path学习笔记二_H5之家 - 中国HTML5教程资源分享第一站

Json-smart

该篇主要以代码示例为主，因为google上不去，看不到Json-smart这个官方文档和API。故只例举一些代码示例。因为接下来的Json-path底层默认使用的就是JsonSmart。JsonSmart的源码并不多，有兴趣可以去看看

解析简单json格式的字符串 import net.minidev.json.JSONArray; import net.minidev.json.JSONObject; import net.minidev.json.JSONValue; public class ParseJsonString { public static void main(String[] args) { /** * <pre> * [ * 0, * { * '1': { * '2': { * '3': { * '4': [ * 5, * { * '6': 7 * } * ] * } * } * } * } * ] * </pre> * */ String str="[0,{'1':{'2':{'3':{'4':[5,{'6':7}]}}}}]"; if (JSONValue.isValidJson(str)) { //判断是否是合法的json字符串 Object obj=JSONValue.parse(str); JSONArray array=(JSONArray)obj; System.out.println(array.size()); System.out.println(array); JSONObject jsonObject = (JSONObject) array.get(1); System.out.println(jsonObject); JSONObject jsonObject1 = (JSONObject) jsonObject.get("1"); System.out.println(jsonObject1.toJSONString()); JSONObject jsonObject2 = (JSONObject) jsonObject1.get("2"); System.out.println(jsonObject2.toJSONString()); JSONObject jsonObject3 = (JSONObject) jsonObject2.get("3"); System.out.println(jsonObject3.toJSONString()); JSONArray array2 = (JSONArray) jsonObject3.get("4"); System.out.println(array2); JSONObject jsonObject4 = (JSONObject) array2.get(1); System.out.println(jsonObject4.toJSONString()); int data = Integer.parseInt(jsonObject4.get("6").toString()); System.out.println(data); } } }

输出：

2 [0,{"1":{"2":{"3":{"4":[5,{"6":7}]}}}}] {"1":{"2":{"3":{"4":[5,{"6":7}]}}}} {"2":{"3":{"4":[5,{"6":7}]}}} {"3":{"4":[5,{"6":7}]}} {"4":[5,{"6":7}]} [5,{"6":7}] {"6":7} 7 JSONValue的使用 import java.io.IOException; import java.util.HashMap; import java.util.Map; import net.minidev.json.JSONObject; import net.minidev.json.JSONStyle; import net.minidev.json.JSONValue; import net.minidev.json.parser.ParseException; public class JsonValueTest { public static void main(String[] args) throws ParseException, IOException { // public class JSONObject extends HashMap<String, Object> // implements JSONAware, JSONAwareEx, JSONStreamAwareEx {} JSONObject obj = new JSONObject(); obj.put("name", "foo"); obj.put("num", 100); obj.put("balance", 1000.21); obj.put("is_vip", true); obj.put("is_special_fuhao", "'"); obj.put("nickname", null); // 判断是否是合法的json串 System.out.println(JSONValue.isValidJson(obj.toJSONString())); // 转义 quotes, \, /, \r, \n, \b, \f, \t and other control characters (U+0000 through U+001F). System.out.println(JSONValue.escape(obj.toJSONString())); System.out.println(obj.toJSONString()); System.out.println(JSONValue.toJSONString(obj)); // JSONStyle object configure JSonSerializer reducing output size System.out.println(obj.toJSONString(JSONStyle.NO_COMPRESS)); System.out.println(obj.toJSONString(JSONStyle.MAX_COMPRESS)); System.out.println(JSONValue.toJSONString(obj, JSONStyle.MAX_COMPRESS)); System.out.println(JSONValue.compress(obj.toJSONString())); System.out.println(JSONValue.uncompress(obj.toJSONString())); System.out.println(JSONValue.uncompress(JSONValue.toJSONString(obj, JSONStyle.MAX_COMPRESS))); // Parse Json input to a java Object keeping element order System.out.println(JSONValue.parseKeepingOrder(obj.toJSONString())); // 解析字符串的时候会抛异常 throw ParseException System.out.println(JSONValue.parseWithException(obj.toJSONString())); System.out.println("**********************************"); String str="{\"key\":\"Value\"}"; Object obj1=JSONValue.parse(str); System.out.println(obj1); obj1=JSONValue.parseStrict(str); System.out.println(obj1); JSONObject obj2=(JSONObject)obj1; System.out.println(obj2.get("key")); System.out.println("**********************************"); StringBuffer strBuffer = new StringBuffer("zhangsan"); Map<String, Object> map = new HashMap<String, Object>(); map.put("hello", "world"); map.put("hello1", "world1"); map.put("hello2", "world2"); JSONValue.writeJSONString(map, strBuffer, JSONStyle.NO_COMPRESS); // JSONValue.writeJSONString(map, strBuffer, JSONStyle.MAX_COMPRESS); // 如果设置JSONStyle.MAX_COMPRESS，那么strBuffer输出： zhangsan{hello:world,hello2:world2,hello1:world1} System.out.println(strBuffer); } }

输出：

true {\"balance\":1000.21,\"num\":100,\"nickname\":null,\"is_vip\":true,\"name\":\"foo\",\"is_special_fuhao\":\"'\"} {"balance":1000.21,"num":100,"nickname":null,"is_vip":true,"name":"foo","is_special_fuhao":"'"} {"balance":1000.21,"num":100,"nickname":null,"is_vip":true,"name":"foo","is_special_fuhao":"'"} {"balance":1000.21,"num":100,"nickname":null,"is_vip":true,"name":"foo","is_special_fuhao":"'"} {balance:1000.21,num:100,is_vip:true,name:foo,is_special_fuhao:"'"} {balance:1000.21,num:100,is_vip:true,name:foo,is_special_fuhao:"'"} {balance:1000.21,num:100,nickname:null,is_vip:true,name:foo,is_special_fuhao:"'"} {"balance":1000.21,"num":100,"nickname":null,"is_vip":true,"name":"foo","is_special_fuhao":"'"} {"balance":1000.21,"num":100,"is_vip":true,"name":"foo","is_special_fuhao":"'"} {balance=1000.21, num=100, nickname=null, is_vip=true, name=foo, is_special_fuhao='} {"balance":1000.21,"num":100,"is_vip":true,"nickname":null,"name":"foo","is_special_fuhao":"'"} ********************************** {"key":"Value"} {"key":"Value"} Value ********************************** zhangsan{"hello":"world","hello2":"world2","hello1":"world1"}

JSONValue中所有的parse方法内部都是调用JSONParser实现的parse的方法。

JSONValue.parse() 和 JSONValue.parseStrict() 功能是一致的。区别是JSONValue.parse()不会抛出异常，而JSONValue.parseStrict()会抛出ParseException异常。