JsonFormat does not affect serialisation of Date

i use spring boot 1.3.0 (tried to 1.3.0.M5), spring-data-jpa, spring rest and mysql. i use java 8.

In my dto i have

@JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "dd/MM/yyyy", timezone="EST")
private Date birthdate;

client still continue to receive yyyy-mm-dd

[marccollin]

if i use @Temporal(javax.persistence.TemporalType.TIMESTAMP)

that work.

[wilkinsona]

This doesn’t have anything to do with Spring Boot. You’re returning a java.sql.Date and Jackson doesn’t appear to apply the specified formatting to it. You can see the problem with the following code that doesn’t involve Boot at all:

    public static void main(String[] args) throws JsonProcessingException {
        ObjectMapper objectMapper = new ObjectMapper();
        System.out.println(objectMapper.writeValueAsString(new Foo(new java.util.Date())));
        System.out.println(objectMapper.writeValueAsString(new Foo(new java.sql.Date(System.currentTimeMillis()))));
    }

    static class Foo {

        @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "dd/MM/yyyy", timezone="EST")
        private Date birthdate;

        public Foo() {

        }

        public Foo(Date birthdate) {
            this.birthdate = birthdate;
        }

        public Date getBirthdate() {
            return birthdate;
        }

    }

It produces the following output:

{"birthdate":"01/10/2015"}
{"birthdate":"2015-10-01"}

Note that the Jackson documentation has this to say about java.sql.Date:

Notes on java.sql.Date

(aka “Please do NOT use java.sql.Date, ever!”)

Although Jackson supports java.sql.Date, there are known issues with respect to timezone handling, partly due to design of this class. It is recommended that this type is avoided, if possible, and regular java.util.Date (or java.util.Calendar) used instead. If this is not possible, it may be necessary for applications to convert these dates using java.util.Calendar and explicit timezone definition.