环境变量配置jdk1.8 yjb@user:~/IdeaProjects/First$ java -version java version "1.8.0_73" Java(TM) SE Runtime Environment (build 1.8.0_73-b02) Java HotSpot(TM) 64-Bit Server VM (build 25.73-b02, mixed mode) yjb@user:~/IdeaProjects/First$ 通过命令行可以运行程序，但是在idea下运行出现unsupported major.minor version 52.0 /home/yjb/Sofware/jdk1.8.0_73/bin/java -Didea.launcher.port=7532 -Didea.launcher.bin.path=/home/yjb/Sofware/idea-IC-162.1121.32/bin -Dfile.encoding=UTF-8 -classpath /home/yjb/Sofware/jdk1.8.0_73/jre/lib/charsets.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/deploy.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/ext/cldrdata.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/ext/dnsns.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/ext/jaccess.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/ext/jfxrt.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/ext/localedata.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/ext/nashorn.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/ext/sunec.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/ext/sunjce_provider.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/ext/sunpkcs11.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/ext/zipfs.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/javaws.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/jce.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/jfr.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/jfxswt.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/jsse.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/management-agent.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/plugin.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/resources.jar:/home/yjb/Sofware/jdk1.8.0_73/jre/lib/rt.jar:/home/yjb/IdeaProjects/First/out/production/First:/home/yjb/IdeaProjects/First/tmVar333.jar:/home/yjb/IdeaProjects/First/tmVar.jar:/home/yjb/IdeaProjects/First/tmVar22.jar:/home/yjb/IdeaProjects/First/GNormPlus.jar:/home/yjb/IdeaProjects/First/tmVarJava.jar:/home/yjb/Sofware/idea-IC-162.1121.32/lib/idea_rt.jar com.intellij.rt.execution.application.AppMain Try null Exception in thread "main" java.lang.UnsupportedClassVersionError: tmVarlib/tmVar : Unsupported major.minor version 52.0 null at java.lang.ClassLoader.defineClass1(Native Method) null at java.lang.ClassLoader.defineClass(ClassLoader.java:803) null at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) null at java.net.URLClassLoader.defineClass(URLClassLoader.java:449) null at java.net.URLClassLoader.access$100(URLClassLoader.java:71) null at java.net.URLClassLoader$1.run(URLClassLoader.java:361) null at java.net.URLClassLoader$1.run(URLClassLoader.java:355) null at java.security.AccessController.doPrivileged(Native Method) null at java.net.URLClassLoader.findClass(URLClassLoader.java:354) null at java.lang.ClassLoader.loadClass(ClassLoader.java:425) null at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) null at java.lang.ClassLoader.loadClass(ClassLoader.java:358) null at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:482) end error!!!!!!!!!!!!!

我把eclipse换成jdk1.6，系统环境换成jdk1.6但是maven打包时 还是报下面的错误，求大神指导 Exception in thread "main" java.lang.UnsupportedClassVersionError: org/apache/maven/cli/MavenCli : Unsupported major.minor version 51.0 at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631) at java.lang.ClassLoader.defineClass(ClassLoader.java:615) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141) at java.net.URLClassLoader.defineClass(URLClassLoader.java:283) at java.net.URLClassLoader.access$000(URLClassLoader.java:58) at java.net.URLClassLoader$1.run(URLClassLoader.java:197) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:190) at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClassFromSelf(ClassRealm.java:401) at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:42) at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271) at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:254) at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239) at org.codehaus.plexus.classworlds.launcher.Launcher.getMainClass(Launcher.java:144) at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:266) at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229) at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415) at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356) at org.codehaus.classworlds.Launcher.main(Launcher.java:47)

