如何在Spring + JSP中查看发送请求和获取响应之间的时差

Question

I struck in this part of my code.

I am using Spring+Hibernate to fetch records from database and JSP to view those records.

The problem here is it is taking almost 10sec to display 500 records :(

So,I kept some timestamps to see where it is taking moretime.

I found some Interesting things :

1.To go from jsp page to DAO where I have code to fetch records it is taking more time(dont know exatly how much time it is taking)

2.To fetch records from database it is taking milliseconds

3.Do dispaly them back to jsp it is taking 3seconds.

My Question is how to find the time in first case.I successfully find time in remaining two cases.

so,I put Timestamp in JSP

   <c:if test="${currentPage != 1}">
   <a onclick="return displayTimeFunctionP();" class="button" href="pagination.html?  page=${currentpage-1}">  &lt;&lt; Previous </a>
</c:if>

javascript :

function displayTimeFunctionP() {

<% Timestamp t1 = new Timestamp(new Date().getTime());%>
<%System.out.println("Time stamp in onclick() function[previous] :"+t1); %>  

return false(true also I tested);

}

But it is not displaying time in this page and directly goes to next page and then it is displaying time.But,I function is executing because if I give return false it is not going to next page and not displaying anything.

Why it is happening and how to get timestamp from that javascript before going to next page?

Please help....

Answer 1

This block of java code prints the date into the JS function

function displayTimeFunctionP() {
  <% Timestamp t1 = new Timestamp(new Date().getTime());%>
  <%System.out.println("Time stamp in onclick() function[previous] :"+t1); %>  
  return false;
}

Is resolved as:

function displayTimeFunctionP() { 
  return false;
}

And prints into your server system out: Time stamp in onclick() function[previous] 23423424234 Not into your page.

Also after executing the onclick it does the href navigation and changes the page.

To print in the web page you should use out.println (Without System) but if you print the text directly into the JS function it makes a javascript error. And this not stop the navigator to load the next page. You should use javascript "document" or DOM to print the text in someplace.

Answer 2

try this : First in your html or in jsp define like this :

<p id="demo"></p>

And add the following script :

 <script>
    function myFunction() {
      var d = new Date();
      document.getElementById("demo").innerHTML = d ;
    }
</script>

If you want to print milliseconds try

d.getMilliseconds()