Java8反射不'；行不通

我们在项目中使用hibernate验证器和动态类加载（通过将类加载到单独的类加载程序中）。在我们意识到该类不是必需的之后，我们删除了对该类和类装入器的所有引用，然后GC收集这些引用

我们得到的：在应用程序启动后的一段时间，java反射停止工作

java.lang.reflect.UndeclaredThrowableException: null
    at com.sun.proxy.$Proxy253.equals(Unknown Source)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintValidatorManager$CacheKey.equals(ConstraintValidatorManager.java:287)
    at java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:940)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintValidatorManager.getInitializedValidator(ConstraintValidatorManager.java:104)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.getConstraintValidatorNoUnwrapping(ConstraintTree.java:301)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.getConstraintValidatorInstanceForAutomaticUnwrapping(ConstraintTree.java:242)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.getInitializedConstraintValidator(ConstraintTree.java:163)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.validateConstraints(ConstraintTree.java:116)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.validateComposingConstraints(ConstraintTree.java:396)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.validateConstraints(ConstraintTree.java:98)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.validateConstraints(ConstraintTree.java:87)
    at org.hibernate.validator.internal.metadata.core.MetaConstraint.validateConstraint(MetaConstraint.java:73)
    at org.hibernate.validator.internal.engine.ValidatorImpl.validateMetaConstraint(ValidatorImpl.java:616)
    at org.hibernate.validator.internal.engine.ValidatorImpl.validateConstraint(ValidatorImpl.java:581)
    at org.hibernate.validator.internal.engine.ValidatorImpl.validateConstraintsForSingleDefaultGroupElement(ValidatorImpl.java:527)
    at org.hibernate.validator.internal.engine.ValidatorImpl.validateConstraintsForDefaultGroup(ValidatorImpl.java:495)
    at org.hibernate.validator.internal.engine.ValidatorImpl.validateConstraintsForCurrentGroup(ValidatorImpl.java:460)
    at org.hibernate.validator.internal.engine.ValidatorImpl.validateInContext(ValidatorImpl.java:410)
    at org.hibernate.validator.internal.engine.ValidatorImpl.validate(ValidatorImpl.java:207)
    at org.springframework.validation.beanvalidation.SpringValidatorAdapter.validate(SpringValidatorAdapter.java:281)
    ... Many spring filters calls ...
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.springframework.web.multipart.support.MultipartFilter.doFilterInternal(MultipartFilter.java:122)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at *someAwesomePackage*.microservice.rest.spring.webapp.CabinetRequestFilter.doFilterInternal(CabinetRequestFilter.java:98)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803)
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459)
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.reflect.InvocationTargetException: null
    at sun.reflect.GeneratedMethodAccessor268.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.hibernate.validator.internal.util.annotationfactory.AnnotationProxy.invoke(AnnotationProxy.java:69)
    ... 260 common frames omitted
Caused by: java.lang.NullPointerException: null
    at org.hibernate.validator.internal.util.annotationfactory.AnnotationProxy.getAnnotationMemberValue(AnnotationProxy.java:248)
    at org.hibernate.validator.internal.util.annotationfactory.AnnotationProxy.equals(AnnotationProxy.java:104)
    ... 264 common frames omitted

此处发生错误（来自java.lang.Class.java的方法）：

映射示例：

@XmlRootElement(name = "SELFCARE")
@XmlAccessorType(XmlAccessType.FIELD)
public class Session {

    @XmlElement(name = "SESSION_ID")
    private String sessionId;
}

分析异常：

WARN  2017.12.25 20:00:05.991 +0300 org.apache.cxf.jaxrs.provider.AbstractJAXBProvider             javax.xml.bind.UnmarshalException
- with linked exception:
[com.sun.istack.SAXParseException2; lineNumber: 1; columnNumber: 1; unexpected element (uri:"", local:"SELFCARE"). Expected elements are <{}SELFCARE>]
    at com.sun.xml.bind.v2.runtime.unmarshaller.UnmarshallerImpl.handleStreamException(UnmarshallerImpl.java:483)
    at com.sun.xml.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal0(UnmarshallerImpl.java:417)
    at com.sun.xml.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal(UnmarshallerImpl.java:386)
    at org.apache.cxf.jaxrs.provider.JAXBElementProvider.unmarshalFromInputStream(JAXBElementProvider.java:294)
    at org.apache.cxf.jaxrs.provider.JAXBElementProvider.doUnmarshal(JAXBElementProvider.java:245)

