I have input field where user can type airport code. When user enter airport code in this field it will make Ajax call to backend and it will return exact match which should be populated when user leave this input field.

Second if user enter location name in this same filed it will make Ajax call to backend and it will return few airport locations as a result. Since this time its not an exact match and it returns few airports based on location name, I want div tag to appear at the bottom of this input field so that use can select appropriate location.

Third if user enter garbage text in input filed it will make Ajax call to backend and it will return no result and I want do display an error massage on page.

I need code to accomplish this in IE and FF.

I dont know Ajax. But I do know JavaScript and JSP. Help!!!!