I am using of htmlunit library and Firebug addon for firefox and for example fill textbox in google and click search with this code:
public static void main() throws IOException{
WebClient browser;
browser = new WebClient();
HtmlPage page;
page=(HtmlPage) browser.getPage("www.google.com");
HtmlForm form=page.getFormByName("f");

form.getInputByName("q").setValueAttribute("search topic");
page=(HtmlPage) form.getInputByName("btnG").click();
but i have problem with componet like component that we write our mail content in the yahoo that probably use javascript instead of simple textArea
and i want help me that how i can fill this component outomatic with htmlunit library or other thing?