项目可以正常启动，登录界面也可以展示，但是点击登录按钮的时候， 项目报错，debug也不进，查看了一下jdk版本，都是1.7的，求助，搞半天了。。。    

SEVERE: Servlet.service() for servlet [springMVC] in context with path [/Apple] threw exception [Request processing failed; nested exception is org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot load JDBC driver class 'com.mysql.cj.jdbc.Driver' ### The error may exist in file [D:\Users\Administrator\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\Apple\WEB-INF\classes\com\jc\mapper\UserMapper.xml] ### The error may involve com.jc.dao.UserDao.getRow ### The error occurred while executing a query ### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot load JDBC driver class 'com.mysql.cj.jdbc.Driver'] with root cause java.lang.UnsupportedClassVersionError: com/mysql/cj/jdbc/Driver : Unsupported major.minor version 52.0 (unable to load class com.mysql.cj.jdbc.Driver) at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2961) at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1210) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1690) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1571) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Unknown Source) at org.apache.commons.dbcp.BasicDataSource.createConnectionFactory(BasicDataSource.java:1415) at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1371) at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044) at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111) at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77) at org.mybatis.spring.transaction.SpringManagedTransaction.openConnection(SpringManagedTransaction.java:81) at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:67) at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:315) at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:75) at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:61) at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:303) at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:154) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:102) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:82) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:120) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:113) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:73) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:358) at $Proxy11.selectOne(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.selectOne(SqlSessionTemplate.java:163) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:69) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:53) at $Proxy12.getRow(Unknown Source) at com.jc.service.UserService.login(UserService.java:19) at com.jc.controller.UserController.login(UserController.java:25) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:781) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:721) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:943) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:868) at javax.servlet.http.HttpServlet.service(HttpServlet.java:646) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842) at javax.servlet.http.HttpServlet.service(HttpServlet.java:727) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1074) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Unknown Source)

用myEclipse2015 stable2.0出现的问题。JDK是最新的。环境变量也设置过了。但是一打开就出现这个。SDK也是下的最新的。 installed JREs设置里也已经改过JDK的位置了。 compiler里也改成1.8了 JDK是jdk1.8.0_92的。 Parsing Data for android-N failed Unsupported major.minor version 52.0 大神帮帮忙！

最近研究Mapreduce，准备在Myeclipse上装一个hadoop插件，把hadoop-eclipse-plugin-2.2.0.jar放在dropins目录下后，打开preferences可以看见Hadoop Map/Rreduce这一项，但是当我点击这项时报错：org/apache/hadoop/eclipse/preferences/MapReducePreferencePage : Unsupported major.minor version 51.0，我把JDK从1.7改为1.6还是报同样的错误，不知道是什么原因，求大神指导！

我所知道的是前台用ajax实现，然后后台增加，有没有更好的性能更好的实现呢？

06-Dec-2019 23:49:29.923 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployWAR Deploying web application archive [E:\apache-tomcat-8.5.34\webapps\demo-0.0.1-SNAPSHOT.war] 06-Dec-2019 23:49:31.682 严重 [localhost-startStop-1] org.apache.catalina.core.ContainerBase.addChildInternal ContainerBase.addChild: start: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/demo-0.0.1-SNAPSHOT]] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:167) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:754) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:730) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:734) at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:985) at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1857) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) at java.util.concurrent.FutureTask.run(FutureTask.java:262) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) Caused by: java.lang.UnsupportedClassVersionError: org/springframework/web/SpringServletContainerInitializer : Unsupported major.minor version 52.0 (unable to load class [org.springframework.web.SpringServletContainerInitializer]) at org.apache.catalina.loader.WebappClassLoaderBase.findClassInternal(WebappClassLoaderBase.java:2340) at org.apache.catalina.loader.WebappClassLoaderBase.findClass(WebappClassLoaderBase.java:829) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1278) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1137) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:278) at org.apache.catalina.startup.WebappServiceLoader.loadServices(WebappServiceLoader.java:188) at org.apache.catalina.startup.WebappServiceLoader.load(WebappServiceLoader.java:159) at org.apache.catalina.startup.ContextConfig.processServletContainerInitializers(ContextConfig.java:1612) at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1125) at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:765) at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:299) at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:94) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5154) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) ... 10 more 06-Dec-2019 23:49:31.688 严重 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployWAR Error deploying web application archive [E:\apache-tomcat-8.5.34\webapps\demo-0.0.1-SNAPSHOT.war] java.lang.IllegalStateException: ContainerBase.addChild: start: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/demo-0.0.1-SNAPSHOT]] at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:758) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:730) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:734) at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:985) at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1857) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) at java.util.concurrent.FutureTask.run(FutureTask.java:262) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745)

jdk版本是1.8的，sqljdbc4，能兼容sql2012的，一切都是按照网上教程来的，但是还是会报错， Exception in thread "main" java.lang.UnsupportedClassVersionError: com/microsoft/sqlserver/jdbc/SQLServerDriver : Unsupported major.minor version 52.0 at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:800) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) at java.net.URLClassLoader.defineClass(URLClassLoader.java:449) at java.net.URLClassLoader.access$100(URLClassLoader.java:71) at java.net.URLClassLoader$1.run(URLClassLoader.java:361) 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) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:190) at com.util.DB.main(DB.java:14) 麻烦帮我看看

