为什么jar包冲突会引发 java.lang.ClassNotFoundException错误

今天看了类加载机制,突然有了一个疑惑,根据类加载机制的双亲委派模型,要加载一个类会逐层向上委托加载,直到发起加载请求的类加载器,如果都没加载到就会报 java.lang.ClassNotFoundException错误。但是两个jar包有同名的类为什么会引起 java.lang.ClassNotFoundException这个报错呢

8个回答

两个不同版本的jar包,当ClassLoader要去加载一个类(loadClass)时,要先找到对应的Class的byte数组,Class一般是放在文件中的,当我们有两个jar包里面都包含我们要找的那个相同package的Class时,ClassLoader会找到那个Class呢,这个要看URLClassLoader
中的实现了,因为我们使用到的大部分ClassLoader都是继承URLClassLoader的,URLClassLoader最终将com.lzy.A格式转换成com/lzy/A.class这样的格式delegate给一个URLClassPath类去寻找对应的
文件,是按照字母顺序排序的,也就是a在b前面,1在2前面所以当有两个a-0.1.jar和a-0.2.jar时,首先find到的是a-0.1.jar中class文件,而这个class文件中并没有新版本中定义的方法,这方法解析时就会抛出NoSuchMethodError。

两个jar包有同名的类,虚拟机无法辨别到底是要哪一个

不能有同名的包,!!

同一项目下包名,类名都要唯一啊

逐层向上委托加载是在没有加载到的情况下,你一下加载到两个同名的,这是两回事。

感觉题主很可能是对Java的重载概念有些混淆。
首先重载是一个类与另一个同名类相比有着不同参数与不同返回值,但这两个类本质上是还是一个类,如果这两个类是子类的话必然继承同一个父类。
如果父类不同,且在同一个包内的子类是不可以重名的。
建议题主写jar包的时候最好别把同名类写到一个包里,利用spring的bean工厂标记扫描一下就可以

最好用maven管理jar包版本,这样就很少有这种错误了

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org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872) at javax.servlet.http.HttpServlet.service(HttpServlet.java:661) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.alibaba.druid.support.http.WebStatFilter.doFilter(WebStatFilter.java:123) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at net.sf.ehcache.constructs.web.filter.GzipFilter.doFilter(GzipFilter.java:79) at net.sf.ehcache.constructs.web.filter.Filter.doFilter(Filter.java:93) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.skysz.framework.plugin.dhtmlx.grid.filter.PageHandlerRequestFilter.doFilter(PageHandlerRequestFilter.java:58) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.skysz.framework.filter.csrf.CSRFFilter.doFilter(CSRFFilter.java:92) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.skysz.framework.filter.sql.AntiSqlInjectionfilter.doFilter(AntiSqlInjectionfilter.java:96) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61) at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108) at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66) at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108) at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66) at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449) at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365) at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90) at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83) at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383) at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) 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.springframework.session.web.http.SessionRepositoryFilter.doFilterInternal(SessionRepositoryFilter.java:167) at org.springframework.session.web.http.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:80) 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 com.skysz.framework.filter.encoding.EncodingFilter.doFilter(EncodingFilter.java:36) 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.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:493) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650) 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:800) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:806) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1498) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:745) Caused by: java.lang.ClassNotFoundException: com.ibatis.common.jdbc.exception.NestedSQLException at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1309) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1137) at org.springframework.util.ClassUtils.forName(ClassUtils.java:250) at org.springframework.core.ConfigurableObjectInputStream.resolveClass(ConfigurableObjectInputStream.java:75) at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1612) at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1517) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1771) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1990) at