WARN 2017.12.25 20:00:05.991+0300 org.apache.cxf.jaxrs.provider.AbstractJAXBProvider javax.xml.bind.UnmarshalException
-除此之外：
[com.sun.istack.SAXParseException2；行号：1；列号：1；意外元素（uri:，local:“SELFCARE”）。预期元素为]
位于com.sun.xml.bind.v2.runtime.unmarshaller.UnmarshallerImpl.handleStreamException（UnmarshallerImpl.java:483）
位于com.sun.xml.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal0（UnmarshallerImpl.java:417）
位于com.sun.xml.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal（UnmarshallerImpl.java:386）
位于org.apache.cxf.jaxrs.provider.JAXBElementProvider.unmarshalFromInputStream（JAXBElementProvider.java:294）
位于org.apache.cxf.jaxrs.provider.JAXBElementProvider.doUnmarshal（JAXBElementProvider.java:245）

---

但是映射是正确且有效的，如果反射在工作…

从stacktrace，我怀疑您使用的是HV 5.x。我说得对吗

这个问题似乎与您有一个代理有关。我认为这可能与注释是键的一部分有关

你能试试HV 6.0.7.Final吗？我们不再在这里使用缓存键中的注释，因此它可能会解决您的问题

小心，我们更改了groupId：它现在是org.hibernate.validator（而不是org.hibernate）-如果HV依赖项是从另一个工件传递过来的，请小心，如果需要，请添加排除项

您还需要javax.el依赖项：

<dependency>
   <groupId>org.glassfish</groupId>
   <artifactId>javax.el</artifactId>
   <version>3.0.1-b08</version>
</dependency>

玻璃鱼
javax.el
3.0.1-b08

（请小心，您的依赖项中可能有其他javax.el工件，因此请确保只有这一个——Eclipse的依赖层次视图可能会有所帮助）

您还需要验证api 2.0.1.Final（它随HV传递而来，但如果您显式声明它，则可能必须更改版本）

除此之外，您不应该有任何兼容性问题（除非您使用的是诸如值处理之类的实验性功能）：这是一个替代品。HV 6的速度也明显加快，因此应该是一个双赢的局面

---

请随时在此处报告升级过程中出现的任何问题，我会提供帮助。

您是否尝试过m.getName（）.intern（）==internedName？来自文档：当调用intern方法时，如果池中已经包含一个字符串，该字符串等于由equals（object）方法确定的该字符串对象，则返回池中的字符串。否则，此字符串对象将添加到池中，并返回对此字符串对象的引用。因此，对于任意两个字符串s和t，当且仅当s.equals（t）为true时，s.intern（）==t.intern（）为true。您的类加载器是否将加载延迟/委托给父类加载器？为什么不使用equals而不是

=

。你能用NullpointerException标记这行吗？从我的观点来看，字符串插入不会导致this@Kaushal是的，我尝试在调试中调用m.getName（）.intern（）==internedName-它返回true。可能是由于多线程导致的问题？纪尧姆·斯密特，谢谢，它起作用了。但应用程序还是失败了@阿列克西·希皮列夫请帮忙！

WARN  2017.12.25 20:00:05.991 +0300 org.apache.cxf.jaxrs.provider.AbstractJAXBProvider             javax.xml.bind.UnmarshalException
- with linked exception:
[com.sun.istack.SAXParseException2; lineNumber: 1; columnNumber: 1; unexpected element (uri:"", local:"SELFCARE"). Expected elements are <{}SELFCARE>]
    at com.sun.xml.bind.v2.runtime.unmarshaller.UnmarshallerImpl.handleStreamException(UnmarshallerImpl.java:483)
    at com.sun.xml.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal0(UnmarshallerImpl.java:417)
    at com.sun.xml.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal(UnmarshallerImpl.java:386)
    at org.apache.cxf.jaxrs.provider.JAXBElementProvider.unmarshalFromInputStream(JAXBElementProvider.java:294)
    at org.apache.cxf.jaxrs.provider.JAXBElementProvider.doUnmarshal(JAXBElementProvider.java:245)

<dependency>
   <groupId>org.glassfish</groupId>
   <artifactId>javax.el</artifactId>
   <version>3.0.1-b08</version>
</dependency>