为什么80%的码农都做不了架构师？>>> 
封装下jackson的序列号操作
public static String ConvertToJson(Object obj) throws Exception {
return mapper.writeValueAsString(obj);
}
public static <T> T ConvertToObject(String json, Class<T> valueType) throws Exception {
return mapper.readValue(json, valueType);
}
public static <T> List<T> ConvertToArray(String json, Class<T> valueType) throws Exception {
JavaType javaType = mapper.getTypeFactory().constructParametricType(ArrayList.class, valueType);
List<T> obj = (List<T>) mapper.readValue(json, javaType);
return obj;
}