无法构造 `java.time.ZonedDateTime` 的实例（不存在创建者，如默认构造）

Posted 2023-02-26

【中文标题】无法构造 `java.time.ZonedDateTime` 的实例（不存在创建者，如默认构造）

【英文标题】：Cannot construct instance of `java.time.ZonedDateTime` (no Creators, like default construct, exist)

【发布时间】：2018-11-05 12:21:03

【问题描述】：

我在 JAX-RS 1.0 下学习 Jackson。服务器返回 HTTP 响应如下：

  "url": "http://localhost:8080/api/123",
  "created": "2018-05-26T09:21:26.301+02:00"

我需要将 JSON 响应反序列化为一个名为 ProductCreated 的 Java 对象：

public class ProductCreated 

  @JsonProperty("created")
  private final ZonedDateTime created;

  @JsonProperty("url")
  private final String url;

  public ProductCreated(String url) 
    this.url = url;
    this.created = ZonedDateTime.now();
  

  @JsonCreator
  public ProductCreated(
      @JsonProperty("url") String url,
      @JsonProperty("created") ZonedDateTime created) 
    this.url = url;
    this.created = created;
  

  public String getUrl() 
    return url;
  

  public ZonedDateTime getCreated() 
    return created;
  

在我的测试中，构造ProductCreated对象失败：

Product p = new Product("123", "foo");
ProductCreated c = wr.type(MediaType.APPLICATION_JSON)
                     .accept(MediaType.APPLICATION_JSON)
                     .post(ProductCreated.class, p);

而客户端错误是：

无法构造java.time.ZonedDateTime 的实例（没有创建者，如默认构造，存在）：没有字符串参数构造函数/工厂方法从字符串值反序列化（'2018-05-26T09:21:26.301+02:00' )

在服务器端，我配置了 JSON 映射器（但对我的测试没有影响，因为测试是客户端？）：

private static JacksonJsonProvider newJacksonJsonProvider() 
  ObjectMapper mapper =
      new ObjectMapper()
          .registerModule(new ParameterNamesModule())
          .registerModule(new Jdk8Module())
          .registerModule(new JavaTimeModule()); // new module, NOT JSR310Module
  mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
  mapper.setDateFormat(new StdDateFormat());
  return new JacksonJsonProvider(mapper);

我在这里错过了什么？

---

完整的堆栈跟踪：

objc[91369]: Class JavaLaunchHelper is implemented in both /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/bin/java (0x10fe224c0) and /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/libinstrument.dylib (0x11164e4e0). One of the two will be used. Which one is undefined.
May 26, 2018 9:48:29 AM com.sun.jersey.server.impl.application.WebApplicationImpl _initiate
INFO: Initiating Jersey application, version 'Jersey: 1.19.4 05/24/2017 03:46 PM'
May 26, 2018 9:48:31 AM org.glassfish.grizzly.http.server.NetworkListener start
INFO: Started listener bound to [localhost:8080]
May 26, 2018 9:48:31 AM org.glassfish.grizzly.http.server.HttpServer start
INFO: [HttpServer] Started.
May 26, 2018 9:48:31 AM io.mincong.shop.rest.MyRequestFilter filter
INFO: filter
May 26, 2018 9:48:31 AM org.glassfish.grizzly.http.server.NetworkListener stop
INFO: Stopped listener bound to [localhost:8080]

com.sun.jersey.api.client.ClientHandlerException: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `java.time.ZonedDateTime` (no Creators, like default construct, exist): no String-argument constructor/factory method to deserialize from String value ('2018-05-26T09:48:31.622+02:00')
 at [Source: (sun.net.www.protocol.http.HttpURLConnection$HttpInputStream); line: 1, column: 50] (through reference chain: io.mincong.shop.rest.dto.ProductCreated["created"])

