Jackson ObjectMapper无法反序列化POJO，引发异常：找不到适合类型[…]的合适构造函数：无法从JSON对象实例化

Question

我尝试测试以下代码没有成功：

class TestClass
{
  private class ND2Customer
  {
    public String name;
    public String description;
    public String email;
    public Boolean multiuser;

    public String dnszone;
    public String uri;
    public String type;

    public ND2Customer()
    {

    }
  }

  @Test
  public void TestJackson() throws JsonParseException, JsonMappingException, IOException
  {
    String json="{\"description\": \"test1u\", \"dnszone\": \"test1.public.sevenltest.example.com.\", \"uri\": \"http://199.127.129.69/customer/test1\", \"multiuser\": true, \"type\": \"2.0.3-3146\", \"email\": \"[e-mail]\", \"name\": \"test1\"}";
    ObjectMapper mapper = new ObjectMapper();

    ND2Customer casted=mapper.readValue(json, ND2Customer.class);

    String castedback=mapper.defaultPrettyPrintingWriter().writeValueAsString(casted);
    System.out.println(castedback);
  } 
}

因为我已经手动覆盖了默认的构造函数，而不是它的子类。

我该如何解决这个问题？

Answer 1

使其静态。杰克逊无法反序列化内部阶级