Gson 与 fastJson 在使用上的差别（fastJson的优势）

1、android 经常使用的json解析方式

Android 开发上经常使用的json解析方式有：Gson， fastJson，jackson。 
由于jackjson jar包会比较大点（700+k），Gson和fastjson的功能又基本够用，因此一直没正式用过jackjson。本身有用的就是Gson和fastjson

2、基本使用方式

Gson

//解成对象
    Fromat mFromat = new Gson().fromJson(jsonStringObject, Fromat.class); //解成对象组 LinkedList<Fromat> list = new LinkedList<MainActivity.Fromat>(); Type type = new TypeToken<LinkedList<Fromat>>(){}.getType(); list = new Gson().fromJson(jsonStringArray, type); //泛型统一封装时 须要传个 type 进来 new TypeToken<LinkedList<Fromat>>(){}.getType(); fromJson(String json, Type typeOfT) public <T> T fromJson(String json, Type typeOfT)

fastJson

//解析成对象
    Fromat fastjsonObject = JSON.parseObject(jsonObjectString, Fromat.class); //解析成对象组 List<Fromat> fastjsonArray = JSON.parseArray(jsonArrayString, Fromat.class); //泛型统一封装时 须要传个 type 进来 或者TypeReference 也能够也是调用的type new TypeReference<Fromat>() {} new TypeReference<Fromat>() {}.getType() public static <T> T parseObject(String input, Type clazz, Feature... features) public static <T> T parseObject(String text, TypeReference<T> type, Feature... features)

3、fastjson 的优势

可维护性 > 正确性 > 性能 
说点实在的，Gson在遇到 {} [] 这种json关键字的时候直接解析为string 报错。fastjson是能够解析 
demo代码：

String jsonObjectString = "{\"status\": 0}"; String jsonArrayString = "[{\"status\": 0}]"; //fastJson String fastjsonObject = JSON.parseObject(jsonObjectString, String.class); Log.d("test", "fastJson string {} = " + fastjsonObject); String fastjsonArray = JSON.parseObject(jsonArrayString, String.class); Log.d("test", "fastJson string [] = " + fastjsonArray); //Gson try { String gsonObject = new Gson().fromJson(jsonObjectString, String.class); Log.d("test", "gson string {} = " + gsonObject); }catch (Exception e){ Log.d("test", "gson string {} = " + e); } try { String gsonArray = new Gson().fromJson(jsonArrayString, String.class); Log.d("test", "gson string {} = " + gsonArray); }catch (Exception e){ Log.d("test", "gson string [] = " + e); }

结果： D/test: fastJson string {} = {“status”:0} D/test: fastJson string [] = [{“status”:0}] D/test: gson string {} = com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: D/test: gson string [] = com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected a string but was BEGIN_ARRAY at line 1 column 2 path $

 

from: http://www.voidcn.com/blog/lckj686/article/p-6000736.html