public String saveSearch() throws Exception {
        // TODO Auto-generated method stub
        String s=ServletActionContext.getRequest().getParameter("guo");
        HttpServletResponse response = ServletActionContext.getResponse();   
        PrintWriter out=response.getWriter();
        ServletActionContext.getResponse().getWriter().write("your output String");


        System.out.println(s+"==-");
        return null;
    }

<script type="text/javascript" src="<%=request.getContextPath() %>/common/js/jquery-1.3.2.min.js"></script>
<script type="text/javascript" src="<%=request.getContextPath() %>/common/js/jquery.form.js"></script>

<SCRIPT type="text/javascript">
    
    $(document).ready(function() { 
        var options={ 
                target:'#output1', 
                url:"<%=request.getContextPath() %>/search/saveSearch",
                   beforeSubmit:function(){
                    alert("pre");
                   },
                success: function(data){
                    alert("post");
                   }
        };
        
            $("#searchForm").submit(function() { 
                 $(this).ajaxSubmit(options); 
                 return false;
            }); 
     }); 
    
    </SCRIPT>