json实例
关于json的原理我不再说啦，可以访问我的blog
http://fuchangle.iteye.com/blog/1535377，这篇主要看看json实际的应用，下面上代码
发送数据到servlet
servlet接受数据
servlet在web.xml中的配置
至此整个工程写完啦，下面的例子也在实际中常用
发送数据到servlet
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>JSONpage</title>
<script type="text/javascript">
var xmlHttp;
function createXMLHttpRequest() {
if (window.ActiveXObject) { //(window.ActiveXObject)的作用，用来判断浏览器是否支持ActiveX控件，如果支持ActiveX控件，我们可以利用var xml=new ActiveXObject("Microsoft.XMLHTTP")的形式来创建XMLHTTPRequest对象
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
else if (window.XMLHttpRequest) { //而在IE7及非IE浏览器中可以利用var xml=new XMLHttpRequest()创建XMLHttpRequest对象
xmlHttp = new XMLHttpRequest();
}
}
function doJSON(){
var car = getCarObject();
//将js对象转化成JSON对象的text
var carAsJSON = JSON.stringify(car);
alert(carAsJSON);
var url = "JSONTest1?timpStamp="+ new Date().getTime();
createXMLHttpRequest();
xmlHttp.open("POST",url,true);
xmlHttp.onreadystatechange = handleStateChange;
xmlHttp.send(carAsJSON);
}
//Ajax的回调方法
function handleStateChange(){
if(xmlHttp.readyState == 4){ //相应内容解析完成，可以在客户端调用啦
if(xmlHttp.status ==200){ //交易成功
parseResults();
}
}
}
//具体的回调动作
function parseResults(){
var requestDiv = document.getElementById("serverResponse");
if(requestDiv.hasChildNodes()){
requestDiv.removeChild(requestDiv.childNodes[0]);
}
//xmlHttp.responseText是servlet中返回回来的JSON格式的数据，将它创建成一个js的node对象放到DIV中
var responseText = document.createTextNode(xmlHttp.responseText);
requestDiv.appendChild(responseText);
//将JSON格式的TEXT转化成JSON对象，用eval('('+response+')')
var resultJson = eval('('+xmlHttp.responseText+')');
alert(resultJson);
alert(resultJson.name);
alert(resultJson.make);
alert(resultJson.model);
alert(resultJson.year);
alert(resultJson.color);
}
function Car(make,model,year,color){
this.make = make;
this.model = model;
this.year = year;
this.color = color;
}
function getCarObject(){
return new Car("Dodge", "Coronet R/T", 1968, "yellow")
}
</script>
</head>
<body>
<form action="#">
<input type="button" value="Click here to send JSON data to the server" onclick="doJSON();"/>
</form>
<h2>server response:</h2>
<div id="serverResponse"></div>
</body>
</html>
servlet接受数据
package com.json.servlet;
import java.io.BufferedReader;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.json.JSONObject;
public class JSONTest1 extends HttpServlet{
private static final long serialVersionUID = 1L;
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
System.out.println("----");
String json = readJSONStringFromRequestBody(request);
System.out.println("json = " + json);
JSONObject jsonObject = JSONObject.fromObject(json);
jsonObject.put("name", "benchi");
System.out.println("jsonObject= " + jsonObject.toString());
System.out.println(jsonObject.getInt("year"));
System.out.println(jsonObject.getString("make"));
System.out.println(jsonObject.getString("model"));
System.out.println(jsonObject.getString("color"));
//设置返回的格式是text
response.setContentType("text/plain");
response.getWriter().print(jsonObject);
}
public String readJSONStringFromRequestBody(HttpServletRequest request){
StringBuffer json = new StringBuffer();
String line = null;
try {
BufferedReader reader = request.getReader();
while((line = reader.readLine()) != null){
System.out.println("line= " + line);
json.append(line);
}
} catch (Exception e) {
e.printStackTrace();
}
return json.toString();
}
}
servlet在web.xml中的配置
<servlet> <servlet-name>JSONTest1</servlet-name> <servlet-class>com.json.servlet.JSONTest1</servlet-class> </servlet> <servlet-mapping> <servlet-name>JSONTest1</servlet-name> <url-pattern>/JSONTest1</url-pattern> </servlet-mapping>
至此整个工程写完啦，下面的例子也在实际中常用
package com.mengya.jsonTest;
public class JsonBean1 {
private String col;
private String row;
private String value;
public String getCol() {
return col;
}
public void setCol(String col) {
this.col = col;
}
public String getRow() {
return row;
}
public void setRow(String row) {
this.row = row;
}
public String getValue() {
return value;
}
public void setValue(String value) {
this.value = value;
}
}
package com.mengya.jsonTest;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import org.apache.commons.collections.map.HashedMap;
/**
*
* @author fuchangle
*
*/
public class JsonBanTest {
/**
* @param args
*/
public static void main(String[] args) {
boolean[] boolArray = new boolean[] { true, false, true };
JSONArray jsonArray1 = JSONArray.fromObject(boolArray);
System.out.println(jsonArray1);
List list = new ArrayList();
list.add("first");
list.add("second");
JSONArray jsonArray2 = JSONArray.fromObject(list);
System.out.println(jsonArray2);
JSONArray jsonArray3 = JSONArray.fromObject("['json','is','easy']");
System.out.println(jsonArray3);
Map map = new HashedMap();
map.put("name", "json");
map.put("bool", Boolean.TRUE);
map.put("int", new Integer(1));
map.put("arr", new String[] { "a", "b" });
map.put("func", "function(i){return this.arr[i]}");
JSONObject json = JSONObject.fromObject(map);
System.out.println(json);
JsonBean1 jb = new JsonBean1();
jb.setCol("col1");
jb.setRow("row1");
jb.setValue("123");
JSONObject ja = JSONObject.fromObject(jb);
System.out.println(ja.toString());
List list2 = new ArrayList();
JsonBean1 jb2 = new JsonBean1();
jb2.setCol("col1");
jb2.setRow("row1");
jb2.setValue("123");
list2.add(jb);
list2.add(jb2);
JSONArray jsonArray = JSONArray.fromObject(list2);
System.out.println(jsonArray.toString());
String jsonStr = "{name=\"json\",bool:true,int:1,double:2.2,func:function(a){ return a; },array:[1,2]}";
JSONObject jsonObject = JSONObject.fromObject(jsonStr);
System.out.println(jsonObject);
System.out.println(jsonObject.get("name"));
System.out.println(jsonObject.get("bool"));
System.out.println(jsonObject.get("int"));
System.out.println(jsonObject.get("double"));
System.out.println(jsonObject.get("func"));
System.out.println(jsonObject.get("array"));
String basic = "{name = \"fuchangle\", age = 26, address = \"北京海淀区\"}";
JSONObject jsonObject2 = JSONObject.fromObject(basic);
System.out.println(jsonObject2.get("name"));
System.out.println(jsonObject2.get("age"));
System.out.println(jsonObject2.get("address"));
}
}