java.io.ObjectInputStream.defaultReadObject(ObjectInputStream.java:500) at java.lang.Throwable.readObject(Throwable.java:914) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1017) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1893) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1990) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1915) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1990) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1915) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:370) at org.springframework.remoting.httpinvoker.AbstractHttpInvokerRequestExecutor.doReadRemoteInvocationResult(AbstractHttpInvokerRequestExecutor.java:292) at org.springframework.remoting.httpinvoker.AbstractHttpInvokerRequestExecutor.readRemoteInvocationResult(AbstractHttpInvokerRequestExecutor.java:243) at org.springframework.remoting.httpinvoker.SimpleHttpInvokerRequestExecutor.doExecuteRequest(SimpleHttpInvokerRequestExecutor.java:96) at org.springframework.remoting.httpinvoker.AbstractHttpInvokerRequestExecutor.executeRequest(AbstractHttpInvokerRequestExecutor.java:138) at org.springframework.remoting.httpinvoker.HttpInvokerClientInterceptor.executeRequest(HttpInvokerClientInterceptor.java:194) at org.springframework.remoting.httpinvoker.HttpInvokerClientInterceptor.executeRequest(HttpInvokerClientInterceptor.java:176) at org.springframework.remoting.httpinvoker.HttpInvokerClientInterceptor.invoke(HttpInvokerClientInterceptor.java:144) ... 89 more ``` ``` ``` 有大神能看出来是什么问题吗 急!!!!感谢
java.lang.UnsupportedClassVersionError: Bad versio
就是在main函数中在引用jxl.jar包 测试读取EXCEL内容时报错(jdk是1.5,jxl.jar版本是_2_6_9),具体错误信息: java.lang.UnsupportedClassVersionError: Bad version number in .class file at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:620) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124) at java.net.URLClassLoader.defineClass(URLClassLoader.java:260) at java.net.URLClassLoader.access$100(URLClassLoader.java:56) at java.net.URLClassLoader$1.run(URLClassLoader.java:195) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:188) at java.lang.ClassLoader.loadClass(ClassLoader.java:306) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268) at java.lang.ClassLoader.loadClass(ClassLoader.java:251) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319) Exception in thread "main" 不知道是什么版本错误,找了半天没找出是哪个地方的错,请各位大侠给看下,谢谢 ! [b]问题补充:[/b] 谢谢您的关注,是在Myeclipse下运行的,可是我的jdk版本是1.5,用的时Myeclipse6.0 这样会有问题吗?
新人求解:JAVA导入外部包后提示java.lang.NoClassDefFoundError
代码如下: ``` package test.copy; import com.jd.open.api.sdk.DefaultJdClient; import com.jd.open.api.sdk.JdClient; import com.jd.open.api.sdk.JdException; import com.jd.open.api.sdk.request.mall.WarePriceGetRequest; import com.jd.open.api.sdk.response.mall.WarePriceGetResponse; public class Tes { public static void main(String[] args) { String SERVER_URL = "https://api.jd.com/routerjson?"; String appKey = "bd……8"; String appSecret = "a7……da"; String accessToken = ""; JdClient client=new DefaultJdClient(SERVER_URL,accessToken,appKey,appSecret); WarePriceGetRequest request=new WarePriceGetRequest(); request.setSkuId("4……2"); try { WarePriceGetResponse response=client.execute(request); System.out.println(response); } catch (JdException e) { e.printStackTrace(); } } } ``` 运行报错如下: Exception in thread "main" java.lang.NoClassDefFoundError: org/codehaus/jackson/map/ObjectMapper at com.jd.open.api.sdk.internal.util.JsonUtil.<clinit>(JsonUtil.java:18) at com.jd.open.api.sdk.request.mall.WarePriceGetRequest.getAppJsonParams(WarePriceGetRequest.java:35) at com.jd.open.api.sdk.DefaultJdClient.buildUrl(DefaultJdClient.java:131) at com.jd.open.api.sdk.DefaultJdClient.execute(DefaultJdClient.java:96) at test.copy.Tes.main(Tes.java:22) Caused by: java.lang.ClassNotFoundException: org.codehaus.jackson.map.ObjectMapper at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) ... 5 more 有小哥哥知道是什么原因吗?233333……
spring cloud zuul 使用注解@EnableZuulProxy项目启动报错,报java.lang.IllegalStateException!