Maven clean 出现如下报错是什么原因 Exception in thread "main" java.lang.NoClassDefFoundError: com/google/common/util/concurrent/internal/InternalFutureFailureAccess at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:763) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) at java.net.URLClassLoader.defineClass(URLClassLoader.java:467) at java.net.URLClassLoader.access$100(URLClassLoader.java:73) at java.net.URLClassLoader$1.run(URLClassLoader.java:368) at java.net.URLClassLoader$1.run(URLClassLoader.java:362) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:361) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:763) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) at java.net.URLClassLoader.defineClass(URLClassLoader.java:467) at java.net.URLClassLoader.access$100(URLClassLoader.java:73) at java.net.URLClassLoader$1.run(URLClassLoader.java:368) at java.net.URLClassLoader$1.run(URLClassLoader.java:362) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:361) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:763) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) at java.net.URLClassLoader.defineClass(URLClassLoader.java:467) at java.net.URLClassLoader.access$100(URLClassLoader.java:73) at java.net.URLClassLoader$1.run(URLClassLoader.java:368) at java.net.URLClassLoader$1.run(URLClassLoader.java:362) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:361) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at com.google.common.cache.LocalCache$LoadingValueReference.<init>(LocalCache.java:3472) at com.google.common.cache.LocalCache$LoadingValueReference.<init>(LocalCache.java:3476) at com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2134) at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2045) at com.google.common.cache.LocalCache.get(LocalCache.java:3953) at com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:3976) at com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4960) at com.google.common.cache.LocalCache$LocalLoadingCache.getUnchecked(LocalCache.java:4966) at com.google.inject.internal.Annotations$AnnotationChecker.hasAnnotations(Annotations.java:248) at com.google.inject.internal.Annotations.isBindingAnnotation(Annotations.java:314) at com.google.inject.Key.ensureIsBindingAnnotation(Key.java:402) at com.google.inject.Key.strategyFor(Key.java:389) at com.google.inject.Key.get(Key.java:251) at org.eclipse.sisu.wire.ParameterKeys.<clinit>(ParameterKeys.java:28) at org.eclipse.sisu.wire.DependencyAnalyzer.<init>(DependencyAnalyzer.java:93) at org.eclipse.sisu.wire.ElementAnalyzer.<init>(ElementAnalyzer.java:104) at org.eclipse.sisu.wire.WireModule.configure(WireModule.java:74) at com.google.inject.spi.Elements$RecordingBinder.install(Elements.java:340) at com.google.inject.spi.Elements.getElements(Elements.java:110) at com.google.inject.internal.InjectorShell$Builder.build(InjectorShell.java:138) at com.google.inject.internal.InternalInjectorCreator.build(InternalInjectorCreator.java:104) at com.google.inject.Guice.createInjector(Guice.java:96) at com.google.inject.Guice.createInjector(Guice.java:73) at com.google.inject.Guice.createInjector(Guice.java:62) at org.codehaus.plexus.DefaultPlexusContainer.addPlexusInjector(DefaultPlexusContainer.java:481) at org.codehaus.plexus.DefaultPlexusContainer.<init>(DefaultPlexusContainer.java:206) at org.apache.maven.cli.MavenCli.container(MavenCli.java:637) at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:283) at org.apache.maven.cli.MavenCli.main(MavenCli.java:194) 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.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289) at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229) at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415) at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356) Caused by: java.lang.ClassNotFoundException: com.google.common.util.concurrent.internal.InternalFutureFailureAccess at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ... 70 more

myeclipse运行一个简单的JavaProject时出现了下面的异常： Exception in thread "main" java.lang.UnsupportedClassVersionError: org/hiber nate/cfg/Configuration : Unsupported major.minor version 52.0 at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(Unknown Source) at java.security.SecureClassLoader.defineClass(Unknown Source) at java.net.URLClassLoader.defineClass(Unknown Source) at java.net.URLClassLoader.access$100(Unknown Source) at java.net.URLClassLoader$1.run(Unknown Source) at java.net.URLClassLoader$1.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at com.jxk.hibernate.Base.main(Base.java:13) 怎么解决啊啊

用redmine-java-api-3.0.0.jar，点运行弹出框A Java Exception has occurred 点确定后 出现.UnsupportedClassVersionError: com/taskadapter/redmineapi/RedmineException : Unsupported major.minor version 52.0

