Question

我有这个方法：

/**
 * POST
 */
public static void create(String body) {
    Logger.info("APPOINTMENT create - json string: %s", body);

    Appointment appointment = null;
    try {
        appointment = new Gson().fromJson(body, Appointment.class);

        //services are detached, re-take them from db
        List<Service> refreshedServices = new ArrayList<Service>();
        for (final Service ser : appointment.services) {
            Service service = Service.findById(ser.id);
            refreshedServices.add(service);
        }
        appointment.services = refreshedServices;
        appointment.save();
        appointment.refresh();
        Logger.info("services refreshed");
    } catch (Exception ex) {
        Logger
                .info(
                        "An error has occured when trying to create an APPOINTMENT %s",
                        ex);
        response.status = Http.StatusCode.INTERNAL_ERROR;
        renderJSON(new StatusMessage(
                "An internal error has occured. Please try again later."));
    }

    renderJSON(appointment);
}

我正在测试它：

public void createAppointment(final Contact contact, final List<Service> services) throws Exception {
        Appointment app = new Appointment();
        app.userUid = "cristi-uid";
        app.name = "app1";
        app.contact = contact;

        String serviceAsJson = "{\"userUid\":\"cristi-uid\",\"name\":\"app1\",\"allDay\":false,\"contact\":{\"id\":"+contact.id+"},\"services\":[{\"id\":\""+services.get(0).getId()+"\"},{\"id\":\""+services.get(1).getId()+"\"}]}";
        Response response = POST("/appointment/create", "application/json", serviceAsJson);

        Logger.info("POST was done");
        Appointment appReturned = new Gson().fromJson(response.out.toString(), Appointment.class);

        Logger.info("appointment create response: %s", response.out.toString());

        assertIsOk(response);
        assertEquals(appReturned.name, app.name);
    }

嗯，问题在于它抛出了这个异常：

java.lang.RuntimeException: java.util.concurrent.ExecutionException: play.exceptions.JavaExecutionException
at play.test.FunctionalTest.makeRequest(FunctionalTest.java:304)
at play.test.FunctionalTest.makeRequest(FunctionalTest.java:310)
at play.test.FunctionalTest.POST(FunctionalTest.java:152)
at play.test.FunctionalTest.POST(FunctionalTest.java:120)
at play.test.FunctionalTest.POST(FunctionalTest.java:116)
at AppointmentsTest.createAppointment(AppointmentsTest.java:61)

我无法找出原因。

在它抛出异常后打印出Logger.info("services refreshed"); ......

你们看到这个测试POST有什么问题吗？

更新：似乎问题来自于尝试将appointment呈现为JSON：

Caused by: java.lang.StackOverflowError
at java.util.LinkedHashMap$LinkedHashIterator.(LinkedHashMap.java:345)
at java.util.LinkedHashMap$LinkedHashIterator.(LinkedHashMap.java:345)
at java.util.LinkedHashMap$ValueIterator.(LinkedHashMap.java:387)
at java.util.LinkedHashMap$ValueIterator.(LinkedHashMap.java:387)
at java.util.LinkedHashMap.newValueIterator(LinkedHashMap.java:397)
at java.util.HashMap$Values.iterator(HashMap.java:910)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.write(ReflectiveTypeAdapterFactory.java:192)
at com.google.gson.Gson$FutureTypeAdapter.write(Gson.java:879)
at com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.write(TypeAdapterRuntimeTypeWrapper.java:68)
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.write(CollectionTypeAdapterFactory.java:96)

Answer 1

这是因为：

Play框架与Google的JSON库Gson捆绑在一起，但是这个库的开发人员做了一些设计选择它非常适合生成将要发送的JSON HTTP客户端。

Erik Bakker recommended使用FlexSon

Answer 2

我能够通过下载和研究错误跟踪来确定问题。基本上我的Appointment对象有一些ManyToMany关系，似乎renderJSON在尝试渲染这些关系时给出了StackOverFlow。

我创建了另一个Appointment对象，只复制了我需要导出的字段。

    Appointment appointmentOutput = new Appointment();
    appointmentOutput.id = appointment.id;
    appointmentOutput.name = appointment.name;

    renderJSON(appointmentOutput);

使用JSON进行POST时出现奇怪的ExecutionException

2 个答案: