public class MappingJacksonJsonView extends AbstractView
View
that renders JSON content by serializing the model for the current request
using Jackson 1.x'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)
.
Modifier and Type | Field and Description |
---|---|
static java.lang.String |
DEFAULT_CONTENT_TYPE
Default content type: "application/json".
|
private boolean |
disableCaching |
private JsonEncoding |
encoding |
private boolean |
extractValueFromSingleKeyModel |
private java.lang.String |
jsonPrefix |
private java.util.Set<java.lang.String> |
modelKeys |
private ObjectMapper |
objectMapper |
private java.lang.Boolean |
prettyPrint |
private boolean |
updateContentLength |
logger
PATH_VARIABLES, RESPONSE_STATUS_ATTRIBUTE, SELECTED_CONTENT_TYPE
Constructor and Description |
---|
MappingJacksonJsonView()
Construct a new
MappingJacksonJsonView , setting the content type to application/json . |
Modifier and Type | Method and Description |
---|---|
private void |
configurePrettyPrint() |
protected java.lang.Object |
filterModel(java.util.Map<java.lang.String,java.lang.Object> model)
Filter out undesired attributes from the given model.
|
JsonEncoding |
getEncoding()
Return the
JsonEncoding for this view. |
java.util.Set<java.lang.String> |
getModelKeys()
Return the attributes in the model that should be rendered by this view.
|
ObjectMapper |
getObjectMapper()
Return the
ObjectMapper for this view. |
java.util.Set<java.lang.String> |
getRenderedAttributes()
Deprecated.
use
getModelKeys() instead |
protected void |
prepareResponse(HttpServletRequest request,
HttpServletResponse response)
Prepare the given response for rendering.
|
protected void |
renderMergedOutputModel(java.util.Map<java.lang.String,java.lang.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(JsonEncoding encoding)
Set the
JsonEncoding for this view. |
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 |
setJsonPrefix(java.lang.String jsonPrefix)
Specify a custom prefix to use for this view's JSON output.
|
void |
setModelKey(java.lang.String modelKey)
Set the attribute in the model that should be rendered by this view.
|
void |
setModelKeys(java.util.Set<java.lang.String> modelKeys)
Set the attributes in the model that should be rendered by this view.
|
void |
setObjectMapper(ObjectMapper objectMapper)
Set the
ObjectMapper for this view. |
void |
setPrefixJson(boolean prefixJson)
Indicates whether the JSON output by this view should be prefixed with "{} && ".
|
void |
setPrettyPrint(boolean prettyPrint)
Whether to use the default pretty printer when writing JSON.
|
void |
setRenderedAttributes(java.util.Set<java.lang.String> renderedAttributes)
Deprecated.
use
setModelKeys(Set) instead |
void |
setUpdateContentLength(boolean updateContentLength)
Whether to update the 'Content-Length' header of the response.
|
protected void |
writeContent(java.io.OutputStream stream,
java.lang.Object value,
java.lang.String jsonPrefix)
Write the actual JSON content to the stream.
|
addStaticAttribute, createMergedOutputModel, createRequestContext, createTemporaryOutputStream, exposeModelAsRequestAttributes, generatesDownloadContent, getAttributesMap, getBeanName, getContentType, getRequestContextAttribute, getStaticAttributes, isExposePathVariables, render, setAttributes, setAttributesCSV, setAttributesMap, setBeanName, setContentType, setExposePathVariables, setRequestContextAttribute, setResponseContentType, toString, writeToResponse
getServletContext, getTempDir, getWebApplicationContext, initApplicationContext, initServletContext, isContextRequired, setServletContext
getApplicationContext, getMessageSourceAccessor, initApplicationContext, requiredContextClass, setApplicationContext
public static final java.lang.String DEFAULT_CONTENT_TYPE
AbstractView.setContentType(java.lang.String)
.private ObjectMapper objectMapper
private JsonEncoding encoding
private java.lang.String jsonPrefix
private java.lang.Boolean prettyPrint
private java.util.Set<java.lang.String> modelKeys
private boolean extractValueFromSingleKeyModel
private boolean disableCaching
private boolean updateContentLength
public MappingJacksonJsonView()
MappingJacksonJsonView
, setting the content type to application/json
.public void setObjectMapper(ObjectMapper objectMapper)
ObjectMapper
for this view.