自己搞的一个spring cloud 项目,在网关这里遇到了一个问题,在使用注解@EnableZuulProxy时项目不能启动且报错了,但是使用@EnableZuulServer注解启动一切正常。 报错信息如下: java.lang.IllegalStateException: Error processing condition on org.springframework.cloud.netflix.zuul.ZuulServerAutoConfiguration$ZuulCounterFactoryConfiguration.counterFactory at org.springframework.boot.autoconfigure.condition.SpringBootCondition.matches(SpringBootCondition.java:64) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.context.annotation.ConditionEvaluator.shouldSkip(ConditionEvaluator.java:108) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsForBeanMethod(ConfigurationClassBeanDefinitionReader.java:181) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsForConfigurationClass(ConfigurationClassBeanDefinitionReader.java:141) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitions(ConfigurationClassBeanDefinitionReader.java:117) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:327) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:232) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:275) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:95) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:705) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:531) ~[spring-context-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142) ~[spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE] at com.example.zhang.cloud.ZhangGetewayApplication.main(ZhangGetewayApplication.java:17) [classes/:na] Caused by: java.lang.IllegalStateException: Failed to introspect Class [org.springframework.cloud.netflix.zuul.ZuulServerAutoConfiguration$ZuulMetricsConfiguration] from ClassLoader [sun.misc.Launcher$AppClassLoader@764c12b6] at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:507) ~[spring-core-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:404) ~[spring-core-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:389) ~[spring-core-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.util.ReflectionUtils.getUniqueDeclaredMethods(ReflectionUtils.java:447) ~[spring-core-5.1.7.RELEASE.jar:5.1.7.RELEASE] at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(Unknown Source) ~[na:1.8.0_101] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getTypeForFactoryMethod(AbstractAutowireCapableBeanFactory.java:738) ~[spring-beans-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineTargetType(AbstractAutowireCapableBeanFactory.java:679) ~[spring-beans-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:647) ~[spring-beans-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1518) ~[spring-beans-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1023) ~[spring-beans-5.1.7.RELEASE.jar:5.1.7.RELEASE] at org.springframework.boot.autoconfigure.condition.BeanTypeRegistry.addBeanTypeForNonAliasDefinition(BeanTypeRegistry.java:195) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.condition.BeanTypeRegistry.addBeanTypeForNonAliasDefinition(BeanTypeRegistry.java:159) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.condition.BeanTypeRegistry.addBeanType(BeanTypeRegistry.java:152) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.condition.BeanTypeRegistry.updateTypesIfNecessary(BeanTypeRegistry.java:140) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at java.util.Iterator.forEachRemaining(Unknown Source) ~[na:1.8.0_101] at org.springframework.boot.autoconfigure.condition.BeanTypeRegistry.updateTypesIfNecessary(BeanTypeRegistry.java:135) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.condition.BeanTypeRegistry.getNamesForType(BeanTypeRegistry.java:97) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.condition.OnBeanCondition.collectBeanNamesForType(OnBeanCondition.java:298) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.condition.OnBeanCondition.getBeanNamesForType(OnBeanCondition.java:289) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.condition.OnBeanCondition.getBeanNamesForType(OnBeanCondition.java:278) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.condition.OnBeanCondition.getMatchingBeans(OnBeanCondition.java:189) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.condition.OnBeanCondition.getMatchOutcome(OnBeanCondition.java:125) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.condition.SpringBootCondition.matches(SpringBootCondition.java:47) ~[spring-boot-autoconfigure-2.1.5.RELEASE.jar:2.1.5.RELEASE] ... 17 common frames omitted Caused by: java.lang.NoClassDefFoundError: com/netflix/zuul/monitoring/CounterFactory at java.lang.Class.getDeclaredMethods0(Native Method) ~[na:1.8.0_101] at java.lang.Class.privateGetDeclaredMethods(Unknown Source) ~[na:1.8.0_101] at java.lang.Class.getDeclaredMethods(Unknown Source) ~[na:1.8.0_101] at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:489) ~[spring-core-5.1.7.RELEASE.jar:5.1.7.RELEASE] ... 39 common frames omitted Caused by: java.lang.ClassNotFoundException: com.netflix.zuul.monitoring.CounterFactory at java.net.URLClassLoader.findClass(Unknown Source) ~[na:1.8.0_101] at java.lang.ClassLoader.loadClass(Unknown Source) ~[na:1.8.0_101] at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) ~[na:1.8.0_101] at java.lang.ClassLoader.loadClass(Unknown Source) ~[na:1.8.0_101] ... 43 common frames omitted springboot版本:2.1.5.RELEASE springcloud版本:Finchley.SR1 依赖: <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-zuul</artifactId> </dependency> 哪位大神能解答一下,谢谢啦
