关于Hive启动后,运行show databases产生java.lang.IllegalAccessError问题

Exception in thread "main" java.lang.IllegalAccessError: tried to access method com.google.common.collect.Iterators.emptyIterator()Lcom/google/common/collect/UnmodifiableIterator; from class org.apache.hadoop.hive.ql.exec.FetchOperator
at org.apache.hadoop.hive.ql.exec.FetchOperator.(FetchOperator.java:108)
at org.apache.hadoop.hive.ql.exec.FetchTask.initialize(FetchTask.java:87)
at org.apache.hadoop.hive.ql.Driver.compile(Driver.java:541)
at org.apache.hadoop.hive.ql.Driver.compileInternal(Driver.java:1317)
at org.apache.hadoop.hive.ql.Driver.runInternal(Driver.java:1457)
at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1237)
at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1227)
at org.apache.hadoop.hive.cli.CliDriver.processLocalCmd(CliDriver.java:233)
at org.apache.hadoop.hive.cli.CliDriver.processCmd(CliDriver.java:184)
at org.apache.hadoop.hive.cli.CliDriver.processLine(CliDriver.java:403)
at org.apache.hadoop.hive.cli.CliDriver.executeDriver(CliDriver.java:821)
at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:759)
at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:686)
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.apache.hadoop.util.RunJar.run(RunJar.java:323)
at org.apache.hadoop.util.RunJar.main(RunJar.java:236)

hive中create table t1(id int);语句可正常运行,但是运行很慢,一条语句花费时间16s。求大佬解答啊!!!!!!!

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运行hive出现的错误Exception in thread "main" java.lang.ClassNotFoundException: org.apache.hive.beeline.HiveSchemaTool

``` [root@bigdata113 bin]# ./schematool -dbType mysql -initSchema Exception in thread "main" java.lang.ClassNotFoundException: org.apache.hive.beeline.HiveSchemaTool at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:348) at org.apache.hadoop.util.RunJar.run(RunJar.java:214) at org.apache.hadoop.util.RunJar.main(RunJar.java:136) ``` 求怎么jie'ju

hive 启动时出现 java.lang.ExceptionInInitializerError

![图片说明](https://img-ask.csdn.net/upload/201912/14/1576309102_505245.jpg) 求问各位大佬,这个到底是哪里出错了?百度了好久都没有找到类似的的错,有一个说是mysql的驱动包没有拷贝进去,但是自己已经拷贝进去了。 hive的版本是1.2.2 mysql驱动包的版本是5.1.47.

启动hive时报错Exception in thread "main" java.lang.NoSuchMethodError: com.google.common.base.Preconditions.checkArgument(ZLjava/lang/String;Ljava/lang/Object;)V

``` Exception in thread "main" java.lang.NoSuchMethodError: com.google.common.base.Preconditions.checkArgument(ZLjava/lang/String;Ljava/lang/Object;)V at org.apache.hadoop.conf.Configuration.set(Configuration.java:1357) at org.apache.hadoop.conf.Configuration.set(Configuration.java:1338) at org.apache.hadoop.mapred.JobConf.setJar(JobConf.java:536) at org.apache.hadoop.mapred.JobConf.setJarByClass(JobConf.java:554) at org.apache.hadoop.mapred.JobConf.<init>(JobConf.java:448) at org.apache.hadoop.hive.conf.HiveConf.initialize(HiveConf.java:5141) at org.apache.hadoop.hive.conf.HiveConf.<init>(HiveConf.java:5099) at org.apache.hadoop.hive.common.LogUtils.initHiveLog4jCommon(LogUtils.java:97) at org.apache.hadoop.hive.common.LogUtils.initHiveLog4j(LogUtils.java:81) at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:699) at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:683) 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.apache.hadoop.util.RunJar.run(RunJar.java:323) at org.apache.hadoop.util.RunJar.main(RunJar.java:236) ```

