SpringBootTest中的HttpMessageNotWritableException

Question

我已经创建了一个控制器，它实际上在我的TestCase中以错误告终。有很少其他控制器，我做了相同的方式，那里的测试工作。目前我正在寻找一个解决方案，但我被困了几个小时。

以下testcase失败，因为它导致http错误500而不是200

@ActiveProfiles("Test")
@AutoConfigureMockMvc
@AutoConfigureTestDatabase(replace = AutoConfigureTestDatabase.Replace.NONE)
@Transactional
@SpringBootTest


. . .
@Test
public void whenCreateCustomer_ThenReturnIt() throws Exception {
    String customerName = "foobar2";
    MvcResult result = mvc.perform(post(REST_CUSTOMERS)
            .header(HEADER_AUTH_KEY, authTokenAdminUser.getToken())
            .contentType(MediaType.APPLICATION_JSON)
            .content("{\n" +
                    "  \"name\": \""+ customerName + "\"" +
                    "}")
    )
            .andExpect(status().isOk())
            .andReturn();

    String responseString = result.getResponse().getContentAsString();
    CustomerEntity customer = objectMapper.readValue(responseString, CustomerEntity.class);
    assertThat(customer).isNotNull();

    assertThat(customer.getName()).isEqualTo(customerName);
    assertThat(customer.getCreated()).isNotNull();
}

下面是正在测试的方法。我已经调试过了，看起来不错。实体已经被创建，而且到了ResponseEntity应该返回ok的时候，实体就在它的主体中。我还计算了这个返回responseentity.ok（）.body（createdcustomer.get（））；在调试器中，它工作了。

@Override
@PostMapping
public ResponseEntity<CustomerDTO> create(@RequestBody CustomerDTO dto) {
    dto.setId(uidService.getNextUidScServer());
    if (dto.getCreated() == null){
        dto.setCreated(LocalDateTime.now());
    }
    Optional<CustomerDTO> createdCustomer = customerService.create(dto);
    if (createdCustomer.isPresent()){
        return ResponseEntity.ok().body(createdCustomer.get());
    }
    else{
        return ResponseEntity.badRequest().build();
    }
}

Async:
  Async started = false
   Async result = null

  Resolved Exception:
          Type = org.springframework.http.converter.HttpMessageNotWritableException

    @NoArgsConstructor
    @AllArgsConstructor
    @Data
    @Entity
    @Builder
    @Table(name = "Customer")
    public class CustomerEntity {


        @Id
        @Column(name = "uid")
        private Long id;

        @Column(name = "name")
        private String name;

        @Column(name = "created")
        private LocalDateTime created;

        @OneToMany(
                mappedBy = "customer",
                cascade = CascadeType.ALL,
                orphanRemoval = true)
        List<PenEntity> pen;

    @Data
    @AllArgsConstructor
    @NoArgsConstructor
    public class CustomerDTO {

        private Long id;
        private String name;

        @JsonDeserialize(using = LocalDateDeserializer.class)
        @JsonSerialize(using = LocalDateSerializer.class)
        private LocalDateTime created;

        @JsonIgnore
        private List<PenEntity> pen;
    }

Answer 1

您没有使用正确的序列化程序。必须使用LocalDateTimeSerializer，而不是LocalDateSerializer。

@Data
    @AllArgsConstructor
    @NoArgsConstructor
    public class CustomerDTO {

        private Long id;
        private String name;

        @JsonDeserialize(using = LocalDateTimeDeserializer.class)
        @JsonSerialize(using = LocalDateTimeSerializer.class)
        private LocalDateTime created;

        @JsonIgnore
        private List<PenEntity> pen;
    }

你说你用了断点。以后，如果您有一个不理解的异常，请在该异常的构造函数中使用断点。然后，使用堆栈跟踪来确定哪个类引发了异常，以及如何修复它。
在我的调试器中，我看到了以下内容：

“无法写入JSON：无法将类java.time.LocalDateTime转换为类java.time.LocalDate（java.time.LocalDateTime和java.time.LocalDate位于加载程序”bootstrap“的模块java.base中）”