java.lang.OutOfMemory异常
各位大神,小生在做excel导出的时候遇见了这么一个问题,作为实习生实在是莫名其妙,求各位大神帮个小忙。 java.lang.OutOfMemoryError: GC overhead limit exceeded 16:31:22.700 [nioEventLoopGroup-2-8] WARN io.netty.channel.nio.NioEventLoop - Unexpected exception in the selector loop. java.lang.OutOfMemoryError: GC overhead limit exceeded at java.util.ArrayList.iterator(ArrayList.java:814) ~[na:1.7.0_80] at sun.nio.ch.WindowsSelectorImpl.updateSelectedKeys(WindowsSelectorImpl.java:496) ~[na:1.7.0_80] at sun.nio.ch.WindowsSelectorImpl.doSelect(WindowsSelectorImpl.java:172) ~[na:1.7.0_80] at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:87) ~[na:1.7.0_80] at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:98) ~[na:1.7.0_80] at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:622) ~[netty-transport-4.0.32.Final.jar:4.0.32.Final] at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:310) ~[netty-transport-4.0.32.Final.jar:4.0.32.Final] at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:112) [netty-common-4.0.32.Final.jar:4.0.32.Final] at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:137) [netty-common-4.0.32.Final.jar:4.0.32.Final] at java.lang.Thread.run(Thread.java:745) [na:1.7.0_80] 16:31:23.334 [Thread-6] ERROR o.a.e.i.a.AcquireTimerJobsRunnable - exception during timer job acquisition: GC overhead limit exceeded java.lang.OutOfMemoryError: GC overhead limit exceeded at java.util.Arrays.copyOf(Arrays.java:2367) ~[na:1.7.0_80] at java.lang.AbstractStringBuilder.expandCapacity(AbstractStringBuilder.java:130) ~[na:1.7.0_80] at java.lang.AbstractStringBuilder.ensureCapacityInternal(AbstractStringBuilder.java:114) ~[na:1.7.0_80] at java.lang.AbstractStringBuilder.append(AbstractStringBuilder.java:415) ~[na:1.7.0_80] at java.lang.StringBuilder.append(StringBuilder.java:132) ~[na:1.7.0_80] at org.apache.ibatis.reflection.wrapper.BeanWrapper.getBeanProperty(BeanWrapper.java:171) ~[mybatis-3.3.0.jar:3.3.0] at org.apache.ibatis.reflection.wrapper.BeanWrapper.get(BeanWrapper.java:49) ~[mybatis-3.3.0.jar:3.3.0] at org.apache.ibatis.reflection.MetaObject.getValue(MetaObject.java:122) ~[mybatis-3.3.0.jar:3.3.0] at org.apache.ibatis.executor.BaseExecutor.createCacheKey(BaseExecutor.java:212) ~[mybatis-3.3.0.jar:3.3.0] at org.apache.ibatis.executor.CachingExecutor.createCacheKey(CachingExecutor.java:139) ~[mybatis-3.3.0.jar:3.3.0] at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:81) ~[mybatis-3.3.0.jar:3.3.0] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:120) ~[mybatis-3.3.0.jar:3.3.0] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:113) ~[mybatis-3.3.0.jar:3.3.0] at org.activiti.engine.impl.db.DbSqlSession.selectListWithRawParameter(DbSqlSession.java:438) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.db.DbSqlSession.selectList(DbSqlSession.java:429) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.db.DbSqlSession.selectList(DbSqlSession.java:424) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.db.DbSqlSession.selectList(DbSqlSession.java:411) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.persistence.entity.JobEntityManager.findNextTimerJobsToExecute(JobEntityManager.java:157) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.cmd.AcquireTimerJobsCmd.execute(AcquireTimerJobsCmd.java:45) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.cmd.AcquireTimerJobsCmd.execute(AcquireTimerJobsCmd.java:29) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.interceptor.CommandInvoker.execute(CommandInvoker.java:24) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:57) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.spring.SpringTransactionInterceptor$1.doInTransaction(SpringTransactionInterceptor.java:47) ~[activiti-spring-5.19.0.2.jar:5.19.0.2] at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:133) ~[spring-tx-4.2.2.RELEASE.jar:4.2.2.RELEASE] at org.activiti.spring.SpringTransactionInterceptor.execute(SpringTransactionInterceptor.java:45) ~[activiti-spring-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:31) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:40) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:35) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at org.activiti.engine.impl.asyncexecutor.AcquireTimerJobsRunnable.run(AcquireTimerJobsRunnable.java:52) ~[activiti-engine-5.19.0.2.jar:5.19.0.2] at java.lang.Thread.run(Thread.java:745) [na:1.7.0_80] /report/collectionPaymentClass-report-down java.lang.OutOfMemoryError: GC overhead limit exceeded
