$.ajax({

        url : "NameServlet",
        dataType : 'json',
        error : function() {

            alert("Error");
        },
        success : function(data) {
            $.each(data.jsonArray, function(index) {
                var selectBox="<select>"
                  $.each(data.jsonArray[index], function(key, value) {
                    selectBox+="<option>"+key + " & value " + value + "</option>";

                 }); 
                 selectBox+="</select>";
                 // given html id which you want to put it 
                 $("#htmlid").html(selectBox);
            });

        }
});

希望对你有帮助。

您的jsp应该在响应中打印JSON。
JSP文件：

<%
    //obtain the data from a query
    //asuming getClients() return a String in JSON format
    String clients = DB.getClients();

    //this prints de json in the response out
    out.print(clients);
%>

在此之后，您可以在 AJAX 回调中访问包含JSON对象的字符串：
HTML文件（或其他JSP文件）：

<script type="text/javascript">
    //url from your JSP page
    //data contains the output printed previously
    $ajax(url,function(data){
        //it is convenient to clean de output
        var stringData = data.trim();

        //now that you have a json formated String you need to use a parser that
        //converts the String into a JsonObject
        var jsonData = JSON.parse(stringData);

        //take some actions with the data obtained
        var htmlVar = '';
        for (var i=0; i<jsonData.length; i++){
            //add to htmlVar the HTML code for the options 
            htmlVar += '<option value="'+jsonData[i].clientId+'">'+jsonData[i].clientName+'</option>'
        }
        //load the data into the dropDown element
        $('#clientsDropDown').html(htmlVar)
    });
</script>