Package org.springframework.web.bind

Class ServletRequestDataBinder

java.lang.Object
org.springframework.validation.DataBinder
org.springframework.web.bind.WebDataBinder
org.springframework.web.bind.ServletRequestDataBinder
All Implemented Interfaces:
PropertyEditorRegistry, TypeConverter
Direct Known Subclasses:
ExtendedServletRequestDataBinder
public class ServletRequestDataBinder extends WebDataBinder
Special DataBinder to perform data binding from servlet request parameters to JavaBeans, including support for multipart files.

See the DataBinder/WebDataBinder superclasses for customization options, which include specifying allowed/required fields, and registering custom property editors.

Can also be used for manual data binding in custom web controllers: for example, in a plain Controller implementation or in a MultiActionController handler method. Simply instantiate a ServletRequestDataBinder for each binding process, and invoke bind with the current ServletRequest as argument: 

 MyBean myBean = new MyBean();
 // apply binder to custom target object
 ServletRequestDataBinder binder = new ServletRequestDataBinder(myBean);
 // register custom editors, if desired
 binder.registerCustomEditor(...);
 // trigger actual binding of request parameters
 binder.bind(request);
 // optionally evaluate binding errors
 Errors errors = binder.getErrors();
 ...
Author:
Rod Johnson, Juergen Hoeller
See Also:

  • Constructor Details

    • ServletRequestDataBinder

      public ServletRequestDataBinder(@Nullable Object target)
      Create a new ServletRequestDataBinder instance, with default object name.
      Parameters:
      target - the target object to bind onto (or null if the binder is just used to convert a plain parameter value)
      See Also:

    • ServletRequestDataBinder

      public ServletRequestDataBinder(@Nullable Object target, String objectName)
      Create a new ServletRequestDataBinder instance.
      Parameters:
      target - the target object to bind onto (or null if the binder is just used to convert a plain parameter value)
      objectName - the name of the target object

  • Method Details

    • bind

      public void bind(ServletRequest request)
      Bind the parameters of the given request to this binder's target, also binding multipart files in case of a multipart request.

      This call can create field errors, representing basic binding errors like a required field (code "required"), or type mismatch between value and bean property (code "typeMismatch").

      Multipart files are bound via their parameter name, just like normal HTTP parameters: i.e. "uploadedFile" to an "uploadedFile" bean property, invoking a "setUploadedFile" setter method.

      The type of the target property for a multipart file can be MultipartFile, byte[], or String. The latter two receive the contents of the uploaded file; all metadata like original file name, content type, etc are lost in those cases.

      Parameters:
      request - the request with parameters to bind (can be multipart)
      See Also:

    • addBindValues

      protected void addBindValues(MutablePropertyValues mpvs, ServletRequest request)
      Extension point that subclasses can use to add extra bind values for a request. Invoked before WebDataBinder.doBind(MutablePropertyValues). The default implementation is empty.
      Parameters:
      mpvs - the property values that will be used for data binding
      request - the current request

    • closeNoCatch

      public void closeNoCatch() throws ServletRequestBindingException
      Treats errors as fatal.

      Use this method only if it's an error if the input isn't valid. This might be appropriate if all input is from dropdowns, for example.

      Throws:
      ServletRequestBindingException - subclass of ServletException on any binding problem