json-lib包使用总结

                                        使用 JSON 的方法

 

JSON 即 JavaScript Object Natation ，它是一种轻量级的数据交换格式，非常适合于服务器与 JavaScript 的交互。本文将快速讲解 JSON 格式，并通过代码示例演示如何分别在客户端和服务器端进行 JSON 格式数据的处理。

 

Json 必需的包

commons-httpclient-4.1.1jar
commons-lang-2.5.jar
commons-logging-1.1.1.jar
json-lib-2.4-jdk15.jar
ezmorph-1.0.6.jar
commons-collections-3.2.1.jar

commons-beanutils-1.8.3.jar

以上包可以从

http://commons.apache.org/index.html

http://json-lib.sourceforge.net/

http://ezmorph.sourceforge.net/

http://morph.sourceforge.net/

http://www.docjar.com/

中下载到。

 

测试类一：

 

    import net.sf.json.JSONArray;  
    import net.sf.json.JSONObject;  
      
    public class JSONObjectSample {  
          
        //创建JSONObject对象  
        private static JSONObject createJSONObject(){  
            JSONObject jsonObject = new JSONObject();  
            jsonObject.put("name", "kevin");  
            jsonObject.put("Max.score", new Integer(100));  
            jsonObject.put("Min.score", new Integer(50));  
            jsonObject.put("nickname", "picglet");  
            return jsonObject;  
        }  
        public static void main(String[] args) {  
            JSONObject jsonObject = JSONObjectSample.createJSONObject();  
            //输出jsonobject对象  
            System.out.println("jsonObject==>"+jsonObject);  
              
            //判读输出对象的类型  
            boolean isArray = jsonObject.isArray();  
            boolean isEmpty = jsonObject.isEmpty();  
            boolean isNullObject = jsonObject.isNullObject();  
            System.out.println("isArray:"+isArray+" isEmpty:"+isEmpty+" isNullObject:"+isNullObject);  
              
            //添加属性  
            jsonObject.element("address", "swap lake");  
            System.out.println("添加属性后的对象==>"+jsonObject);  
              
            //返回一个JSONArray对象  
            JSONArray jsonArray = new JSONArray();  
            jsonArray.add(0, "this is a jsonArray value");  
            jsonArray.add(1,"another jsonArray value");  
            jsonObject.element("jsonArray", jsonArray);  
            JSONArray array = jsonObject.getJSONArray("jsonArray");  
            System.out.println("返回一个JSONArray对象："+array);  
            //添加JSONArray后的值  
            //{"name":"kevin","Max.score":100,"Min.score":50,"nickname":"picglet","address":"swap lake",  
            //"jsonArray":["this is a jsonArray value","another jsonArray value"]}  
            System.out.println(jsonObject);  
              
            //根据key返回一个字符串  
            String jsonString = jsonObject.getString("name");  
            System.out.println("jsonString==>"+jsonString);  
        }  
    }  

 

测试类二：

 

   import java.util.ArrayList;  
    import java.util.HashMap;  
    import java.util.List;  
    import java.util.Map;  
      
    import net.sf.json.JSONArray;  
    import net.sf.json.JSONObject;  
      
    public class Json {  
        public static void main(String[] args) {  
            Json j = new Json();  
            j.bean2json();  
        }  
      
        public void arr2json() {  
            boolean[] boolArray = new boolean[] { true, false, true };  
            JSONArray jsonArray = JSONArray.fromObject(boolArray);  
            System.out.println(jsonArray);  
            // prints [true,false,true]  
        }  
      
        public void list2json() {  
            List list = new ArrayList();  
            list.add("first");  
            list.add("second");  
            JSONArray jsonArray = JSONArray.fromObject(list);  
            System.out.println(jsonArray);  
            // prints ["first","second"]  
        }  
      
        public void createJson() {  
            JSONArray jsonArray = JSONArray.fromObject("['json','is','easy']");  
            System.out.println(jsonArray);  
            // prints ["json","is","easy"]  
        }  
      
        public void map2json() {  
            Map<String,String> map = HashMap<String,String>()
            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);  
            // prints  
            // ["name":"json","bool":true,"int":1,"arr":["a","b"],"func":function(i){  
            // return this.arr[i]; }]  
        }  
      
        public void bean2json() {  
            JSONObject jsonObject = JSONObject.fromObject(new MyBean());  
            System.out.println(jsonObject);  
            /* 
             * prints  
             * {"func1":function(i){ return this.options[i]; 
             * },"pojoId":1,"name":"json","func2":function(i){ return 
             * this.options[i]; }} 
             */  
        }  
      
        public void json2bean() {  
            String json = "{name=\"json2\",func1:true,pojoId:1,func2:function(a){ return a; },options:['1','2']}";  
            JSONObject jb = JSONObject.fromString(json);  
            JSONObject.toBean(jb, MyBean.class);  
            System.out.println();  
        }  
        
        public void createAJsonObject(){
             JSONObject jsonObject = new JSONObject();
             jsonObject.element("name", "周星星");
             jsonObject.element("sex", "male");
             jsonObject.element("age", 18);
             jsonObject.element("job", "student");

             System.out.println(jsonObject.get("name"));// 周星星
             System.out.println(jsonObject.get("job"));// student
             System.out.println(jsonObject.getString("sex"));// male
             System.out.println(jsonObject.getInt("age"));// 18
               
             String json = "{name:\"周星星\",sex:\"male\",age:18,job:\"student\"}";

              JSONObject jsonObject = JSONObject.fromObject(json);

              //或者使用 JSONObject jsonObject = (JSONObject) JSONSerializer.toJSON(json);

              System.out.println(jsonObject.get("name"));// 周星星

              System.out.println(jsonObject.get("job"));// student

              System.out.println(jsonObject.getString("sex"));// male

              System.out.println(jsonObject.getInt("age"));// 18
             }

 }  

 

   操作的bean:

 

 

    import net.sf.json.JSONFunction;  
      
    public class MyBean {  
        private String name = "json";  
        private int pojoId = 1;  
        // private char[] options = new char[] { 'a', 'f' };  
        private String func1 = "function(i){ return this.options[i]; }";  
        private JSONFunction func2 = new JSONFunction(new String[] { "i" },  
                "return this.options[i];");  
      
        // getters & setters  
        ......  
    }