org.springframework.web.servlet.view.json
Class MappingJacksonJsonView

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.json.MappingJacksonJsonView

All Implemented Interfaces:

Aware, BeanNameAware, ApplicationContextAware, ServletContextAware, View

public class MappingJacksonJsonView
extends AbstractView

Spring-MVC View that renders JSON content by serializing the model for the current request using Jackson's ObjectMapper.

By default, the entire contents of the model map (with the exception of framework-specific classes) will be encoded as JSON. If the model contains only one key, you can have it extracted encoded as JSON alone via setExtractValueFromSingleKeyModel(boolean). Or you can select specific model attributes to be encoded as JSON via ... TODO

Since:

3.0

Author:

Jeremy Grelle, Arjen Poutsma, Rossen Stoyanchev

See Also:

MappingJacksonHttpMessageConverter

Field Summary

static String

DEFAULT_CONTENT_TYPE Default content type.

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

logger

Fields inherited from interface org.springframework.web.servlet.View

PATH_VARIABLES, RESPONSE_STATUS_ATTRIBUTE

Constructor Summary

MappingJacksonJsonView()
Construct a new JacksonJsonView, setting the content type to application/json.

Method Summary

protected Object	filterModel(Map<String,Object> model) Filters out undesired attributes from the given model.
Set<String>	getModelKeys() Returns the attributes in the model that should be rendered by this view.
Set<String>	getRenderedAttributes() Deprecated. use getModelKeys() instead
protected void	prepareResponse(HttpServletRequest request, HttpServletResponse response) Prepare the given response for rendering.
protected void	renderMergedOutputModel(Map<String,Object> model, HttpServletRequest request, HttpServletResponse response) Subclasses must implement this method to actually render the view.
void	setDisableCaching(boolean disableCaching) Disables caching of the generated JSON.
void	setEncoding(org.codehaus.jackson.JsonEncoding encoding) Sets the JsonEncoding for this converter.
void	setExtractValueFromSingleKeyModel(boolean extractValueFromSingleKeyModel) Set whether to serialize models containing a single attribute as a map or whether to extract the single value from the model and serialize it directly.
void	setModelKey(String modelKey) Sets the attribute in the model that should be rendered by this view.
void	setModelKeys(Set<String> modelKeys) Sets the attributes in the model that should be rendered by this view.
void	setObjectMapper(org.codehaus.jackson.map.ObjectMapper objectMapper) Sets the ObjectMapper for this view.
void	setPrefixJson(boolean prefixJson) Indicates whether the JSON output by this view should be prefixed with "{} && ".
void	setRenderedAttributes(Set<String> renderedAttributes) Deprecated. use setModelKeys(Set) instead

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

addStaticAttribute, createMergedOutputModel, createRequestContext, createTemporaryOutputStream, exposeModelAsRequestAttributes, generatesDownloadContent, getAttributesMap, getBeanName, getContentType, getRequestContextAttribute, getStaticAttributes, isExposePathVariables, render, setAttributes, setAttributesCSV, setAttributesMap, setBeanName, setContentType, setExposePathVariables, setRequestContextAttribute, toString, writeToResponse

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

getServletContext, getTempDir, getWebApplicationContext, initApplicationContext, initServletContext, isContextRequired, setServletContext

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

getApplicationContext, getMessageSourceAccessor, initApplicationContext, requiredContextClass, setApplicationContext

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_CONTENT_TYPE

public static final String DEFAULT_CONTENT_TYPE

Default content type. Overridable as bean property.

See Also:

Constant Field Values

Constructor Detail

MappingJacksonJsonView

public MappingJacksonJsonView()

Construct a new JacksonJsonView, setting the content type to application/json.

Method Detail

setObjectMapper

public void setObjectMapper(org.codehaus.jackson.map.ObjectMapper objectMapper)

Sets the ObjectMapper for this view. If not set, a default ObjectMapper is used.

Setting a custom-configured ObjectMapper is one way to take further control of the JSON serialization process. For example, an extended SerializerFactory can be configured that provides custom serializers for specific types. The other option for refining the serialization process is to use Jackson's provided annotations on the types to be serialized, in which case a custom-configured ObjectMapper is unnecessary.

setEncoding

public void setEncoding(org.codehaus.jackson.JsonEncoding encoding)

Sets the JsonEncoding for this converter. By default, UTF-8 is used.

setPrefixJson

public void setPrefixJson(boolean prefixJson)

Indicates whether the JSON output by this view should be prefixed with "{} && ". Default is false.

Prefixing the JSON string in this manner is used to help prevent JSON Hijacking. The prefix renders the string syntactically invalid as a script so that it cannot be hijacked. This prefix does not affect the evaluation of JSON, but if JSON validation is performed on the string, the prefix would need to be ignored.

setModelKey

public void setModelKey(String modelKey)

Sets the attribute in the model that should be rendered by this view. When set, all other model attributes will be ignored.

setModelKeys

public void setModelKeys(Set<String> modelKeys)

Sets the attributes in the model that should be rendered by this view. When set, all other model attributes will be ignored.

getModelKeys

public Set<String> getModelKeys()

Returns the attributes in the model that should be rendered by this view.

setRenderedAttributes

public void setRenderedAttributes(Set<String> renderedAttributes)

Deprecated. use setModelKeys(Set) instead

Sets the attributes in the model that should be rendered by this view. When set, all other model attributes will be ignored.

getRenderedAttributes

public Set<String> getRenderedAttributes()

Deprecated. use getModelKeys() instead

Returns the attributes in the model that should be rendered by this view.

setDisableCaching

public void setDisableCaching(boolean disableCaching)

Disables caching of the generated JSON.

Default is true, which will prevent the client from caching the generated JSON.

setExtractValueFromSingleKeyModel

public void setExtractValueFromSingleKeyModel(boolean extractValueFromSingleKeyModel)

Set whether to serialize models containing a single attribute as a map or whether to extract the single value from the model and serialize it directly. The effect of setting this flag is similar to using MappingJacksonHttpMessageConverter with an @ResponseBody. request-handling method.

Default is false.

prepareResponse

protected void prepareResponse(HttpServletRequest request,
                               HttpServletResponse response)

Description copied from class: AbstractView

Prepare the given response for rendering.

The default implementation applies a workaround for an IE bug when sending download content via HTTPS.

Overrides:

prepareResponse in class AbstractView

Parameters:

request - current HTTP request

response - current HTTP response

renderMergedOutputModel

protected void renderMergedOutputModel(Map<String,Object> 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

filterModel

protected Object filterModel(Map<String,Object> model)

Filters out undesired attributes from the given model. The return value can be either another Map, or a single value object.

Default implementation removes BindingResult instances and entries not included in the renderedAttributes property.

Parameters:

model - the model, as passed on to renderMergedOutputModel(java.util.Map, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)

Returns:

the object to be rendered