java.lang.NoClassDefFoundError
![图片说明](https://img-ask.csdn.net/upload/201705/03/1493780867_650176.png) linux下使用jedis,运行目录如上图,Main.java内容: ``` import redis.clients.jedis.exceptions.*; import redis.clients.jedis.*; import redis.clients.util.*; import org.apache.commons.pool2.*; import org.apache.commons.pool2.proxy.*; import org.apache.commons.pool2.impl.*; public class Main{ public static void main(String[] args){ Jedis jedis = new Jedis("127.0.0.1",6379); jedis.set("s2","123"); String result = jedis.get("s2"); System.out.println(result); jedis.close(); } } ``` 进入该目录下执行 javac -cp jedis-2.7.0.jar:commons-pool2-2.3.jar: Main.java 编译成功,然后运行 java Main报错: Exception in thread "main" java.lang.NoClassDefFoundError: redis/clients/jedis/Jedis at Main.main(Main.java:20) Caused by: java.lang.ClassNotFoundException: redis.clients.jedis.Jedis at java.net.URLClassLoader$1.run(URLClassLoader.java:366) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:425) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ... 1 more 编译成功了,但是运行时却找不到类?还是说编译其实也有问题,在Main.java中已经把两个外部jar包的所有类都import了。查了网上不少资料了但是还是没解决,平常都用IDE的,这次试试用javac然后就这样了。求解答,谢谢。
Jmeter刚启动就报错,java.lang.StackOverflowError: null
* 刚启动就报错,反射错误?? ``` 2019-10-15 19:25:30,381 INFO o.j.r.JARSourceHTTP: Found cached repo 2019-10-15 19:25:30,490 INFO o.j.r.PluginManager: Plugins Status: [jpgc-graphs-basic=2.0, jpgc-graphs-additional=Extras, jpgc-autostop=Extras, jpgc-sense=Standard, jpgc-cmd=Standard, jpgc-graphs-composite=Standard, jpgc-csl=Standard, jpgc-functions=2.1, jpgc-casutg=2.7, jpgc-dbmon=Extras, jpgc-graphs-dist=Extras, jpgc-dummy=Standard, jpgc-filterresults=Standard, jpgc-ffw=Standard, jpgc-ggl=Extras, jpgc-httpraw=Extras, jpgc-sts=Extras, jpgc-fifo=Standard, jpgc-jmxmon=Extras, jpgc-graphs-vs=Extras, jpgc-lockfile=Extras, jpgc-mergeresults=Standard, jpgc-pde=Extras, jpgc-prmctl=Extras, jpgc-perfmon=Standard, jpgc-plugins-manager=1.3, jpgc-synthesis=Standard, jpgc-plancheck=Standard, jpgc-tst=Standard, jpgc-udp=Extras, jpgc-csvars=Extras, jpgc-wsc=Standard, jpgc-xml=Extras, jmeter-core=5.1, jmeter-ftp=5.1, jmeter-http=5.1, jmeter-jdbc=5.1, jmeter-jms=5.1, jmeter-junit=5.1, jmeter-java=5.1, jmeter-ldap=5.1, jmeter-mail=5.1, jmeter-mongodb=5.1, jmeter-native=5.1, jmeter-tcp=5.1, jmeter-components=5.1, jpgc-standard=2.0] 2019-10-15 19:25:30,490 INFO o.j.r.PluginManagerMenuItem: Plugins Manager has upgrades: [jpgc-casutg] 2019-10-15 19:25:30,928 WARN o.a.j.g.u.MenuFactory: Could not instantiate class: kg.apc.jmeter.reporters.LoadosophiaUploaderGui java.lang.reflect.InvocationTargetException: null at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_131] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[?:1.8.0_131] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:1.8.0_131] at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[?:1.8.0_131] at org.apache.jmeter.gui.util.MenuFactory.getGUIComponent(MenuFactory.java:174) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.gui.util.MenuFactory.initializeMenus(MenuFactory.java:141) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.gui.util.MenuFactory.<clinit>(MenuFactory.java:106) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.gui.TestPlanGui.createPopupMenu(TestPlanGui.java:92) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.gui.tree.JMeterTreeNode.createPopupMenu(JMeterTreeNode.java:185) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.gui.action.EditCommand.doAction(EditCommand.java:46) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.gui.action.ActionRouter.performAction(ActionRouter.java:88) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.gui.action.ActionRouter.lambda$actionPerformed$0(ActionRouter.java:70) ~[ApacheJMeter_core.jar:5.1 r1853635] at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311) [?:1.8.0_131] at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756) [?:1.8.0_131] at java.awt.EventQueue.access$500(EventQueue.java:97) [?:1.8.0_131] at java.awt.EventQueue$3.run(EventQueue.java:709) [?:1.8.0_131] at java.awt.EventQueue$3.run(EventQueue.java:703) [?:1.8.0_131] at java.security.AccessController.doPrivileged(Native Method) [?:1.8.0_131] at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80) [?:1.8.0_131] at java.awt.EventQueue.dispatchEvent(EventQueue.java:726) [?:1.8.0_131] at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201) [?:1.8.0_131] at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) [?:1.8.0_131] at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) [?:1.8.0_131] at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) [?:1.8.0_131] at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) [?:1.8.0_131] at java.awt.EventDispatchThread.run(EventDispatchThread.java:82) [?:1.8.0_131] Caused by: java.lang.NoClassDefFoundError: org/apache/commons/httpclient/methods/multipart/PartSource at kg.apc.jmeter.reporters.LoadosophiaUploaderGui.init(LoadosophiaUploaderGui.java:114) ~[JMeterPlugins-Standard.jar:?] at kg.apc.jmeter.reporters.LoadosophiaUploaderGui.