Java Android REST POST丢失日期值

我有一个Android应用程序（Spring Android+Android Annotations+Gson），它使用Web应用程序（Jersey+Spring+Hibernate/JPA）提供的REST服务。问题是我的java.util.Date属性没有序列化：

活动（Android应用程序）：

...
@Click(R.id.buttonLogin)
void onLoginClick() {
    Student student = new Student();
    student.setDateRegistration(new Date()); //Property where the problem occurs
    student.setFirstName("Venilton");
    student.setGender(Gender.M);

    doSomethingInBackground(student);
}

@Background
void doSomethingInBackground(Student student) {
    this.restClient.insert(student);
}
...

@Rest(rootUrl = "http://MY_IP:8080/restful-app", 
    converters = { GsonHttpMessageConverter.class })
public interface StudentRESTfulClient {

    @Post("/student/insert")
    Student insert(Student student);
}

@Component
@Path("/student")
public class StudentRESTfulServer {

    @Autowired
    private StudentService studentServiceJpa;

    @POST 
    @Path("/insert")
    public Student insert(Student student) {
        //student.getDateRegistration() is null! It's a problem!

        Student studentResponse = null;
        try {
                this.studentServiceJpa.insert(student);
                studentResponse = student;
        } catch (Exception exception) { }

        return studentResponse;
    }
}

Rest客户端（Android应用程序）：

...
@Click(R.id.buttonLogin)
void onLoginClick() {
    Student student = new Student();
    student.setDateRegistration(new Date()); //Property where the problem occurs
    student.setFirstName("Venilton");
    student.setGender(Gender.M);

    doSomethingInBackground(student);
}

@Background
void doSomethingInBackground(Student student) {
    this.restClient.insert(student);
}
...

@Rest(rootUrl = "http://MY_IP:8080/restful-app", 
    converters = { GsonHttpMessageConverter.class })
public interface StudentRESTfulClient {

    @Post("/student/insert")
    Student insert(Student student);
}

@Component
@Path("/student")
public class StudentRESTfulServer {

    @Autowired
    private StudentService studentServiceJpa;

    @POST 
    @Path("/insert")
    public Student insert(Student student) {
        //student.getDateRegistration() is null! It's a problem!

        Student studentResponse = null;
        try {
                this.studentServiceJpa.insert(student);
                studentResponse = student;
        } catch (Exception exception) { }

        return studentResponse;
    }
}

Rest服务器（Web应用）：

...
@Click(R.id.buttonLogin)
void onLoginClick() {
    Student student = new Student();
    student.setDateRegistration(new Date()); //Property where the problem occurs
    student.setFirstName("Venilton");
    student.setGender(Gender.M);

    doSomethingInBackground(student);
}

@Background
void doSomethingInBackground(Student student) {
    this.restClient.insert(student);
}
...

@Rest(rootUrl = "http://MY_IP:8080/restful-app", 
    converters = { GsonHttpMessageConverter.class })
public interface StudentRESTfulClient {

    @Post("/student/insert")
    Student insert(Student student);
}

@Component
@Path("/student")
public class StudentRESTfulServer {

    @Autowired
    private StudentService studentServiceJpa;

    @POST 
    @Path("/insert")
    public Student insert(Student student) {
        //student.getDateRegistration() is null! It's a problem!

        Student studentResponse = null;
        try {
                this.studentServiceJpa.insert(student);
                studentResponse = student;
        } catch (Exception exception) { }

        return studentResponse;
    }
}

Android应用程序执行REST服务的学生对象发布，但当学生对象到达StudentRESTfulServer时，DateRegistration属性将失去其值。

---

你能帮我吗？

显然，Gson不知道如何正确地序列化你的日期（有点奇怪，它没有向日志中添加任何内容，是吗？）

简单的解决方案是设置您将要使用的Gson日期格式。 为此，您需要创建自定义转换器并使用它，而不是

GsonHttpMessageConverter

CustomHttpMessageConverter.java

CustomHttpMessageConverter extends GsonHttpMessageConverter {
    protected static final String DATE_FORMAT = "yyyy-MM-dd";

    protected static Gson buildGson() {
        GsonBuilder gsonBuilder = new GsonBuilder();

        gsonBuilder.setDateFormat(DATE_FORMAT);

        return gsonBuilder.create();
    }

    public CustomHttpMessageConverter()  {
        super(buildGson());
    }
}

然后在您的REST客户端（Android应用程序）

这应该很管用

如果仍然不工作

然后，您可以在

buildGson

方法中添加Gson所需的任何设置，例如，如果需要，您可以注册自定义序列化程序：

    gsonBuilder.registerTypeAdapter(Date.class, new GsonDateDeSerializer());

但是，您需要在

GsonDateDeSerializer

类中实现

JsonDeserializer

和

JsonSerializer

接口

---

对于自定义序列化/反序列化，您可以查看我的另一个答案：

请从客户端和服务器发布您的学生模型。我强烈感觉Date（）不能在json上序列化，所以您应该使用字符串或长值。您好@MemLeak，我的学生实体很好：

@XmlRootElement

公共类学生实现可序列化{

@Column（name=“Date\u last\u login”，nullable=false）

私人日期dateLastLogin；
尽量将时间戳存储为Date:student.setDateRegistration（System.currentTimeMillis（））Damian Walczak感谢您的回答！对我来说非常有意义，我们将尽快进行测试。