementation builds a SimpleHash.

Parameters:

model - the model to use for rendering

exchange - current exchange

Returns:

the FreeMarker template model, as a SimpleHash or subclass thereof

getObjectWrapper

protected freemarker.template.ObjectWrapper getObjectWrapper()

Get the configured FreeMarker ObjectWrapper, or the default wrapper if none specified.

See Also:

• Configurable.getObjectWrapper()

getTemplate

@Deprecated(since="6.1",
            forRemoval=true)
protected freemarker.template.Template getTemplate(Locale locale)
                                            throws IOException

Deprecated, for removal: This API element is subject to removal in a future version.

since 6.1, in favor of lookupTemplate(Locale), to be removed in 6.2

Get the FreeMarker template for the given locale, to be rendered by this view.

By default, the template specified by the "url" bean property will be retrieved.

Parameters:

locale - the current locale

Returns:

the FreeMarker template to render

Throws:

IOException

lookupTemplate

protected reactor.core.publisher.Mono<freemarker.template.Template> lookupTemplate(Locale locale)

Retrieve the FreeMarker template for the given locale, to be rendered by this view.

By default, the template specified by the "url" bean property will be retrieved, and the returned mono will subscribe on the bounded elastic scheduler as template lookups can be blocking operations.

Parameters:

locale - the current locale

Returns:

the FreeMarker template to render

Since:

6.1