[CONSOLE] 2017-10-23 21:27:54,530 - org.springframework.web.context.ContextLoader -1 [localhost-startStop-1] ERROR org.springframework.web.context.ContextLoader - Context initialization failed org.springframework.beans.factory.CannotLoadBeanClassException: Error loading class [com.media.controller.UserController] for bean with name 'userController' defined in file [C:\Program Files\Apache Software Foundation\Tomcat 7.0\wtpwebapps\editor\WEB-INF\classes\com\media\controller\UserController.class]: problem with class file or dependent class; nested exception is java.lang.UnsupportedClassVersionError: com/media/controller/UserController : Unsupported major.minor version 52.0 (unable to load class com.media.controller.UserController) at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1330) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:594) at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1396) at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:959) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:683) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482) at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5118) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5634) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:899) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:875) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:652) at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:679) at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1966) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334) at java.util.concurrent.FutureTask.run(FutureTask.java:166) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:722) Caused by: java.lang.UnsupportedClassVersionError: com/media/controller/UserController : Unsupported major.minor version 52.0 (unable to load class com.media.controller.UserController) at org.apache.catalina.loader.WebappClassLoaderBase.findClassInternal(WebappClassLoaderBase.java:3200) at org.apache.catalina.loader.WebappClassLoaderBase.findClass(WebappClassLoaderBase.java:1373) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1861) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1735) at org.springframework.util.ClassUtils.forName(ClassUtils.java:247) at org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:395) at org.springframework.beans.factory.support.AbstractBeanFactory.doResolveBeanClass(AbstractBeanFactory.java:1348) at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1319) ... 23 more 十月 23, 2017 9:27:54 下午 org.apache.catalina.core.StandardContext listenerStart SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener org.springframework.beans.factory.CannotLoadBeanClassException: Error loading class [com.media.controller.UserController] for bean with name 'userController' defined in file [C:\Program Files\Apache Software Foundation\Tomcat 7.0\wtpwebapps\editor\WEB-INF\classes\com\media\controller\UserController.class]: problem with class file or dependent class; nested exception is java.lang.UnsupportedClassVersionError: com/media/controller/UserController : Unsupported major.minor version 52.0 (unable to load class com.media.controller.UserController) at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1330) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:594) at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1396) at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:959) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:683) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482) at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5118) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5634) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:899) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:875) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:652) at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:679) at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1966) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334) at java.util.concurrent.FutureTask.run(FutureTask.java:166) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:722) Caused by: java.lang.UnsupportedClassVersionError: com/media/controller/UserController : Unsupported major.minor version 52.0 (unable to load class com.media.controller.UserController) at org.apache.catalina.loader.WebappClassLoaderBase.findClassInternal(WebappClassLoaderBase.java:3200) at org.apache.catalina.loader.WebappClassLoaderBase.findClass(WebappClassLoaderBase.java:1373) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1861) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1735) at org.springframework.util.ClassUtils.forName(ClassUtils.java:247) at org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:395) at org.springframework.beans.factory.support.AbstractBeanFactory.doResolveBeanClass(AbstractBeanFactory.java:1348) at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1319) ... 23 more


