当成员类型和访问器方法不一致时，通过引用链访问com.fasterxml.jackson.DataBind.JSONMappingException

Question

    public class EventArgs {

        private Long id;
        private String message;


        public String getMessage() {
            return message;
        }

        public void setMessage(String message) {
            this.message = message;
        }

        public long getId() {
            return id;
        }

        public void setId(long id) {
            this.id = id;
        }

}

@Test
    public void shouldSerializeToString() {

        ObjectMapper mapper = new ObjectMapper();
        String value = null;
        try {
            value = mapper.writeValueAsString(new EventArgs());
        } catch (JsonProcessingException e) {
            e.printStackTrace();
        }

        Assert.assertNotNull(value);
    }

Answer 1

您可以告诉Jackson不要使用getters和setters，只使用字段：

ObjectMapper mapper = new ObjectMapper();
mapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.NONE); //turn off everything
mapper.setVisibility(PropertyAccessor.FIELD, JsonAutoDetect.Visibility.ANY); // only use fields

或者，如果您希望仅禁用getter和setter并使用字段（并允许其他字段，如JsonCreator）：

mapper.setVisibility(PropertyAccessor.SETTER, JsonAutoDetect.Visibility.NONE);
mapper.setVisibility(PropertyAccessor.GETTER, JsonAutoDetect.Visibility.NONE);
mapper.setVisibility(PropertyAccessor.FIELD, JsonAutoDetect.Visibility.ANY);

输出JSON是：

{"id":null,"message":null}