<init>(LoadosophiaUploaderGui.java:28) ~[JMeterPlugins-Standard.jar:?] ... 26 more Caused by: java.lang.ClassNotFoundException: org.apache.commons.httpclient.methods.multipart.PartSource at java.net.URLClassLoader.findClass(URLClassLoader.java:381) ~[?:1.8.0_131] at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_131] at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_131] at kg.apc.jmeter.reporters.LoadosophiaUploaderGui.init(LoadosophiaUploaderGui.java:114) ~[JMeterPlugins-Standard.jar:?] at kg.apc.jmeter.reporters.LoadosophiaUploaderGui.<init>(LoadosophiaUploaderGui.java:28) ~[JMeterPlugins-Standard.jar:?] ... 26 more ```’ * 接着启动线程,又报错StackOverflowError, ``` 2019-10-15 19:25:44,875 INFO o.a.j.t.JMeterThread: Thread started: 线程组 2-1 2019-10-15 19:25:44,876 INFO o.a.j.t.JMeterThread: Thread is done: 线程组 2-1 2019-10-15 19:25:44,876 INFO o.a.j.t.JMeterThread: Thread finished: 线程组 2-1 2019-10-15 19:25:45,703 INFO o.a.j.t.JMeterThread: Thread started: jp@gc - Stepping Thread Group (deprecated) 1-2 2019-10-15 19:25:46,703 INFO o.a.j.t.JMeterThread: Thread started: jp@gc - Stepping Thread Group (deprecated) 1-3 2019-10-15 19:25:47,696 INFO o.a.j.t.JMeterThread: Thread started: jp@gc - Stepping Thread Group (deprecated) 1-4 2019-10-15 19:25:48,195 INFO o.a.j.t.JMeterThread: Thread finished: jp@gc - Stepping Thread Group (deprecated) 1-1 2019-10-15 19:25:48,196 ERROR o.a.j.JMeter: Uncaught exception: java.lang.StackOverflowError: null at org.apache.jmeter.testelement.AbstractTestElement.recoverRunningVersion(AbstractTestElement.java:514) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.testelement.property.TestElementProperty.recoverRunningVersion(TestElementProperty.java:125) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.testelement.property.MultiProperty.recoverRunningVersionOfSubElements(MultiProperty.java:75) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.testelement.property.CollectionProperty.recoverRunningVersion(CollectionProperty.java:205) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.testelement.AbstractTestElement.recoverRunningVersion(AbstractTestElement.java:514) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.testelement.property.TestElementProperty.recoverRunningVersion(TestElementProperty.java:125) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.testelement.AbstractTestElement.recoverRunningVersion(AbstractTestElement.java:514) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.threads.JMeterThread.notifyTestListeners(JMeterThread.java:973) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.threads.JMeterThread$IterationListener.iterationStart(JMeterThread.java:1054) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.fireIterationStart(GenericController.java:399) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.fireIterEvents(GenericController.java:391) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.next(GenericController.java:160) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.LoopController.next(LoopController.java:135) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.LoopController.nextIsNull(LoopController.java:167) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.next(GenericController.java:170) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.LoopController.next(LoopController.java:135) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.nextIsAController(GenericController.java:225) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.next(GenericController.java:175) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.LoopController.next(LoopController.java:135) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.LoopController.nextIsNull(LoopController.java:167) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.next(GenericController.java:170) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.LoopController.next(LoopController.java:135) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.nextIsAController(GenericController.java:225) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.next(GenericController.java:175) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.LoopController.next(LoopController.java:135) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.LoopController.nextIsNull(LoopController.java:167) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.next(GenericController.java:170) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.LoopController.next(LoopController.java:135) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.nextIsAController(GenericController.java:225) ~[ApacheJMeter_core.jar:5.1 r1853635] at org.apache.jmeter.control.GenericController.next(GenericController.java:175) ~[ApacheJMeter_core.jar:5.1 r1853635] ``` 前辈们帮忙看看
修改java.lang.String类时出错?