目前服务器上已经部署了Tomcat7.0，我需要在上面再部署一个Tomcat8.0，具体怎么部署。（求详细部署步骤）

从svn上down下来的源码，在搭建本机环境的时候报错 ``` Exception in thread "main" java.lang.UnsupportedClassVersionError: org/apdplat/word/analysis/TextSimilarity : Unsupported major.minor version 52.0 2 at java.lang.ClassLoader.defineClass1(Native Method) 3 at java.lang.ClassLoader.defineClass(Unknown Source) 4 at java.security.SecureClassLoader.defineClass(Unknown Source) 5 at java.net.URLClassLoader.defineClass(Unknown Source) 6 at java.net.URLClassLoader.access$100(Unknown Source) 7 at java.net.URLClassLoader$1.run(Unknown Source) 8 at java.net.URLClassLoader$1.run(Unknown Source) 9 at java.security.AccessController.doPrivileged(Native Method) 10 at java.net.URLClassLoader.findClass(Unknown Source) 11 at java.lang.ClassLoader.loadClass(Unknown Source) 12 at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) 13 at java.lang.ClassLoader.loadClass(Unknown Source) 14 at com.platform.config.run.JfinalConfig.afterJFinalStart(JfinalConfig.java:184) 15 at com.jfinal.core.JFinalFilter.init(JFinalFilter.java:55) 16 at org.eclipse.jetty.servlet.FilterHolder.doStart(FilterHolder.java:119) 17 at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64) 18 at org.eclipse.jetty.servlet.ServletHandler.initialize(ServletHandler.java:724) 19 at org.eclipse.jetty.servlet.ServletContextHandler.startContext(ServletContextHandler.java:265) 20 at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1250) 21 at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:706) 22 at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:492) 23 at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64) 24 at org.eclipse.jetty.server.handler.HandlerWrapper.doStart(HandlerWrapper.java:95) 25 at org.eclipse.jetty.server.Server.doStart(Server.java:277) 26 at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64) 27 at com.jfinal.server.JettyServer.doStart(JettyServer.java:135) 28 at com.jfinal.server.JettyServer.start(JettyServer.java:67) 29 at com.jfinal.core.JFinal.start(JFinal.java:154) 30 at com.platform.config.run.JfinalConfig.main(JfinalConfig.java:210) ``` 在各种网站上查阅了一下，说是用低版本的JDK编译高版本的.class就会报这个错，有以下两种易发生的情况： 1，命令行输入java -version和javac -version发现版本不一致，修改之； 2，版本一致则检查Path路径，一般安装oracle的机子配置jdk的时候会覆盖路径，修改之。 但是！ 一，我没有装Oracle； Path路径为： d:\data\mblog\graphicsmagick-1.3.23-q8; C:\Windows\system32; C:\Windows; C:\Windows\System32\Wbem; C:\Windows\System32\WindowsPowerShell\v1.0\; D:\jdk1.7\bin; D:\jdk1.7\jre\bin; D:\mysqlinstallation\MySQL Utilities 1.3.6\; D:\maven\apache-maven-3.3.9\bin; 二，javac -version 下是java version “1.7.0_13” java -version下是 javac 1.7.0_13 所以，现在问题会出现在哪儿呢？ 我使用的是eclipse，jfinal，maven

java web项目部署之后，运行几天会不正常，登录页面可以打开，但是进行任何数据库操作都会特别卡，比如登录。 查了tomcat日志，宕机前只有一个MySQLSyntaxErrorException错误 大神分析一下 还有没有需要提供的东西？？ 用的是java,tomcat7,springmvc,spring3.0,hibernate,mysql

在网上好了很多的问题 都没有解决，针对web，大家用的都是的在tomcat下的lib里添加mysql-connector的jar包 但是还是没有解决 还是连接不上，也在url里面添加后缀了 package jdbc; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; import java.sql.Statement; public class JDBCDemo { private static final String URL="jdbc:mysql://localhost:3306/db4?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=Hongkong"; private static final String USERNAME="root"; private static final String PWD="root"; public static void update() {//增删改 Connection connection=null; Statement stmt =null; try { //导入驱动，加载具体驱动类 Class.forName("com.mysql.cj.jdbc.Driver");//加载具体的驱动类 //与数据库建立连接 connection=DriverManager.getConnection(URL,USERNAME,PWD); //增删改 stmt = connection.createStatement(); String sql="insert into student values(4,'kxk','123')"; int result = stmt.executeUpdate(sql); //处理结果：显示受影响行数 System.out.println(result); }catch (ClassNotFoundException e) { e.printStackTrace(); }catch (Exception e) { e.printStackTrace(); }finally { if(stmt!=null) { try { stmt.close(); }catch (SQLException e) { e.printStackTrace(); } } if(connection!=null) { try { connection.close(); }catch (SQLException e) { e.printStackTrace(); } } } } public static void main(String[] args) { update(); } } 报错还是 java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:338) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:264) 不知道哪里出现了问题，求助

