org.springframework.web.servlet

Class ModelAndView

java.lang.Object

org.springframework.web.servlet.ModelAndView

public class ModelAndView
extends java.lang.Object

Holder for both Model and View in the web MVC framework. Note that these are entirely distinct. This class merely holds both to make it possible for a controller to return both model and view in a single return value.

Represents a model and view returned by a handler, to be resolved by a DispatcherServlet. The view can take the form of a String view name which will need to be resolved by a ViewResolver object; alternatively a View object can be specified directly. The model is a Map, allowing the use of multiple objects keyed by name.

Author:

Rod Johnson, Juergen Hoeller, Rob Harrop

See Also:

DispatcherServlet, ViewResolver, HandlerAdapter.handle(HttpServletRequest, HttpServletResponse, java.lang.Object), Controller.handleRequest(HttpServletRequest, HttpServletResponse)

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	cleared Indicates whether or not this instance has been cleared with a call to clear()
private ModelMap	model Model Map
private java.lang.Object	view View instance or view name String

Constructor Summary

Constructors

Constructor and Description
ModelAndView() Default constructor for bean-style usage: populating bean properties instead of passing in constructor arguments.
ModelAndView(java.lang.String viewName) Convenient constructor when there is no model data to expose.
ModelAndView(java.lang.String viewName, java.util.Map<java.lang.String,?> model) Creates new ModelAndView given a view name and a model.
ModelAndView(java.lang.String viewName, java.lang.String modelName, java.lang.Object modelObject) Convenient constructor to take a single model object.
ModelAndView(View view) Convenient constructor when there is no model data to expose.
ModelAndView(View view, java.util.Map<java.lang.String,?> model) Creates new ModelAndView given a View object and a model.
ModelAndView(View view, java.lang.String modelName, java.lang.Object modelObject) Convenient constructor to take a single model object.

Method Summary

Methods

Modifier and Type	Method and Description
ModelAndView	addAllObjects(java.util.Map<java.lang.String,?> modelMap) Add all attributes contained in the provided Map to the model.
ModelAndView	addObject(java.lang.Object attributeValue) Add an attribute to the model using parameter name generation.
ModelAndView	addObject(java.lang.String attributeName, java.lang.Object attributeValue) Add an attribute to the model.
void	clear() Clear the state of this ModelAndView object.
java.util.Map<java.lang.String,java.lang.Object>	getModel() Return the model map.
protected java.util.Map<java.lang.String,java.lang.Object>	getModelInternal() Return the model map.
ModelMap	getModelMap() Return the underlying ModelMap instance (never null).
View	getView() Return the View object, or null if we are using a view name to be resolved by the DispatcherServlet via a ViewResolver.
java.lang.String	getViewName() Return the view name to be resolved by the DispatcherServlet via a ViewResolver, or null if we are using a View object.
boolean	hasView() Indicate whether or not this ModelAndView has a view, either as a view name or as a direct View instance.
boolean	isEmpty() Return whether this ModelAndView object is empty, i.e.
boolean	isReference() Return whether we use a view reference, i.e.
void	setView(View view) Set a View object for this ModelAndView.
void	setViewName(java.lang.String viewName) Set a view name for this ModelAndView, to be resolved by the DispatcherServlet via a ViewResolver.
java.lang.String	toString() Return diagnostic information about this model and view.
boolean	wasCleared() Return whether this ModelAndView object is empty as a result of a call to clear() i.e.

Methods inherited from class java.lang.Object

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

Field Detail

view

private java.lang.Object view

View instance or view name String

model

private ModelMap model

Model Map

cleared

private boolean cleared

Indicates whether or not this instance has been cleared with a call to clear()

Constructor Detail

ModelAndView

public ModelAndView()

Default constructor for bean-style usage: populating bean properties instead of passing in constructor arguments.

See Also:

setView(View), setViewName(String)

ModelAndView

public ModelAndView(java.lang.String viewName)

Convenient constructor when there is no model data to expose. Can also be used in conjunction with addObject.

Parameters:

viewName - name of the View to render, to be resolved by the DispatcherServlet's ViewResolver

See Also:

addObject(java.lang.String, java.lang.Object)

ModelAndView

public ModelAndView(View view)

Convenient constructor when there is no model data to expose. Can also be used in conjunction with addObject.