本人想修改java.lang.String类,然后导出成jar,代替原来虚拟机的String类使用,但是在添加一个布尔数组后,导出成jar并使用时出现下面的错误: Error occurred during initialization of VM java.lang.ExceptionInInitializerError Caused by: java.lang.IllegalArgumentException: name can't be empty at java.security.BasicPermission.init(Unknown Source) at java.security.BasicPermission.<init>(Unknown Source) at java.lang.RuntimePermission.<init>(Unknown Source) at java.lang.Thread.<clinit>(Unknown Source) 添加的数组形式如下: private boolean barray[]; 如果改成private boolean barray; 则可正确运行。 如果改成跟String源码中的value一样:private final char value[]; 也不行。 百思不得其解,有人知道是怎么回事么?
java.lang.RuntimeException: Invalid action class configuration ....
项目开发中遇见以下问题: java.lang.RuntimeException: Invalid action class configuration that references an unknown class named [com.zhaod555.talent.action.TResumeAppReplyAction] at org.apache.struts2.convention.ConventionsServiceImpl.determineResultPath(ConventionsServiceImpl.java:99) [struts2-convention-plugin-2.1.6.jar:na] at org.apache.struts2.convention.ConventionUnknownHandler.determinePath(ConventionUnknownHandler.java:379) [struts2-convention-plugin-2.1.6.jar:na] at org.apache.struts2.convention.ConventionUnknownHandler.handleUnknownResult(ConventionUnknownHandler.java:268) [struts2-convention-plugin-2.1.6.jar:na] at com.opensymphony.xwork2.DefaultUnknownHandlerManager.handleUnknownResult(DefaultUnknownHandlerManager.java:76) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.createResult(DefaultActionInvocation.java:214) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:355) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:265) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:163) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:249) [xwork-2.1.2.jar:na] at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68) [struts2-core-2.1.6.jar:na] at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:148) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:93) [struts2-core-2.1.6.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235) [struts2-core-2.1.6.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:128) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at org.apache.struts2.interceptor.ProfilingActivationInterceptor.intercept(ProfilingActivationInterceptor.java:104) [struts2-core-2.1.6.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267) [struts2-core-2.1.6.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:148) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164) [struts2-core-2.1.6.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:128) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176) [xwork-2.1.2.jar:na] at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) [xwork-2.1.2.jar:na] at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52) [struts2-core-2.1.6.jar:na] at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:468) [struts2-core-2.1.6.jar:na] at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77) [struts2-core-2.1.6.jar:na] at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:76) [struts2-core-2.1.6.jar:na] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) [catalina.jar:na] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:na] at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198) [spring-orm-2.5.6.jar:2.5.6] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) [spring-web-2.5.6.jar:2.5.6] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) [catalina.jar:na] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:na] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96) [spring-web-2.5.6.jar:2.5.6] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) [spring-web-2.5.6.jar:2.5.6] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) [catalina.jar:na] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:na] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) [catalina.jar:na] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) [catalina.jar:na] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128) [catalina.jar:na] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [catalina.jar:na] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [catalina.jar:na] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286) [catalina.jar:na] at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845) [tomcat-coyote.jar:na] at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583) [tomcat-coyote.jar:na] at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) [tomcat-coyote.jar:na] at java.lang.Thread.run(Thread.java:619) [na:1.6.0_14] Caused by: java.lang.ClassNotFoundException: com.zhaod555.talent.action.TResumeAppReplyAction at java.net.URLClassLoader$1.run(URLClassLoader.java:200) [na:1.6.0_14] at java.security.AccessController.doPrivileged(Native Method) [na:1.6.0_14] at java.net.URLClassLoader.findClass(URLClassLoader.java:188) [na:1.6.0_14] at java.lang.ClassLoader.loadClass(ClassLoader.java:307) [na:1.6.0_14] at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) [na:1.6.0_14] at java.lang.ClassLoader.loadClass(ClassLoader.java:252) [na:1.6.0_14] at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320) [na:1.6.0_14] at java.lang.Class.forName0(Native Method) [na:1.6.0_14] at java.lang.Class.forName(Class.java:169) [na:1.6.0_14] at org.apache.struts2.convention.ConventionsServiceImpl.determineResultPath(ConventionsServiceImpl.java:97) [struts2-convention-plugin-2.1.6.jar:na] ... 72 common frames omitted 网上有人说: It is caused because the plugin JAR is loaded by the extension classloader and the actions are loaded by the WAR classloader. ConventionServiceImpl.determineResultPath simply uses Class.forName rather than checking the context classloader. So it fails to find the action--even though the action class is already loaded on the WAR classloader. 但我还是不知道怎么办,请高手们指点,非常谢谢了
