Java Jackson - prevent float to int conversion when deserializing

Question

I have a JSON payload with the following structure ...

{
\"age\": 12
}

... which is mapped to the following class:

public c         


        

Answer 1

A floating-point value will be truncated to an integer value by default from Jackson 2.6. As indicated in a previous answer, setting ACCEPT_FLOAT_AS_INT to false should fix your problem.

@Test(expected = JsonMappingException.class)
public void shouldFailMarshalling() throws IOException {
    final String student = "{\"age\": 12.5}";
    final ObjectMapper mapper = new ObjectMapper();

    // don't accept float as integer
    mapper.configure(ACCEPT_FLOAT_AS_INT, false);
    mapper.readValue(student, Student.class);
}