Java中JSONObject相关操作

 maven项目pom配置：

<dependency>
    <groupId>net.sf.json-lib</groupId>
    <artifactId>json-lib</artifactId>
    <version>2.4</version>
    <classifier>jdk15</classifier>
</dependency>

import net.sf.json.JSONObject;

//报文    
String report="{"SEND_TIME":"20170509235000","AREA_SOURCE":"ZSQD","ACID":"QDA9772","TASK":"W/Z","
                + ""PLAN_SOURCE":"QDNEXTPLAN","ADEP":"ZUUU","ADES":"ZSQD","STOD":"0240","STOA":"0525","
                + ""ETOT":"0240","ELDT":"0525","AIRCRAFT_TYPE":"A320","REGID":"B1648","EXECUTE_DATE":"20170510"}";
//转json对象(反序列化)
JSONObject jsonObject = JSONObject.fromObject(report);  
//强转成PlanReport类
PlanReport hbreport=(PlanReport)JSONObject.toBean(jsonObject,PlanReport.class);

//序列化

jsonObject.toString();

//json合并 相同的字段会被后一个覆盖
JSONObject oldjson1=new JSONObject();

oldjson1.put("name", "zhangsan");

JSONObject oldjson2=new JSONObject();

oldjson2.put("name", "lisi");
oldjson2.put("age", "20");

//合并后的json
JSONObject newjson=new JSONObject();

newjson.putAll(oldjson1);
newjson.putAll(oldjson2);

json对比：

/**
 * 
 * 对比json对象中不同的value
 * 
 */
    public static String compareJson(JSONObject json1, JSONObject json2,String key) {
        String str="";
        @SuppressWarnings("unchecked")
        Iterator<String> i = json1.keys();
        while (i.hasNext()) {
            key =  i.next();
            str+= compareJson(json1.get(key), json2.get(key),key);
        }  
        return str;
    }
    public static String compareJson(Object json1,Object json2,String key) {
        String str ="";
        if (  json1   instanceof   JSONObject ) {
            str=compareJson((JSONObject)  json1  ,(JSONObject)   json2,key);
        }else if (  json1   instanceof   JSONArray  ) {
            compareJson((JSONArray)  json1  ,(JSONArray)   json2,key);
        }else if(json1 instanceof String   ){
            str=compareJson((String)  json1  ,(String)   json2,key);
        }else {
            str=compareJson(json1.toString(), json2.toString(), key);
        }
        return str;
    }
    public static String compareJson(String  str1,String str2,String key) {
        String str="";
        if (!str1.equals(str2)&& str2!=null) {
            //System.out.println("字段更新:"+key+ ",原报文数据:"+ str1 +",新报文数据:"+str2);
            str="字段更新:"+key+ ",原报文数据:"+ str1 +",新报文数据:"+str2+" ";
        }
        return str;
    }
    public static void compareJson(JSONArray json1,JSONArray json2,String key) {
        Iterator<?> i1= json1.iterator();
        Iterator<?> i2= json2.iterator();
        while ( i1.hasNext()) {
            compareJson(i1.next(), i2.next(),key);
        }
    }

json中不同字段对比，可以先转换成类再用反射技术进行对比

//通过反射获取到不同的属性
List<String> textList = Lists.newArrayList();  
String jsonstr="";
                try {  
                    Class<? extends PlanReport> clazz = hbreport.getClass();  
                    Field[] fields = hbreport.getClass().getDeclaredFields();  
                    for (Field field : fields) {  
                        PropertyDescriptor pd = new PropertyDescriptor(field.getName(), clazz);  
                        Method getMethod = pd.getReadMethod();  
                        Object o1 = getMethod.invoke(oldreport);  
                        Object o2 = getMethod.invoke(hbreport);  
                        String s1 = o1 == null ? "" : o1.toString();//避免空指针异常  
                        String s2 = o2 == null ? "" : o2.toString();//避免空指针异常  
                         
                        if (!s1.contains(s2)) {  
                            textList.add("字段新增：" + field.getName() + " 字段值：" + s2 + " ");  
                        }  
                    }  
                } catch (Exception e) {  
                    logger.info("计划日志字段新增反射异常日志打印 [{}]", e);
                    System.out.println(e.getMessage());  
                }  
                for (String object : textList) {  
                    jsonstr+=object;
                }

 JSONArray遍历：转换Iterator（迭代器）进行遍历

String str = "[{name:'a',value:'aa'},{name:'b',value:'bb'},{name:'c',value:'cc'},{name:'d',value:'dd'}]" ;
JSONArray jsonarr = JSONArray.fromObject(str );
Iterator<Object> it = jsonarr.iterator();
while (it.hasNext()) {
    JSONObject jsonObject = (JSONObject) it.next();
    System.out.println(jsonObject.toString());
}

 JSONArray 中按照某个Key排序：

JSONArray JsonArray=new JSONArray();
JsonArray.add(***);
//从小到大
JsonArray.sort(new Comparator<JSONObject>() {
            @Override
            public int compare(JSONObject o1, JSONObject o2) {
                return o1.getString("SEND_TIME").compareTo(o2.getString("SEND_TIME"));
            }
        });