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Extracting and processing textarea value form without changing the page

I have a JSP file in which there are two textareas and a submit button all in a form ;
<form action="" method="post">
<textarea name="inConsole" id="in" cols="100" rows="10"> </textarea> <br/>
<input type="submit" name="Send Command"/> <br/>
<textarea name="outConsole" id="out" cols="100" rows="10"></textarea>
</form>
this page is supposed to work like any SQL program. so the user types a command in the first textarea and clicks submit, then the value of textarea will be extracted to a field and a method will take care of the command and return a log (1 row inserted, error:bad syntax etc) which will be displayed in the second textarea.
I know how for example make a login page and send data and redirect user to a new page(new jsp) file if user pass is correct.
what I can't find is how can I do all the things that I said above without going to a new page while using form action.
I have checked other questions that linked the action attribute to a servlet which was confusing for me( the way that a servlet was called). I'm looking forward to use a simple scriptlet for this purpose like the one I used for my login page:
<%
DatabaseLoginTest dbLogTest = new DatabaseLoginTest();
if (dbLogTest.DBLoginChecker(request.getParameter("user"), request.getParameter("pass")) == true){
%>
<p>Login Successful</p>
<% } else { %>
<p>Login Failed</p>
<% } %>
also I'm aware that adding java scripts(not Javascript scripts:) ) to html isn't a good practice(and the reasons for it) but I think this might be easier for a simple program that I'm working on.
p.s: I'm using tomcat and Intellij for developing this web application
and I have made a custom SQL so I only need the code that gives me the textarea value and the one that sets the other one's value
Update: now I know I should use javascript but I don't know how can I send the data extracted by javascript to a java method.

If you want to do this while remaining in the same page, you have to use Javascript. This is because if you want the server to be able to re-render the page, there has to be a page refresh.
You would need to write onClick handler for the submit button and make a Ajax call to your server to a specific URL with the user input. This URL would serve the data needed for the necessary UI changes.
You can use a scriptlet to generate the HTML that would be shown in the webpage but this would only suffice for a simple use-case and it would be a lot simpler if, say, your service returned just the data required to make the UI change and actual UI change is handled by the JS.
Also,I don't think it is a bad practice to embed JS in HTML. Sure, you can optimize this by including a JS source file but that's a separate optimization.

How to map server response retrieved in jsp to an iFrame

I'm using struts2 framework(java/js/html/css combo) for my webapp. I am reading a text file from server and I want to write the response to an iFrame present in the same jsp.
Flow:
(1) On click of a link, I pass the relative URL of the text file to jsp.
(2) When the jsp page loads, the java code in the jsp reads the file from server.
(3) Now this response has to be written to an iFrame present in the same jsp file
Can anyone plz help me in writing such response to an iFrame?
Thanks in advance :)

[code not tested, only a demostration of the concept]
here's some very rough idea as to how to fix your code, they definitly not the best but they should be enough to help you understand the concept.
However I'd still recommend going over the whole concept and maybe come up with a more efficent way to do what you need.
if you insist on using iframe, you need to make use of 2 seperate jsp as W3C says in "Implementing HTML Frames":
Any frame that attempts to assign as its SRC a URL used by any of its ancestors is treated as if it has no SRC URL at all (basically a blank frame).
so you'll need 2 jsp, the first one is basically what you have but the the src of the iframe changed to:
<iframe scrolling="yes" width="80%" height="200" src="second.jsp?content=<%=all%>" name="imgbox" id="imgbox">
and the second one will be something like :
<html><body><%= request.getAttribute("content") %></body></html>
From the code you've shown you forced a "content update" on the iframe by using javascript. The proper/usual way to update an iframe is to provide different input parameter to the second jsp and let it update it for you.
Finally, I'd recommend using JSTL as much as possible instead of scriptlets. It is much cleaner.

What you need to do is set the src attribute of the IFRAME to the jsp url when your link is clicked. Another way to do it is doing something like this:
<iframe src="" name="iframe_a"></iframe>
<p>W3Schools.com</p>
with the correct parameters of course

Jsoup href with function jscript

Guys I'm using the JSoup library to extract some data from a html page, but now I'm needing to jump to the next page, and this link on the next line.
<a class="jsEnabled nextBtn cursorPointer" href="javascript:setSelectedLink('NextPageButton');" title="Next page" alt="Next page"></a>
Ie, he is in a jscript function, how do I do to get the link dynamically?

Unfortunately jsoup can't execute javascripts. But you can use other libraries, eg. HtmlUnit do do so.
Did you check if the website has some plain html alternatives in, which allow you to get to the next page?

call java function from JSP page's button on click event

There is an application that stores photos in oracle db (oracle multimedia format). There is a JAVA servlet page that handle the connection and the SQLs ..., and there are JSP pages to show the images in browser.
There is a delete function in the JAVA page, when i click one thumbnail it navigates to the an other JSP and show the full size image. Here i would like to call the
public void deleteRowById( String selectId ) function which is in the JAVA servlet page. i would like to use a button, and i'm not realy know what is the proper way to call this function.
Any suggestions are welcome.

In the mean time i solved the situation. There is a java class that contains SQL statements -taht's what i would like to call with a form button.
1st JSP page show the button like delete, it navigates to an other JSP page via passing a parameter with post method, in this 2nd JSP page i call the main java class method that execute a delete statement then from the 2nd JSP page i navigate back with <jsp:forward page="1st_page.jsp"/>
Maybe not a cutting edge solution but works like charm :)

Calling JSF ManageBean after PageLoad using f:event postAddToView

I am writing an app using JSF 2.0.
For one of the page, there is a section of the page that takes a long time to display.
To improve the user experience, I am thinking to load the page first and then automatically do an Ajax call back to the JSF manage bean object once the page is loaded successfully after 1st load.
I am thinking to use f:event with type postAddView.
<h:outputText id="dummyId">
<f:event type="postAddToView" listener="#{mngBean.doSomething}" />
</h:outputText>
However it seems like f:event postAddToView is still being processed before the page is displayed for the first time.
The other options that I have explore is to create a hidden button and get javascript to trigger it. It works however I am just wondering if there is a nice JSF component/event that can do this instead of using java script.
Thanks for your help.
<h:commandButton id="dmyButton"
value="#{mngBean.getSomething}"
actionListener="#{mngBean.doSomething}"
style="display: none"
type="submit">
Java Script
<script language="JavaScript">
$(document).ready(function() {
if (document.getElementById('form:dmyButton').value == 'true') {
document.getElementById('form:dmyButton').click();
}
});
</script>
Thanks for all your help in advance

I think the PreRenderViewEvent is what you want.
http://javaserverfaces.java.net/nonav/docs/2.0/javadocs/javax/faces/event/PreRenderViewEvent.html
Though the docs don't show it, the preRenderViewEvent does work with f:event. I'll fix the docs presently.

PostAddToViewEvent is processed "During Restore View Phase, after a
component has been added to a view." (according to Java Server Faces 2.0 - The Complete Reference) which means it is really early in the lifecycle (Restore View is the first lifecycle phase).
I don't think that any PhaseListener will help you in this case, since they all run on the server side, not on the client side.
However, <f:ajax> can be applied to <h:body>, with event="load". I tried it, but it didn't really work, <f:ajax> wrapping <h:body> nothing happened, the other way around I got Unable to attach <f:ajax> to non-ClientBehaviorHolder parent error.