Need to perform an insert operation with AJAX

[PavanPL KalyanK]

Hello please help

I have a textarea on to the jsp page where user can enter a comment , i am using AJAX to submit the data .

I am taking this data inside send method of the XMLHttpRequest.

int a = preparedstatement.executeUpdate(insert query);

My question is that , after performing the operation , how can i inform the status of the insert to the user .


Please guide me with your valuable suggestions.

[K West]

When the property readyState is 4 that means the response is complete and we can get our data.

// Create a function that will receive data sent from the server
ajaxRequest.onreadystatechange = function(){
	if(ajaxRequest.readyState == 4){
		// Get the data from the server's response
	}
}

[PavanPL KalyanK]

Hello West ,

In the DAO implementation class , i am using

int a = preparedstatement.executeUpdate(insert query);

This may either insert successfully or may also , so how do i capture the status ??

[Eric Pascarello]

You need to return something back in the Ajax call that says if it was a success or failure. It is up to you how you return it back and get the result as K West pointed out.

Eric

[PavanPL KalyanK]

hey Eric ,

This was the response i was looking for till now .

As you said " It is up to you how you return it back and get the result"

what do you suggest me to do here ?

Can you please give me an idea how to construct a return type and depend on what conditions .

[Bear Bibeault]

Returning a JSON response with data seems to be called for.

That data can be as simple as true or false (success or failure), or a complex construct that contains severities and messages. Depends upon your needs.

[PavanPL KalyanK]

I am planning to implement in this way :

Declare a string str ;

If an insert fails under the catch block

catch(SQLException e)
{
str = "error";
}

else
str = "success";
return str; 

Am i going in a right way ?

[PavanPL KalyanK]

Bear Bibeault wrote:Returning a JSON response with data seems to be called for.

That data can be as simple as true or false (success or failure), or a complex construct that contains severities and messages. Depends upon your needs.

Can you please point to a link or give an idea of how to achieve this ?

[Eric Pascarello]

JSON is a good place to start

Eric

[K West]

catch(SQLException e)   
{   
str = "error";   
}   
  
else  
str = "success";   
return str; 

Is this in your jsp?

If so, you have to just send this back to ajax call by

<%=str%>

or

response.getWriter().write(str);

at end of your jsp page.

And then get it in ajax response

var resp = xmlHttp.responseText;

And then check weather the resp is sucess or error.

[PavanPL KalyanK]

Eric Pascarello wrote:JSON is a good place to start

Eric

JSON inside DAO implementation class ??

[Bear Bibeault]

PavanPL KalyanK wrote:JSON inside DAO implementation class ??

If your DAOs are in the business of generating a response, then you are definitely doing it wrong.

When a business operation returns its result status, it is the job of the presentation layer to create a response. That response can be a JSON-formatted construct that's easy to consume (much easier than XML) in JavaScript.

If you are doing Ajax "by hand", you're just making things hard on yourself. You should be using a library such as jQuery (or other of your choice) which makes Ajax, and evaluating JSON responses, easy as pie.

[PavanPL KalyanK]

Bear thanks ,