[2015-06-21 09:40:53 - HellowWord] F:\eclipse 32\workspace\HellowWord\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:40:53 - HellowWord] [2015-06-21 09:40:53 - HellowWord] F:\eclipse 32\workspace\HellowWord\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:40:53 - HellowWord] [2015-06-21 09:40:53 - HellowWord] F:\eclipse 32\workspace\HellowWord\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 09:40:53 - HellowWord] [2015-06-21 09:40:55 - HellowWord] F:\eclipse 32\workspace\HellowWord\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:40:55 - HellowWord] [2015-06-21 09:40:55 - HellowWord] F:\eclipse 32\workspace\HellowWord\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:40:55 - HellowWord] [2015-06-21 09:40:55 - HellowWord] F:\eclipse 32\workspace\HellowWord\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 09:40:55 - HellowWord] [2015-06-21 09:41:00 - HellowWord] F:\eclipse 32\workspace\HellowWord\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:41:00 - HellowWord] [2015-06-21 09:41:00 - HellowWord] F:\eclipse 32\workspace\HellowWord\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:41:00 - HellowWord] [2015-06-21 09:41:00 - HellowWord] F:\eclipse 32\workspace\HellowWord\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 09:41:00 - HellowWord] [2015-06-21 09:54:11 - HellowAndroid] F:\eclipse 32\workspace\HellowAndroid\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:54:11 - HellowAndroid] [2015-06-21 09:54:11 - HellowAndroid] F:\eclipse 32\workspace\HellowAndroid\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:54:11 - HellowAndroid] [2015-06-21 09:54:11 - HellowAndroid] F:\eclipse 32\workspace\HellowAndroid\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 09:54:11 - HellowAndroid] [2015-06-21 09:54:13 - HellowAndroid] F:\eclipse 32\workspace\HellowAndroid\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:54:13 - HellowAndroid] [2015-06-21 09:54:13 - HellowAndroid] F:\eclipse 32\workspace\HellowAndroid\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:54:13 - HellowAndroid] [2015-06-21 09:54:13 - HellowAndroid] F:\eclipse 32\workspace\HellowAndroid\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 09:54:13 - HellowAndroid] [2015-06-21 09:54:14 - HellowAndroid] F:\eclipse 32\workspace\HellowAndroid\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:54:14 - HellowAndroid] [2015-06-21 09:54:14 - HellowAndroid] F:\eclipse 32\workspace\HellowAndroid\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 09:54:14 - HellowAndroid] [2015-06-21 09:54:14 - HellowAndroid] F:\eclipse 32\workspace\HellowAndroid\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 09:54:14 - HellowAndroid] [2015-06-21 10:11:03 - HellowWorld] F:\eclipse 32\workspace\HellowWorld\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:11:03 - HellowWorld] [2015-06-21 10:11:03 - HellowWorld] F:\eclipse 32\workspace\HellowWorld\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:11:03 - HellowWorld] [2015-06-21 10:11:03 - HellowWorld] F:\eclipse 32\workspace\HellowWorld\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 10:11:03 - HellowWorld] [2015-06-21 10:11:04 - HellowWorld] F:\eclipse 32\workspace\HellowWorld\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:11:04 - HellowWorld] [2015-06-21 10:11:04 - HellowWorld] F:\eclipse 32\workspace\HellowWorld\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:11:04 - HellowWorld] [2015-06-21 10:11:04 - HellowWorld] F:\eclipse 32\workspace\HellowWorld\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 10:11:04 - HellowWorld] [2015-06-21 10:11:05 - HellowWorld] F:\eclipse 32\workspace\HellowWorld\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:11:05 - HellowWorld] [2015-06-21 10:11:05 - HellowWorld] F:\eclipse 32\workspace\HellowWorld\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:11:05 - HellowWorld] [2015-06-21 10:11:05 - HellowWorld] F:\eclipse 32\workspace\HellowWorld\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 10:11:05 - HellowWorld] [2015-06-21 10:46:52 - HellowWorld1] F:\eclipse 32\workspace\HellowWorld1\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:46:52 - HellowWorld1] [2015-06-21 10:46:52 - HellowWorld1] F:\eclipse 32\workspace\HellowWorld1\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:46:52 - HellowWorld1] [2015-06-21 10:46:52 - HellowWorld1] F:\eclipse 32\workspace\HellowWorld1\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 10:46:52 - HellowWorld1] [2015-06-21 10:46:54 - HellowWorld1] F:\eclipse 32\workspace\HellowWorld1\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:46:54 - HellowWorld1] [2015-06-21 10:46:54 - HellowWorld1] F:\eclipse 32\workspace\HellowWorld1\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:46:54 - HellowWorld1] [2015-06-21 10:46:54 - HellowWorld1] F:\eclipse 32\workspace\HellowWorld1\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 10:46:54 - HellowWorld1] [2015-06-21 10:47:05 - HellowWorld1] F:\eclipse 32\workspace\HellowWorld1\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:47:05 - HellowWorld1] [2015-06-21 10:47:05 - HellowWorld1] F:\eclipse 32\workspace\HellowWorld1\res\values-v11\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'. [2015-06-21 10:47:05 - HellowWorld1] [2015-06-21 10:47:05 - HellowWorld1] F:\eclipse 32\workspace\HellowWorld1\res\values-v14\styles.xml:8: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light.DarkActionBar'. [2015-06-21 10:47:05 - HellowWorld1]

