Servlet+Ajax实现搜索智能提示的案例网上很多,先贴上自己使用的代码。
index.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>smart search</title> <style type="text/css"> .mouseOver { background: #00B2EE; color: white; 200px; } .mouseOut { background: #EDEDED; 200px; } </style> <script type="text/javascript"> var xmlHttp; //获取用户输入的关联信息的函数 function getMoreContens() { //获取用户输入 var content = document.getElementById("keyWords").value; if (content == "") { clearContent(); return; } xmlHttp = createXmlHttp(); //给服务器发送数据 var url = "search?keyword="+encodeURI(content); xmlHttp.open("GET",url,true); xmlHttp.onreadystatechange = //回调函数 function callback() { if(xmlHttp.readyState == 4) { if(xmlHttp.status == 200){ var result = decodeURIComponent(xmlHttp.responseText); var json = eval("("+result+")"); clearContent(json); intelliSense(json); } } }; /* xmlhttp的send是传递参数用的,但是只有在使用post方式提交请求的时候才有用 如下: xmlhttp.open("post",url,true); ... xmlhttp.send("data=data&data2=data2"); 用get的话一般就是: xmlhttp.open("get",url,true); ... xmlhttp.send(null); */ xmlHttp.send(null); } //创建XMLHttpRequest function createXmlHttp() { var xmlHttp; if(window.XMLHttpRequest) { xmlHttp = new XMLHttpRequest(); //兼容某些Mozilla浏览器的响应头,强制设置为text/xml,具体参看:http://www.cnblogs.com/perseverancevictory/p/3690769.html if(xmlHttp.overrideMimeType){ xmlHttp.overrideMimeType("text/xml"); } } //兼容IE else if(window.ActiveXObject) { xmlHttp = new ActiveXObject("Microsoft.XMLHTTP"); if(!xmlHttp) { xmlHttp = new ActiveXObject("Msxml2.XMLHTTP"); } } return xmlHttp; } function clearContent() { var contentTableBody = document.getElementById("content_table_body"); var size = contentTableBody.childNodes.length; for(var i=size-1;i>0;i--) { contentTableBody.removeChild(contentTableBody.childNodes[i]); } } function intelliSense(json) { //获取关联数据的长度 var size = json.length; for(var i=0;i<size;i++) { var nextNode = json[i]; var tr= document.createElement("tr"); var td= document.createElement("td"); tr.setAttribute("border", "0"); tr.setAttribute("bgcolor", "#EDEDED"); td.setAttribute("width", "200px"); td.onmouseover=function() { this.className = 'mouseOver'; } td.onmouseout=function() { this.className = 'mouseOut'; } td.onclick=function() { document.getElementById("keyWords").value=this.innerText; } var text=document.createTextNode(nextNode); td.appendChild(text); tr.appendChild(td); document.getElementById("content_table_body").appendChild(tr); } } </script> </head> <body> <div> <input type="text" name="keyWords" id="keyWords" style="200px; height:20px;" onkeyup="getMoreContens()" onfocus="getMoreContens()" onblur="clearContent()" /> <input type="button" id="button" value="百度一下"> <div id="popDiv"> <table id="content_table"> <tbody id="content_table_body"> </tbody> </table> </div> </div> </body> </html>
web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app id="WebApp_ID" version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> <servlet-mapping> <servlet-name>search</servlet-name> <url-pattern>/search</url-pattern> </servlet-mapping> <servlet> <description>搜索</description> <servlet-name>search</servlet-name> <servlet-class>com.baorant.search.SearchServlet</servlet-class> </servlet> </web-app>
SearchServlet类
package com.baorant.search; import java.io.IOException; import java.net.URLEncoder; import java.util.ArrayList; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.alibaba.fastjson.JSON; public class SearchServlet extends HttpServlet { private static List<String> keyWordList = new ArrayList<String>(); static { // 模拟数据 keyWordList.add("yanwei"); keyWordList.add("yantian"); keyWordList.add("yanpeng"); keyWordList.add("yanweichao"); keyWordList.add("yanweiqi"); keyWordList.add("yanyurong"); keyWordList.add("yanmeirong"); keyWordList.add("yanweichen"); keyWordList.add("电影"); keyWordList.add("电影 66ys"); } private static final long serialVersionUID = 1L; @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { doGet(req, resp); } @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { String keyWord = req.getParameter("keyword"); System.out.println(keyWord); List<String> list = keyWord==null?new ArrayList<String>():getDatas(keyWord); String json = JSON.toJSONString(list); //防止乱码 String encodeJSON = URLEncoder.encode(json,"UTF-8"); resp.getWriter().write(encodeJSON); } public static List<String> getDatas(String keyWord) { List<String> list = new ArrayList<String>(); for (int i = 0; i < keyWordList.size(); i++) { if (keyWordList.get(i).contains(keyWord)) { list.add(keyWordList.get(i)); } } return list; } }
已直接从工程build path导入fastjson-1.2.2.jar,但仍然报错:java.lang.ClassNotFoundException: com.alibaba.fastjson.JSON
解决方法:将之前直接导入的jar包复制放入项目中lib目录下,重新编译,成功!