org.springframework.web.servlet
Interface View

All Known Subinterfaces:
SmartView
All Known Implementing Classes:
AbstractAtomFeedView, AbstractExcelView, AbstractFeedView, AbstractJasperReportsSingleFormatView, AbstractJasperReportsView, AbstractJExcelView, AbstractPdfStamperView, AbstractPdfView, AbstractRssFeedView, AbstractTemplateView, AbstractUrlBasedView, AbstractView, AbstractXsltView, ConfigurableJasperReportsView, FreeMarkerView, InternalResourceView, JasperReportsCsvView, JasperReportsHtmlView, JasperReportsMultiFormatView, JasperReportsPdfView, JasperReportsXlsView, JstlView, MappingJacksonJsonView, MarshallingView, RedirectView, TilesJstlView, TilesView, TilesView, VelocityLayoutView, VelocityToolboxView, VelocityView, XsltView

public interface View

MVC View for a web interaction. Implementations are responsible for rendering content, and exposing the model. A single view exposes multiple model attributes.

This class and the MVC approach associated with it is discussed in Chapter 12 of Expert One-On-One J2EE Design and Development by Rod Johnson (Wrox, 2002).

View implementations may differ widely. An obvious implementation would be JSP-based. Other implementations might be XSLT-based, or use an HTML generation library. This interface is designed to avoid restricting the range of possible implementations.

Views should be beans. They are likely to be instantiated as beans by a ViewResolver. As this interface is stateless, view implementations should be thread-safe.

Author:
Rod Johnson, Arjen Poutsma
See Also:
AbstractView, InternalResourceView

Field Summary
static String PATH_VARIABLES
          Name of the HttpServletRequest attribute that contains a Map with path variables.
static String RESPONSE_STATUS_ATTRIBUTE
          Name of the HttpServletRequest attribute that contains the response status code.
 
Method Summary
 String getContentType()
          Return the content type of the view, if predetermined.
 void render(Map<String,?> model, HttpServletRequest request, HttpServletResponse response)
          Render the view given the specified model.
 

Field Detail

RESPONSE_STATUS_ATTRIBUTE

static final String RESPONSE_STATUS_ATTRIBUTE
Name of the HttpServletRequest attribute that contains the response status code.

Note: This attribute is not required to be supported by all View implementations.


PATH_VARIABLES

static final String PATH_VARIABLES
Name of the HttpServletRequest attribute that contains a Map with path variables. The map consists of String-based URI template variable names as keys and their corresponding Object-based values -- extracted from segments of the URL and type converted.

Note: This attribute is not required to be supported by all View implementations.

Method Detail

getContentType

String getContentType()
Return the content type of the view, if predetermined.

Can be used to check the content type upfront, before the actual rendering process.

Returns:
the content type String (optionally including a character set), or null if not predetermined.

render

void render(Map<String,?> model,
            HttpServletRequest request,
            HttpServletResponse response)
            throws Exception
Render the view given the specified model.

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.

Parameters:
model - Map with name Strings as keys and corresponding model objects as values (Map can also be null in case of empty model)
request - current HTTP request
response - HTTP response we are building
Throws:
Exception - if rendering failed