java如何利用FastJSON、Gson、Jackson三种Json格式工具自定义时间序列化

\/Date(1296576000000+0800)\/

Date now = new Date();
String nowStr = String.format("\\/Date(%s+0800)\\/", now.getTime());

compile group: 'com.google.code.gson', name: 'gson', version: '2.8.1'
compile group: 'com.alibaba', name: 'fastjson', version: '1.2.36'
compile group: 'com.fasterxml.jackson.core', name: 'jackson-databind', version: '2.9.0'

public class StringSmallUtils {

  /**
   * 时间类型格式转换为指定的String类型
   *
   * @param date
   * @return
   */
  protected static String DateToSpecialString(Date date) {
    if (date == null)
      return null;
    return String.format("\\/Date(%s+0800)\\/", date.getTime());
  }

  /**
   * 指定的String类型转换为时间类型格式
   *
   * @param str
   * @return
   */
  protected static Date SpecialStringToDate(String str) {
    if (isEmpty(str))
      return null;
    if (!contains(str,"Date"))
      return null;
    str = str.replace("\\/Date(", "").replace("+0800)\\/", "").trim();
    return new Date(Long.parseLong(str));
  }


  /**
   * 判断字符串是否包含输入的字符串
   *
   * @param str
   * @param searchStr
   * @return
   */
  public static boolean contains(String str, String searchStr) {
    if (str == null || searchStr == null) {
      return false;
    }
    return str.contains(searchStr);
  }

  /**
   * 判断字符串是否为空
   *
   * @param str
   * @return
   */
  public static boolean isEmpty(String str) {
    return ((str == null) || (str.trim().isEmpty()));
  }
}

public class GsonCustomerDateJsonSerializer implements JsonSerializer<Date>, JsonDeserializer<Date> {
  @Override
  public JsonElement serialize(Date src, Type typeOfSrc, JsonSerializationContext context) {
    return new JsonPrimitive(StringSmallUtils.DateToSpecialString(src));
  }

  @Override
  public Date deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
    return StringSmallUtils.SpecialStringToDate(json.getAsString());
  }
}

public class Program {
  public static void main(String[] args) throws JsonProcessingException {
    Date start = new Date();
    Gson gson = new GsonBuilder().registerTypeAdapter(Date.class, new GsonCustomerDateJsonSerializer()).create();
    String gsonStr = gson.toJson(createUser());
    Date end = new Date();
    long interval = (end.getTime() - start.getTime());
    System.out.println(String.format("Gson序列化之后的字符串:%s，花费时间%d毫秒", gsonStr, interval));
  }

  private static User createUser() {
    User user = new User();
    user.setName("张三");
    user.setAge(21);
    user.setLastlogintime(new Date());
    return user;
  }
}

public class FastJsonCustomerDateJsonSerializer implements ObjectSerializer, ObjectDeserializer {
  @Override
  public void write(JSONSerializer serializer, Object object, Object fieldName, Type fieldType, int features) throws IOException {
    SerializeWriter out = serializer.getWriter();
    out.write(StringSmallUtils.DateToSpecialString((Date) object));
  }

  @Override
  public <T> T deserialze(DefaultJSONParser parser, Type type, Object fieldName) {
    return (T) StringSmallUtils.SpecialStringToDate(parser.getInput());
  }

  @Override
  public int getFastMatchToken() {
    return 0;
  }
}

public class Program {
  public static void main(String[] args) throws JsonProcessingException {
    Date start1 = new Date();
    SerializeConfig mapping = new SerializeConfig();
    mapping.put(Date.class, new FastJsonCustomerDateJsonSerializer());
    String fastjsonStr = JSON.toJSONString(createUser(), mapping);
    Date end1 = new Date();
    long interval1 = (end1.getTime() - start1.getTime());
    System.out.println(String.format("FastJSON序列化之后的字符串:%s，花费时间%d毫秒", fastjsonStr, interval1));
  }

  private static User createUser() {
    User user = new User();
    user.setName("张三");
    user.setAge(21);
    user.setLastlogintime(new Date());
    return user;
  }
}

public class JacksonCustomerDateJsonSerializer extends JsonSerializer<Date> {
  @Override
  public void serialize(Date value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
    gen.writeString(StringSmallUtils.DateToSpecialString(value));
  }
}

public class JacksonCustomerDateJsonDeserializer extends JsonDeserializer<Date> {
  @Override
  public Date deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {
    return StringSmallUtils.SpecialStringToDate(p.getText());
  }
}

public class Program {
  public static void main(String[] args) throws JsonProcessingException {
    Date start2 = new Date();
    ObjectMapper mapper = new ObjectMapper();
    SimpleModule module = new SimpleModule();
    module.addSerializer(Date.class, new JacksonCustomerDateJsonSerializer());
    module.addDeserializer(Date.class, new JacksonCustomerDateJsonDeserializer());
    mapper.registerModule(module);
    String jacksonStr = mapper.writeValueAsString(createUser());
    Date end2 = new Date();
    long interval2 = (end2.getTime() - start2.getTime());
    System.out.println(String.format("Jackson序列化之后的字符串:%s，花费时间%d毫秒", jacksonStr, interval2));
  }

  private static User createUser() {
    User user = new User();
    user.setName("张三");
    user.setAge(21);
    user.setLastlogintime(new Date());
    return user;
  }
}