org.springframework.web.servlet.view.json

Class MappingJackson2JsonView

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.AbstractJackson2View

org.springframework.web.servlet.view.json.MappingJackson2JsonView

All Implemented Interfaces:

Aware, BeanNameAware, ApplicationContextAware, ServletContextAware, View

public class MappingJackson2JsonView
extends AbstractJackson2View

Spring MVC View that renders JSON content by serializing the model for the current request using Jackson 2'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).

The default constructor uses the default configuration provided by Jackson2ObjectMapperBuilder.

Compatible with Jackson 2.1 and higher.

Since:

3.1.2

Author:

Jeremy Grelle, Arjen Poutsma, Rossen Stoyanchev, Juergen Hoeller, Sebastien Deleuze

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_CONTENT_TYPE Default content type: "application/json".
static String	DEFAULT_JSONP_CONTENT_TYPE Default content type for JSONP: "application/javascript".

Fields inherited from class org.springframework.web.servlet.view.json.AbstractJackson2View

updateContentLength

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

logger

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

PATH_VARIABLES, RESPONSE_STATUS_ATTRIBUTE, SELECTED_CONTENT_TYPE

Constructor Summary

Constructors

Constructor and Description
MappingJackson2JsonView() Construct a new MappingJackson2JsonView using default configuration provided by Jackson2ObjectMapperBuilder and setting the content type to application/json.

Method Summary

Modifier and Type	Method and Description
protected Object	filterAndWrapModel(Map<String,Object> model, HttpServletRequest request) Filter and optionally wrap the model in MappingJacksonValue container.
protected Object	filterModel(Map<String,Object> model) Filter out undesired attributes from the given model.
Set<String>	getModelKeys() Return the attributes in the model that should be rendered by this view.
Set<String>	getRenderedAttributes() Deprecated. use getModelKeys() instead
protected boolean	isValidJsonpQueryParam(String value) Validate the jsonp query parameter value.
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	setJsonpParameterNames(Set<String> jsonpParameterNames) Set JSONP request parameter names.
void	setJsonPrefix(String jsonPrefix) Specify a custom prefix to use for this view's JSON output.
void	setModelKey(String modelKey) Set the attribute in the model that should be rendered by this view.
void	setModelKeys(Set<String> modelKeys) Set the attributes in the model that should be rendered by 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
protected void	setResponseContentType(HttpServletRequest request, HttpServletResponse response) Set the content type of the response to the configured content type unless the View.SELECTED_CONTENT_TYPE request attribute is present and set to a concrete media type.
protected void	writePrefix(JsonGenerator generator, Object object) Write a prefix before the main content.
protected void	writeSuffix(JsonGenerator generator, Object object) Write a suffix after the main content.

Methods inherited from class org.springframework.web.servlet.view.json.AbstractJackson2View

getEncoding, getObjectMapper, prepareResponse, renderMergedOutputModel, setDisableCaching, setEncoding, setObjectMapper, setPrettyPrint, setUpdateContentLength, writeContent

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

addStaticAttribute, createMergedOutputModel, createRequestContext, createTemporaryOutputStream, exposeModelAsRequestAttributes, generatesDownloadContent, getAttributesMap, getBeanName, getContentType, getRequestContextAttribute, getRequestToExpose, getStaticAttributes, isExposePathVariables, render, setAttributes, setAttributesCSV, setAttributesMap, setBeanName, setContentType, setExposeContextBeansAsAttributes, setExposedContextBeanNames, 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: "application/json". Overridable through AbstractView.setContentType(java.lang.String).

See Also:

Constant Field Values

DEFAULT_JSONP_CONTENT_TYPE

public static final String DEFAULT_JSONP_CONTENT_TYPE

Default content type for JSONP: "application/javascript".

See Also:

Constant Field Values

Constructor Detail

MappingJackson2JsonView

public MappingJackson2JsonView()

Construct a new MappingJackson2JsonView using default configuration provided by Jackson2ObjectMapperBuilder and setting the content type to application/json.

Method Detail

setJsonPrefix

public void setJsonPrefix(String jsonPrefix)

Specify a custom prefix to use for this view's JSON output. Default is none.

See Also:

setPrefixJson(boolean)

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.

See Also:

setJsonPrefix(java.lang.String)

setModelKey

public void setModelKey(String modelKey)

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

Specified by:

setModelKey in class AbstractJackson2View

setModelKeys

public void setModelKeys(Set<String> modelKeys)

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

getModelKeys

public final Set<String> getModelKeys()

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

setRenderedAttributes

@Deprecated
public void setRenderedAttributes(Set<String> renderedAttributes)

Deprecated. use setModelKeys(Set) instead

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

getRenderedAttributes

@Deprecated
public final Set<String> getRenderedAttributes()

Deprecated. use getModelKeys() instead

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

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 MappingJackson2HttpMessageConverter with an @ResponseBody request-handling method.

Default is false.

setJsonpParameterNames

public void setJsonpParameterNames(Set<String> jsonpParameterNames)

Set JSONP request parameter names. Each time a request has one of those parameters, the resulting JSON will be wrapped into a function named as specified by the JSONP request parameter value.

The parameter names configured by default are "jsonp" and "callback".

Since:

4.1

See Also:

JSONP Wikipedia article

isValidJsonpQueryParam

protected boolean isValidJsonpQueryParam(String value)

Validate the jsonp query parameter value. The default implementation returns true if it consists of digits, letters, or "_" and ".". Invalid parameter values are ignored.

Parameters:

value - the query param value, never null

Since:

4.1.8

filterModel

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

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

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

Specified by:

filterModel in class AbstractJackson2View

Parameters:

model - the model, as passed on to AbstractJackson2View.renderMergedOutputModel(java.util.Map<java.lang.String, java.lang.Object>, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)

Returns:

the value to be rendered

filterAndWrapModel

protected Object filterAndWrapModel(Map<String,Object> model,
                                    HttpServletRequest request)

Description copied from class: AbstractJackson2View

Filter and optionally wrap the model in MappingJacksonValue container.

Overrides:

filterAndWrapModel in class AbstractJackson2View

Parameters:

model - the model, as passed on to AbstractJackson2View.renderMergedOutputModel(java.util.Map<java.lang.String, java.lang.Object>, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)

request - current HTTP request

Returns:

the wrapped or unwrapped value to be rendered

writePrefix

protected void writePrefix(JsonGenerator generator,
                           Object object)
                    throws IOException

Description copied from class: AbstractJackson2View

Write a prefix before the main content.

Overrides:

writePrefix in class AbstractJackson2View

Parameters:

generator - the generator to use for writing content.

object - the object to write to the output message.

Throws:

IOException

writeSuffix

protected void writeSuffix(JsonGenerator generator,
                           Object object)
                    throws IOException

Description copied from class: AbstractJackson2View

Write a suffix after the main content.

Overrides:

writeSuffix in class AbstractJackson2View

Parameters:

generator - the generator to use for writing content.

object - the object to write to the output message.

Throws:

IOException

setResponseContentType

protected void setResponseContentType(HttpServletRequest request,
                                      HttpServletResponse response)

Description copied from class: AbstractView

Set the content type of the response to the configured content type unless the View.SELECTED_CONTENT_TYPE request attribute is present and set to a concrete media type.

Overrides:

setResponseContentType in class AbstractView