今年，我也32了 ，为了不给大家误导，咨询了猎头、圈内好友，以及年过35岁的几位老程序员……舍了老脸去揭人家伤疤……希望能给大家以帮助，记得帮我点赞哦。 目录： 你以为的人生 一次又一次的伤害 猎头界的真相 如何应对互联网行业的「中年危机」 一、你以为的人生 刚入行时，拿着傲人的工资，想着好好干，以为我们的人生是这样的： 等真到了那一天，你会发现，你的人生很可能是这样的： ...

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跳槽几乎是每个人职业生涯的一部分，很多HR说“三年两跳”已经是一个跳槽频繁与否的阈值了，可为什么市面上有很多程序员不到一年就跳槽呢？他们不担心影响履历吗？ PayScale之前发布的**《员工最短任期公司排行榜》中，两家码农大厂Amazon和Google**，以1年和1.1年的员工任期中位数分列第二、第四名。 PayScale:员工最短任期公司排行榜 意外的是，任期中位数极小的这两家公司，薪资...

数据结构与算法思维导图

昨天早上通过远程的方式 review 了两名新来同事的代码，大部分代码都写得很漂亮，严谨的同时注释也很到位，这令我非常满意。但当我看到他们当中有一个人写的 switch 语句时，还是忍不住破口大骂：“我擦，小王，你丫写的 switch 语句也太老土了吧！” 来看看小王写的代码吧，看完不要骂我装逼啊。 private static String createPlayer(PlayerTypes p...

华为面试整体流程大致分为笔试，性格测试，面试，综合面试，回学校等结果。笔试来说，华为的难度较中等，选择题难度和网易腾讯差不多。最后的代码题，相比下来就简单很多，一共3道题目，前2题很容易就AC，题目已经记不太清楚，不过难度确实不大。最后一题最后提交的代码过了75%的样例，一直没有发现剩下的25%可能存在什么坑。 笔试部分太久远，我就不怎么回忆了。直接将面试。 面试 如果说腾讯的面试是挥金如土...

互联网公司工作，很难避免不和黑客们打交道，我呆过的两家互联网公司，几乎每月每天每分钟都有黑客在公司网站上扫描。有的是寻找 Sql 注入的缺口，有的是寻找线上服务器可能存在的漏洞，大部分都...

loonggg读完需要3分钟速读仅需 1 分钟大家好，我是你们的校长。我之前讲过，这年头，只要肯动脑，肯行动，程序员凭借自己的技术，赚钱的方式还是有很多种的。仅仅靠在公司出卖自己的劳动时...

刚才邻居打了个电话说：喂小灰，你家wifi的密码是多少，我怎么连不上了。 我。。。 我也忘了哎，就找到了一个好办法，分享给大家： 第一种情况：已经连接上的wifi，怎么知道密码？ 打开：控制面板\网络和 Internet\网络连接 然后右击wifi连接的无线网卡，选择状态 然后像下图一样： 第二种情况：前提是我不知道啊，但是我以前知道密码。 此时可以利用dos命令了 1、利用netsh wlan...

最近有个老铁，告诉我说，上班一个月，后悔当初着急入职现在公司了。他之前在美图做手机研发，今年美图那边今年也有一波组织优化调整，他是其中一个，在协商离职后，当时捉急找工作上班，因为有房贷供着，不能没有收入来源。所以匆忙选了一家公司，实际上是一个大型外包公司，主要派遣给其他手机厂商做外包项目。**当时承诺待遇还不错，所以就立马入职去上班了。但是后面入职后，发现薪酬待遇这块并不是HR所说那样，那个HR自...

昨天看到一档综艺节目，讨论了两个话题：（1）中国学生的数学成绩，平均下来看，会比国外好？为什么？（2）男生的数学成绩，平均下来看，会比女生好？为什么？同时，我又联想到了一个技术圈经常讨...

原博客再更新，可能就没了，之后将持续更新本篇博客。

提到“程序员”，多数人脑海里首先想到的大约是：为人木讷、薪水超高、工作枯燥…… 然而，当离开工作岗位，撕去层层标签，脱下“程序员”这身外套，有的人生动又有趣，马上展现出了完全不同的A/B面人生！ 不论是简单的爱好，还是正经的副业，他们都干得同样出色。偶尔，还能和程序员的特质结合，产生奇妙的“化学反应”。 @Charlotte：平日素颜示人，周末美妆博主 大家都以为程序媛也个个不修边幅，但我们也许...