If not set, a default ObjectMapper
will be used.
Setting a custom-configured ObjectMapper
is one way to take further control of
the JSON serialization process. The other option is to use Jackson's provided annotations
on the types to be serialized, in which case a custom-configured ObjectMapper is unnecessary.
public final ObjectMapper getObjectMapper()
ObjectMapper
for this view.public void setEncoding(JsonEncoding encoding)
JsonEncoding
for this view.
By default, UTF-8 is used.public final JsonEncoding getEncoding()
JsonEncoding
for this view.public void setJsonPrefix(java.lang.String jsonPrefix)
setPrefixJson(boolean)
public void setPrefixJson(boolean prefixJson)
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.
setJsonPrefix(java.lang.String)
public void setPrettyPrint(boolean prettyPrint)
ObjectMapper
as follows:
ObjectMapper mapper = new ObjectMapper(); mapper.configure(SerializationConfig.Feature.INDENT_OUTPUT, true);
The default value is false
.
private void configurePrettyPrint()
public void setModelKey(java.lang.String modelKey)
public void setModelKeys(java.util.Set<java.lang.String> modelKeys)
public final java.util.Set<java.lang.String> getModelKeys()
@Deprecated public void setRenderedAttributes(java.util.Set<java.lang.String> renderedAttributes)
setModelKeys(Set)
instead@Deprecated public final java.util.Set<java.lang.String> getRenderedAttributes()
getModelKeys()
insteadpublic void setExtractValueFromSingleKeyModel(boolean extractValueFromSingleKeyModel)
The effect of setting this flag is similar to using MappingJacksonHttpMessageConverter
with an @ResponseBody
request-handling method.
Default is false
.
public void setDisableCaching(boolean disableCaching)
Default is true
, which will prevent the client from caching the generated JSON.
public void setUpdateContentLength(boolean updateContentLength)
true
, the response is buffered in order to determine the content
length and set the 'Content-Length' header of the response.
The default setting is false
.
protected void prepareResponse(HttpServletRequest request, HttpServletResponse response)
AbstractView
The default implementation applies a workaround for an IE bug when sending download content via HTTPS.
prepareResponse
in class AbstractView
request
- current HTTP requestresponse
- current HTTP responseprotected void renderMergedOutputModel(java.util.Map<java.lang.String,java.lang.Object> model, HttpServletRequest request, HttpServletResponse response) throws java.lang.Exception
AbstractView
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.
renderMergedOutputModel
in class AbstractView
model
- combined output Map (never null
),
with dynamic values taking precedence over static attributesrequest
- current HTTP requestresponse
- current HTTP responsejava.lang.Exception
- if rendering failedprotected java.lang.Object filterModel(java.util.Map<java.lang.String,java.lang.Object> model)
Map
or a single value object.
The default implementation removes BindingResult
instances and entries
not included in the renderedAttributes
property.
model
- the model, as passed on to renderMergedOutputModel(java.util.Map<java.lang.String, java.lang.Object>, HttpServletRequest, HttpServletResponse)
protected void writeContent(java.io.OutputStream stream, java.lang.Object value, java.lang.String jsonPrefix) throws java.io.IOException
stream
- the output stream to usevalue
- the value to be rendered, as returned from filterModel(java.util.Map<java.lang.String, java.lang.Object>)
jsonPrefix
- the prefix for this view's JSON output
(as indicated through setJsonPrefix(java.lang.String)
/setPrefixJson(boolean)
)java.io.IOException
- if writing failed