servlet achieve a similar target = "_ top" feature

　　By many online solutions, most of them are redirected, or jump page, but I have not tried out the original frame, later found to achieve the specified frame to jump from servlet frameset can directly target form form , which do not have to deal with the trouble of the servlet

 1 <form action="${pageContext.request.contextPath}/MessageServlet method=search" target="mainFrame" method="post" id="formid">
 2     <input type="text" name="content" id="content" /> 
 3     <a href="#" target="topFrame" id="sub" onclick="searchTopic()">提交</a>
 4 </form>
 5 
 6 <script type="text/javascript">
 7  function searchTopic()
 8  {
 9   document.getElementById("formid").submit();
10  }
11 </script>