Hive请正常,在show databases;报错,求大神解答

2018-02-01T09:46:28,400 WARN [9a4cc1b4-8396-471b-8df0-b1eb3ca1fd82 main] ql.Driver: Caught exception attempting to write metadata call information org.apache.hadoop.hive.ql.metadata.HiveException: java.lang.RuntimeException: Unable to instantiate org.apache.hadoop.hive.ql.metadata.SessionHiveMetaStoreClient org.apache.hadoop.hive.ql.metadata.HiveException: java.lang.RuntimeException: Unable to instantiate org.apache.hadoop.hive.ql.metadata.SessionHiveMetaStoreClient at org.apache.hadoop.hive.ql.metadata.Hive.registerAllFunctionsOnce(Hive.java:236) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.<init>(Hive.java:388) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.create(Hive.java:332) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.getInternal(Hive.java:312) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.get(Hive.java:354) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.get(Hive.java:350) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.Driver.dumpMetaCallTimingWithoutEx(Driver.java:683) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.Driver.compile(Driver.java:621) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.Driver.compileInternal(Driver.java:1317) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.Driver.runInternal(Driver.java:1457) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1237) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1227) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.cli.CliDriver.processLocalCmd(CliDriver.java:233) ~[hive-cli-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.cli.CliDriver.processCmd(CliDriver.java:184) ~[hive-cli-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.cli.CliDriver.processLine(CliDriver.java:403) ~[hive-cli-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.cli.CliDriver.executeDriver(CliDriver.java:821) ~[hive-cli-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:759) ~[hive-cli-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:686) ~[hive-cli-2.3.2.jar:2.3.2] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_151] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_151] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_151] at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_151] at org.apache.hadoop.util.RunJar.run(RunJar.java:239) ~[hadoop-common-2.9.0.jar:?] at org.apache.hadoop.util.RunJar.main(RunJar.java:153) ~[hadoop-common-2.9.0.jar:?] Caused by: java.lang.RuntimeException: Unable to instantiate org.apache.hadoop.hive.ql.metadata.SessionHiveMetaStoreClient at org.apache.hadoop.hive.metastore.MetaStoreUtils.newInstance(MetaStoreUtils.java:1701) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.<init>(RetryingMetaStoreClient.java:83) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.getProxy(RetryingMetaStoreClient.java:133) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.getProxy(RetryingMetaStoreClient.java:104) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.createMetaStoreClient(Hive.java:3600) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.getMSC(Hive.java:3652) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.getMSC(Hive.java:3632) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.getAllFunctions(Hive.java:3894) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.reloadFunctions(Hive.java:248) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.registerAllFunctionsOnce(Hive.java:231) ~[hive-exec-2.3.2.jar:2.3.2] ... 23 more Caused by: java.lang.reflect.InvocationTargetException at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_151] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[?:1.8.0_151] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:1.8.0_151] at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[?:1.8.0_151] at org.apache.hadoop.hive.metastore.MetaStoreUtils.newInstance(MetaStoreUtils.java:1699) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.<init>(RetryingMetaStoreClient.java:83) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.getProxy(RetryingMetaStoreClient.java:133) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.getProxy(RetryingMetaStoreClient.java:104) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.createMetaStoreClient(Hive.java:3600) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.getMSC(Hive.java:3652) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.getMSC(Hive.java:3632) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.getAllFunctions(Hive.java:3894) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.reloadFunctions(Hive.java:248) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.registerAllFunctionsOnce(Hive.java:231) ~[hive-exec-2.3.2.jar:2.3.2] ... 23 more Caused by: org.apache.hadoop.hive.metastore.api.MetaException: Version information not found in metastore. at org.apache.hadoop.hive.metastore.RetryingHMSHandler.<init>(RetryingHMSHandler.java:83) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.RetryingHMSHandler.getProxy(RetryingHMSHandler.java:92) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.HiveMetaStore.newRetryingHMSHandler(HiveMetaStore.java:6893) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.<init>(HiveMetaStoreClient.java:164) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.SessionHiveMetaStoreClient.<init>(SessionHiveMetaStoreClient.java:70) ~[hive-exec-2.3.2.jar:2.3.2] at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_151] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[?:1.8.0_151] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:1.8.0_151] at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[?:1.8.0_151] at org.apache.hadoop.hive.metastore.MetaStoreUtils.newInstance(MetaStoreUtils.java:1699) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.<init>(RetryingMetaStoreClient.java:83) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.getProxy(RetryingMetaStoreClient.java:133) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.getProxy(RetryingMetaStoreClient.java:104) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.createMetaStoreClient(Hive.java:3600) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.getMSC(Hive.java:3652) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.getMSC(Hive.java:3632) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.getAllFunctions(Hive.java:3894) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.reloadFunctions(Hive.java:248) ~[hive-exec-2.3.2.jar:2.3.2] at org.apache.hadoop.hive.ql.metadata.Hive.registerAllFunctionsOnce(Hive.java:231) ~[hive-exec-2.3.2.jar:2.3.2] ... 23 more 2018-02-01T09:46:28,400 INFO [9a4cc1b4-8396-471b-8df0-b1eb3ca1fd82 main] ql.Driver: Completed compiling command(queryId=root_20180201094627_6a378f28-ae24-4c00-8d15-a8df87e7020e); Time taken: 0.474 seconds