文章目录数据库基础知识为什么要使用数据库什么是SQL？什么是MySQL?数据库三大范式是什么mysql有关权限的表都有哪几个MySQL的binlog有有几种录入格式？分别有什么区别？数据类型mysql有哪些数据类型引擎MySQL存储引擎MyISAM与InnoDB区别MyISAM索引与InnoDB索引的区别？InnoDB引擎的4大特性存储引擎选择索引什么是索引？索引有哪些优缺点？索引使用场景（重点）...

有个好朋友ZS，是技术总监，昨天问我：“有一个老下属，跟了我很多年，做事勤勤恳恳，主动性也很好。但随着公司的发展，他的进步速度，跟不上团队的步伐了，有点...

私下里，有不少读者问我：“二哥，如何才能写出一份专业的技术简历呢？我总感觉自己写的简历太烂了，所以投了无数份，都石沉大海了。”说实话，我自己好多年没有写过简历了，但我认识的一个同行，他在阿里，给我说了一些他当年写简历的方法论，我感觉太牛逼了，实在是忍不住，就分享了出来，希望能够帮助到你。 01、简历的本质 作为简历的撰写者，你必须要搞清楚一点，简历的本质是什么，它就是为了来销售你的价值主张的。往深...

当你换槽填坑时，面对一个新的环境。能够快速熟练，上手实现业务需求是关键。但是，哪些因素会影响你快速上手呢？是原有代码写的不够好？还是注释写的不够好？昨夜...

如果世界上都是这种不思进取的软件公司，那别说大部分程序员只会写 3 年代码，恐怕就没有程序员这种职业。

有小伙伴问松哥这个问题，他在上海某公司，在离职了几个月后，前公司的领导联系到他，希望他能够返聘回去，他很纠结要不要回去？ 俗话说好马不吃回头草，但是这个小伙伴既然感到纠结了，我觉得至少说明了两个问题：1.曾经的公司还不错；2.现在的日子也不是很如意。否则应该就不会纠结了。 老实说，松哥之前也有过类似的经历，今天就来和小伙伴们聊聊回头草到底吃不吃。 首先一个基本观点，就是离职了也没必要和老东家弄的苦...

面试官问HTTP与HTTPS的区别，我这样回答让他竖起大拇指！

往往，我们看不进去大段大段的逻辑。深刻的哲理，往往短而精悍，一阵见血。问：产品经理挺漂亮的，有点心动，但不知道合不合得来。男生更看重女生的身材脸蛋，还是...

本文作者用对比非常鲜明的两个开发团队的故事，讲解了敏捷开发之道 —— 如果你的团队缺乏统一标准的环境，那么即使勤劳努力，不仅会极其耗时而且成果甚微，使用...

二哥，有个事想询问下您的意见，您觉得应届生值得去外包吗？公司虽然挺大的，中xx，但待遇感觉挺低，马上要报到，挺纠结的。

当HR压你价，说你只值7K时，你可以流畅地回答，记住，是流畅，不能犹豫。 礼貌地说：“7K是吗？了解了。嗯~其实我对贵司的面试官印象很好。只不过，现在我的手头上已经有一份11K的offer。来面试，主要也是自己对贵司挺有兴趣的，所以过来看看……”（未完） 这段话主要是陪HR互诈的同时，从公司兴趣，公司职员印象上，都给予对方正面的肯定，既能提升HR的好感度，又能让谈判气氛融洽，为后面的发挥留足空间。...

HashMap底层实现原理，红黑树，B+树，B树的结构原理 Spring的AOP和IOC是什么？它们常见的使用场景有哪些？Spring事务，事务的属性，传播行为，数据库隔离级别 Spring和SpringMVC，MyBatis以及SpringBoot的注解分别有哪些？SpringMVC的工作原理，SpringBoot框架的优点，MyBatis框架的优点 SpringCould组件有哪些，他们...

面试阿里p7被问到的问题(当时我只知道第一个)：@Conditional是做什么的?@Conditional多个条件是什么逻辑关系？条件判断在什么时候执...

终于懂了TCP和UDP协议区别

爬取彼岸桌面网站较为简单，用到了requests、lxml、Beautiful Soup4