Parameters:

view - View object to render

See Also:

addObject(java.lang.String, java.lang.Object)

ModelAndView

public ModelAndView(java.lang.String viewName,
            java.util.Map<java.lang.String,?> model)

Creates new ModelAndView given a view name and a model.

Parameters:

viewName - name of the View to render, to be resolved by the DispatcherServlet's ViewResolver

model - Map of model names (Strings) to model objects (Objects). Model entries may not be null, but the model Map may be null if there is no model data.

ModelAndView

public ModelAndView(View view,
            java.util.Map<java.lang.String,?> model)

Creates new ModelAndView given a View object and a model. Note: the supplied model data is copied into the internal storage of this class. You should not consider to modify the supplied Map after supplying it to this class

Parameters:

view - View object to render

model - Map of model names (Strings) to model objects (Objects). Model entries may not be null, but the model Map may be null if there is no model data.

ModelAndView

public ModelAndView(java.lang.String viewName,
            java.lang.String modelName,
            java.lang.Object modelObject)

Convenient constructor to take a single model object.

Parameters:

viewName - name of the View to render, to be resolved by the DispatcherServlet's ViewResolver

modelName - name of the single entry in the model

modelObject - the single model object

ModelAndView

public ModelAndView(View view,
            java.lang.String modelName,
            java.lang.Object modelObject)

Convenient constructor to take a single model object.

Parameters:

view - View object to render

modelName - name of the single entry in the model

modelObject - the single model object

Method Detail

setViewName

public void setViewName(java.lang.String viewName)

Set a view name for this ModelAndView, to be resolved by the DispatcherServlet via a ViewResolver. Will override any pre-existing view name or View.

getViewName

public java.lang.String getViewName()

Return the view name to be resolved by the DispatcherServlet via a ViewResolver, or null if we are using a View object.

setView

public void setView(View view)

Set a View object for this ModelAndView. Will override any pre-existing view name or View.

getView

public View getView()

Return the View object, or null if we are using a view name to be resolved by the DispatcherServlet via a ViewResolver.

hasView

public boolean hasView()

Indicate whether or not this ModelAndView has a view, either as a view name or as a direct View instance.

isReference

public boolean isReference()

Return whether we use a view reference, i.e. true if the view has been specified via a name to be resolved by the DispatcherServlet via a ViewResolver.

getModelInternal

protected java.util.Map<java.lang.String,java.lang.Object> getModelInternal()

Return the model map. May return null. Called by DispatcherServlet for evaluation of the model.

getModelMap

public ModelMap getModelMap()

Return the underlying ModelMap instance (never null).

getModel

public java.util.Map<java.lang.String,java.lang.Object> getModel()

Return the model map. Never returns null. To be called by application code for modifying the model.

addObject

public ModelAndView addObject(java.lang.String attributeName,
                     java.lang.Object attributeValue)

Add an attribute to the model.

Parameters:

attributeName - name of the object to add to the model

attributeValue - object to add to the model (never null)

See Also:

ModelMap.addAttribute(String, Object), getModelMap()

addObject

public ModelAndView addObject(java.lang.Object attributeValue)

Add an attribute to the model using parameter name generation.

Parameters:

attributeValue - the object to add to the model (never null)

See Also:

ModelMap.addAttribute(Object), getModelMap()

addAllObjects

public ModelAndView addAllObjects(java.util.Map<java.lang.String,?> modelMap)

Add all attributes contained in the provided Map to the model.

Parameters:

modelMap - a Map of attributeName -> attributeValue pairs

See Also:

ModelMap.addAllAttributes(Map), getModelMap()

clear

public void clear()

Clear the state of this ModelAndView object. The object will be empty afterwards.

Can be used to suppress rendering of a given ModelAndView object in the postHandle method of a HandlerInterceptor.

See Also:

isEmpty(), HandlerInterceptor.postHandle(HttpServletRequest, HttpServletResponse, java.lang.Object, org.springframework.web.servlet.ModelAndView)

isEmpty

public boolean isEmpty()

Return whether this ModelAndView object is empty, i.e. whether it does not hold any view and does not contain a model.

wasCleared

public boolean wasCleared()

Return whether this ModelAndView object is empty as a result of a call to clear() i.e. whether it does not hold any view and does not contain a model.

Returns false if any additional state was added to the instance after the call to clear().

See Also:

clear()

toString

public java.lang.String toString()

Return diagnostic information about this model and view.

Overrides:

toString in class java.lang.Object