Calling java method on a button click?

[vishwanath nadimpally]

Is there a way we can call a java method on clicking a html button using javascrip? Thanks for any help

[Eric Pascarello]

It is called a posting back a form to the server. You can also look into Ajax which is a fancy way to postback to the server.

Eric

[vishwanath nadimpally]

Thanks Eric. But I still can't fix my problem. This is the code I have inside my jsp.

    
            <%
                for (int j = 1; j < sellTransactions.size(); j++) {
                    ArrayList transaction = (ArrayList) sellTransactions.get(j); %>
      <tr class='summaryData' valign="top"<
          <%
              for(int k = 0; k < transaction.size(); k++) {
          %>
          <td NOWRAP class="pageWhite" align="center">
              <font style="font-family: Verdana, Arial, Helvetica, sans-serif"<
              <%=transaction.get(k)%>
                  </font>
              </td>
          <% }
              transactionId = transaction.get(0).toString();
//              System.out.println("-- " + transactionId);
              String url = request.getContextPath() +
                            "/ITHedgeController?" +
                            "TransactionId=" + transactionId +
                            "&TransactionType=SELL" +
                            "&userName=" + request.getParameter("userName") +
                            "&FROM_VIEW=SELL_AREA";
          %>
          <td>
          <a href="<%=url%>">Buy At This Price</a>
              </td>
          <%} %>
          </tr>
 
             <% }  %>
 

I am building a url and using a 'href' to redirect to a servlet which calls a method.

    <a href="<%=url%>">Buy At This Price</a> 

I want to replace this above line with a

    
input type="button" name"Buy At This Price" onclck="some js funciton"

in such a way that I want to skip the call to the servlet and use the js function to determine the click and be able to call my java method directly.

[Bear Bibeault]

You cannot call a java method directly from Javascript. You might find this article an interesting read in order to find out why.

You can use Ajax to go back to the server and call your function from a servlet, or you could use the DWR Toolkit which uses Ajax to perform "direct web remoting" which is a pretty good approximation of an RPC call from JavaScript to server-side Java.

[vishwanath nadimpally]

Originally posted by Bear Bibeault:
You cannot call a java method directly from Javascript. You might find this article an interesting read in order to find out why.

You can use Ajax to go back to the server and call your function from a servlet, or you could use the DWR Toolkit which uses Ajax to perform "direct web remoting" which is a pretty good approximation of an RPC call from JavaScript to server-side Java.

Thanks Bear! Your article is very interesting. I have done a temporary fix, but in the long run I might end up using AJAX for this, because I am using this sort of calls in some places , plus I just bought the "AJAX in Action"

[Orem Hun]

The elegant way is to use AJAX or some tools (GWT) based on AJAX. The other way is to set a hidden input variable, say command, a value in 'JS method' and re-submit. In your JSP, parse the command and call your Java method, and show the page. This is not as neat as AJAX as there is a submit and page refresh.

I'm curious to know what is your temporary fix...