5 Replies Latest reply on Mar 31, 2008 4:07 PM by Sylvain Leroux

    Why is convertRequestParameter protected

    Sylvain Leroux Newbie

      Hi everybody.


      I need to access to a GET request parameter.


      org.jboss.seam.web.Parameters#convertRequestParameter does exactly what I want. But this method is protected.


      So my question: Why is the convertRequestParameter method in org.jboss.seam.web.Parameters protected, whereas in the same time, the convertMultiValueRequestParameter method is public?



      Sylvain.

        • 1. Re: Why is convertRequestParameter protected
          Sylvain Leroux Newbie

          Ok,


          I mis-read the code and thought that the requestParam argument was the name of the parameter. But it's the value.


          protected Object convertRequestParameter(String requestParameter,
                                                   Class type)
          



          So I will use getRequestParameters+convertMultiValueRequestParameter in something like this:


          Map<String,String[]> paramMap = parameters.getRequestParameters();
          int my_value parameters.convertMultiValueRequestParameter(paramMap, "my_param", Integer.class);
          



          Maybe this behavior should be encapsuled in a class?


          SL

          • 2. Re: Why is convertRequestParameter protected
            Pete Muir Master

            Sylvain Leroux wrote on Mar 25, 2008 03:10 PM:


            Maybe this behavior should be encapsuled in a class?



            Huh? It already is, Parameters.

            • 3. Re: Why is convertRequestParameter protected
              Sylvain Leroux Newbie

              I wrote class, but I thought more about a missing method for the Parameters class. Let me explain myself:


              As far as I understand, I need 2 method calls just to retrieve the value of a parameter. Something like parameters.getRequestParameter("my_param", MyClass.class) sounds definitively more natural...


              And if I said that, it was not (only) by laziness: because of those two calls, It's difficult to use the value of a request parameter in an EL expression (like in an action of a jPDL pageflow - that's what I tried to do).



              Sylvain.

              • 4. Re: Why is convertRequestParameter protected
                Pete Muir Master

                We could create getConvertedRequestParameter(String name, Class<?> type) - file a request in JIRA.

                • 5. Re: Why is convertRequestParameter protected
                  Sylvain Leroux Newbie

                  Done: JIRA JBSEAM-2801





                  For now, here's how I resolved this issue by using a custom component in order to access to a request parameter from a jPDL action:


                  /**
                   * Give access to request parameters from EL expressions.
                   * 
                   * @usage
                   * <tt>#{param_helper.getConvertedRequestParameter('paramName', stringClass)}</tt>
                   * 
                   * @author Sylvain Leroux
                   *
                   */
                  @Scope(EVENT)
                  @Name("param_helper")
                  public class ParameterHelper {
                      Map<String, String[]>           requestParameters;
                      org.jboss.seam.web.Parameters     parameters;
                      
                      @Create
                      public void initParameterHelper() {
                       parameters = org.jboss.seam.web.Parameters.instance();
                       requestParameters = parameters.getRequestParameters();
                      }
                      
                      public Object getConvertedRequestParameter(String name, Class<?> type) {
                       return parameters.convertMultiValueRequestParameter(requestParameters, name, type);
                      }
                  
                      public static ParameterHelper instance()
                      {
                         return (ParameterHelper) Component.getInstance(ParameterHelper.class, ScopeType.EVENT);
                      }
                  
                      /**
                       * Give access to <tt>String.class</tt> from an EL expression (which cannot access
                       * <em>static fields</em>).
                       * @return String.class
                       */
                      @Factory(scope=APPLICATION)
                      public Class<String> getStringClass() {
                       return String.class;
                      }
                  
                      /**
                       * Give access to <tt>Integer.class</tt> from an EL expression (which cannot access
                       * <em>static fields</em>).
                       * @return Integer.class
                       */
                      @Factory(scope=APPLICATION)
                      public Class<Integer> getIntegerClass() {
                       return Integer.class;
                      }
                      
                      /* ... other class accessors here ... */
                  }
                  



                  Please note that getStringClass, getIntegerClass, ... are required since, AFAIK, I cannot access static fields from an EL expression. I certainly should have put those methods in a separate (APPLICATION scoped) component.