gson高级使用

> 类型格式TypeTokenType listType = new TypeToken<ArrayList<Person>>(){}.getType();> 时间输出格式GsonBuilder builder = new GsonBuilder();builder.setDateFormat("yyyy年MM月dd HH:mm:ss"); Gson gson = builder.create();> 别名String JSON_DATA_STRING = {    nick_name: "sagomilk"}public class Person {       @SerializedName("nick_name")    public String name;}gson.fromJson(JSON_DATA_STRING, Person.class);> 支持null输出Gson includeNullsGson = gsonBuilder.serializeNulls().create();> 禁用html转义Gson unescapingGson = new GsonBuilder().disableHtmlEscaping().create();> 通过访问修饰符控制序列化和反序列化访问修饰符包括：public、private、protected、static 、final等，注意：static 会自动被排除。   public class User {          private String name;          public boolean sex;          static int age;      final String homeAddress;      }      Gson gson = new GsonBuilder().excludeFieldsWithModifiers(    Modifier.FINAL,Modifier.PRIVATE).create();      System.out.println(gson.toJson(user));      // 结果：{"sex":true}  > 多版本支持class VersionClass{    @Since(1.0)     String versionOneField = "1.0";    @Since(2.0)     String versionTwoField = "2.0";}Gson gson = new GsonBuilder().setVersion(1.0).create();> Serializerprivate class DateTimeSerializer implements JsonSerializer<DateTime> {  public JsonElement serialize(DateTime src, Type typeOfSrc, JsonSerializationContext context) {    return new JsonPrimitive(src.toString());  }}> Deserializerprivate class DateTimeDeserializer implements JsonDeserializer<DateTime> {  public DateTime deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context)      throws JsonParseException {    return new DateTime(json.getAsJsonPrimitive().getAsString());  }}> Serialization 和 DeserializationGsonBuilder gson = new GsonBuilder();gson.registerTypeAdapter(MyType2.class, new MyTypeAdapter());gson.registerTypeAdapter(MyType.class, new MySerializer());gson.registerTypeAdapter(MyType.class, new MyDeserializer());gson.registerTypeAdapter(MyType.class, new MyInstanceCreator());> Array - 直接解析成数组    Person[] foos = gson.fromJson(JSON_DATA_STRING, Person[].class);    List<Person> fooList = Arrays.asList(foos); - 解析成为List    Type listType = new TypeToken<ArrayList<Person>>(){}.getType();    ArrayList<Person> foos = gson.fromJson(JSON_DATA_STRING, listType);> Map如果没有对应的Object class，可以直接使用Map.class,但是使用的时候需要执行转换Map m = gson.fromJson(JSON_DATA_STRING, Map.class);> 命名风格setFieldNamingPolicy new GsonBuilder().setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_DASHES).create();> 美化GsonBuilder gsonBuilder = new GsonBuilder();Gson prettyGson = gsonBuilder.setPrettyPrinting().create();