    at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:644)
    at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:586)
    at com.sun.jersey.api.client.WebResource.handle(WebResource.java:686)
    at com.sun.jersey.api.client.WebResource.access$200(WebResource.java:74)
    at com.sun.jersey.api.client.WebResource$Builder.post(WebResource.java:570)
    at io.mincong.shop.rest.ProductResourceIT.createProduct(ProductResourceIT.java:53)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `java.time.ZonedDateTime` (no Creators, like default construct, exist): no String-argument constructor/factory method to deserialize from String value ('2018-05-26T09:48:31.622+02:00')
 at [Source: (sun.net.www.protocol.http.HttpURLConnection$HttpInputStream); line: 1, column: 50] (through reference chain: io.mincong.shop.rest.dto.ProductCreated["created"])
    at com.fasterxml.jackson.databind.exc.InvalidDefinitionException.from(InvalidDefinitionException.java:67)
    at com.fasterxml.jackson.databind.DeserializationContext.reportBadDefinition(DeserializationContext.java:1451)
    at com.fasterxml.jackson.databind.DeserializationContext.handleMissingInstantiator(DeserializationContext.java:1027)
    at com.fasterxml.jackson.databind.deser.ValueInstantiator._createFromStringFallbacks(ValueInstantiator.java:371)
    at com.fasterxml.jackson.databind.deser.std.StdValueInstantiator.createFromString(StdValueInstantiator.java:323)
    at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromString(BeanDeserializerBase.java:1366)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeOther(BeanDeserializer.java:171)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:161)
    at com.fasterxml.jackson.databind.deser.SettableBeanProperty.deserialize(SettableBeanProperty.java:529)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeWithErrorWrapping(BeanDeserializer.java:528)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeUsingPropertyBased(BeanDeserializer.java:417)
    at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromObjectUsingNonDefault(BeanDeserializerBase.java:1280)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:326)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:159)
    at com.fasterxml.jackson.databind.ObjectReader._bind(ObjectReader.java:1574)
    at com.fasterxml.jackson.databind.ObjectReader.readValue(ObjectReader.java:965)
    at com.fasterxml.jackson.jaxrs.base.ProviderBase.readFrom(ProviderBase.java:815)
    at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:634)
    ... 29 more

【问题讨论】：

你看过github.com/FasterXML/jackson-modules-java8吗？我没有使用它的经验，但它说它“支持 Java 8 日期/时间类型（在 JSR-310 规范中指定）”，其中包括 ZonedDateTime。

请发布整个堆栈跟踪？这是客户端还是服务器端错误？在哪里注册JacksonJsonProvider？服务端和客户端都需要注册。

@OleV.V.是的，我阅读了您指出的回购协议。我认为由于jackson-modules-java8，服务器端可以正常运行，但是客户端无法反序列化数据，因为缺少一些注释。

@PaulSamsotha 我提供了整个堆栈跟踪。确实，我没有在客户端注册JacksonJsonProvider，这可能是问题所在……

是的，您可以在堆栈跟踪中看到这是客户端错误

【参考方案1】：

正如@PaulSamsotha 所指出的，我也需要在客户端注册 JacksonJsonProvider：

ClientConfig cc = new DefaultClientConfig();
cc.getSingletons().add(ShopApplication.newJacksonJsonProvider());
wr = Client.create(cc).resource(Main.BASE_URI.resolve("products"));

其中包含定制的解决方案：

private static JacksonJsonProvider newJacksonJsonProvider() 
  ObjectMapper mapper =
      new ObjectMapper()
          .registerModule(new ParameterNamesModule())
          .registerModule(new Jdk8Module())
          .registerModule(new JavaTimeModule()); // new module, NOT JSR310Module
  mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
  mapper.setDateFormat(new StdDateFormat());
  return new JacksonJsonProvider(mapper);

【参考方案2】：

我能够使用此代码反序列化带有 ZonedDateTime 的 JSON 文件。

ObjectMapper objectMapper = new ObjectMapper()
objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
objectMapper.registerModule(new JavaTimeModule())
MyObject myObject = objectMapper.readValue(new File("src/test/resources/data/my_object.json"), MyObject.class)

【讨论】：

这也适用于 Kotlin，但有一个补充：objectMapper.registerModule(KotlinModule())。