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java.lang.reflect.InvocationTargetException: null
java.lang.reflect.InvocationTargetException: null at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_77] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_77] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_77] at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_77] at org.apache.cxf.bus.extension.Extension.load(Extension.java:249) ~[cxf-core-3.1.5.jar:3.1.5] at org.apache.cxf.bus.extension.ExtensionManagerImpl.loadAndRegister(ExtensionManagerImpl.java:213) [cxf-core-3.1.5.jar:3.1.5] at org.apache.cxf.bus.extension.ExtensionManagerImpl.getBeansOfType(ExtensionManagerImpl.java:348) [cxf-core-3.1.5.jar:3.1.5] at org.apache.cxf.bus.spring.SpringBeanLocator.getBeansOfType(SpringBeanLocator.java:153) [cxf-core-3.1.5.jar:3.1.5] at org.apache.cxf.bus.extension.ExtensionManagerBus.getExtension(ExtensionManagerBus.java:220) [cxf-core-3.1.5.jar:3.1.5] at org.apache.cxf.transport.http.HTTPTransportFactory.getDestination(HTTPTransportFactory.java:262) [cxf-rt-transports-http-3.1.5.jar:3.1.5] at org.apache.cxf.binding.soap.SoapTransportFactory.getDestination(SoapTransportFactory.java:131) [cxf-rt-bindings-soap-3.1.5.jar:3.1.5] at org.apache.cxf.endpoint.ServerImpl.initDestination(ServerImpl.java:84) [cxf-core-3.1.5.jar:3.1.5] at org.apache.cxf.endpoint.ServerImpl.<init>(ServerImpl.java:63) [cxf-core-3.1.5.jar:3.1.5] at org.apache.cxf.frontend.ServerFactoryBean.create(ServerFactoryBean.java:179) [cxf-rt-frontend-simple-3.1.5.jar:3.1.5] at org.apache.cxf.jaxws.JaxWsServerFactoryBean.create(JaxWsServerFactoryBean.java:211) [cxf-rt-frontend-jaxws-3.1.5.jar:3.1.5] at org.apache.cxf.jaxws.spring.NamespaceHandler$SpringServerFactoryBean.create(NamespaceHandler.java:60) [cxf-rt-frontend-jaxws-3.1.5.jar:3.1.5] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_77] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_77] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_77] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_77] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeCustomInitMethod(AbstractAutowireCapableBeanFactory.java:1706) [spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1645) [spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574) [spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545) [spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) [spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) [spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) [spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) [spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) [spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772) [spring-beans-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:839) [spring-context-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:538) [spring-context-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:446) [spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:328) [spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:107) [spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE] at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4811) [catalina.jar:8.0.33] at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5251) [catalina.jar:8.0.33] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:147) [catalina.jar:8.0.33] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1408) [catalina.jar:8.0.33] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1398) [catalina.jar:8.0.33] at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_77] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_77] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_77] at java.lang.Thread.run(Thread.java:745) [na:1.8.0_77] Caused by: java.lang.NoClassDefFoundError: io/netty/util/Version at org.apache.cxf.transport.http.netty.server.NettyHttpDestinationFactory.<init>(NettyHttpDestinationFactory.java:36) ~[cxf-rt-transports-http-netty-server-3.1.5.jar:3.1.5] ... 44 common frames omitted Caused by: java.lang.ClassNotFoundException: io.netty.util.Version at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1305) ~[catalina.jar:8.0.33] at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1139) ~[catalina.jar:8.0.33] ... 45 common frames omitted
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