异常java.lang.reflect.InvocationTargetException

``` java.lang.reflect.InvocationTargetException 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 com.web.servlet.BaseServlet.service(BaseServlet.java:34) 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 com.web.filter.EncodingFilter.doFilter(EncodingFilter.java:36) 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:501) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) 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:408) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313) 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.NumberFormatException: null at java.lang.Integer.parseInt(Integer.java:454) at java.lang.Integer.parseInt(Integer.java:527) at com.web.servlet.ProductServlet.findByPage(ProductServlet.java:52) ... 28 more ```

java.lang.ClassNotFoundException问题

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java.lang.ClassNotFoundException异常有哪些可能

新手一枚,写了个Struts2的demo,导入Struts2.3.4的jar包,用MyEclipse10自带的tomcat跑然后报错 严重: Exception starting filter struts2base01 java.lang.ClassNotFoundException: org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExcuteFilter at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1358) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1204) at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:249) at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:397) at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:108) at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:3693) at org.apache.catalina.core.StandardContext.start(StandardContext.java:4340) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:525) at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:920) at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:883) at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492) at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1138) at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311) at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053) at org.apache.catalina.core.StandardHost.start(StandardHost.java:719) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045) at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443) at org.apache.catalina.core.StandardService.start(StandardService.java:516) at org.apache.catalina.core.StandardServer.start(StandardServer.java:710) at org.apache.catalina.startup.Catalina.start(Catalina.java:566) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288) at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413) 2016-5-6 16:08:43 org.apache.catalina.core.StandardContext start 严重: Error filterStart 2016-5-6 16:08:43 org.apache.catalina.core.StandardContext start 严重: Context [/Struts2_base01] startup failed due to previous errors

java.lang.ClassCastException

java.lang.ClassCastException: org.restlet.ext.json.JsonConverter cannot be cast to org.restlet.engine.converter.ConverterHelper

Exception in thread "main" java.lang.NoClassDefFoundError如何解决

本人初学Hibernate框架,网络上找的视频自学的,刚刚到第一次运行文件就出现这个错误,用的是eclipse,错误代码如下: ``` Exception in thread "main" java.lang.NoClassDefFoundError: javax/xml/bind/JAXBException at org.hibernate.boot.spi.XmlMappingBinderAccess.<init>(XmlMappingBinderAccess.java:43) at org.hibernate.boot.MetadataSources.<init>(MetadataSources.java:87) at org.hibernate.cfg.Configuration.<init>(Configuration.java:123) at org.hibernate.cfg.Configuration.<init>(Configuration.java:118) at cn.ljs.text.HibernateTest.main(HibernateTest.java:13) Caused by: java.lang.ClassNotFoundException: javax.xml.bind.JAXBException at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(Unknown Source) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(Unknown Source) at java.base/java.lang.ClassLoader.loadClass(Unknown Source) ... 5 more ``` 文件代码如下: ``` package cn.ljs.text; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.boot.registry.StandardServiceRegistryBuilder; import org.hibernate.cfg.Configuration; import org.hibernate.service.ServiceRegistry; import cn.ljs.pojo.User; public class HibernateTest { public static void main(String[] args) { Configuration cfg=new Configuration().configure(); ServiceRegistry registry=new StandardServiceRegistryBuilder().applySettings(cfg.getProperties()).build(); SessionFactory factory=cfg.buildSessionFactory(registry); Session session=factory.openSession(); User user=(User) session.get(User.class, 1); System.out.println(user); session.close(); factory.close(); } } ``` 很简单,就是测试一下布置有没有问题 以下是包图: ![图片说明](https://img-ask.csdn.net/upload/201902/15/1550193069_565517.jpg) 跟着教学视频走的,代码无误,视频里直接输出了数据库表中的信息,而我就报错... 已自行百度后作出以下修改: ------------------------- 1.将jar包修改到classpath目录下, ![图片说明](https://img-ask.csdn.net/upload/201902/15/1550193227_189559.jpg) 无效 2.修改classpath等配置, ![图片说明](https://img-ask.csdn.net/upload/201902/15/1550193280_600490.jpg) ![图片说明](https://img-ask.csdn.net/upload/201902/15/1550193296_623025.jpg) path:D:\OracleWINDOWS.X64_180000_db_home\bin;%JAVA_HOME%\bin;%MAVEN_HOME%\bin;C:\Program Files (x86)\Common Files\Oracle\Java\javapath;D:\java\bin;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\system32\wbem 我半路出家,在外面培训班学过4个月java基础,学的是SSM框架,现在想自己拓展一下学习Hibernate,哪知道一开始就遇到这问题 o(╥﹏╥)o,请高手指点!谢谢!

运行hadoop 报错Error: java.lang.ArrayIndexOutOfBoundsException: 1,感觉程序没问题

``` public class HH { public static class HHMapper extends Mapper<LongWritable,Text,Text,IntWritable>{ private Text map_key=new Text(); private IntWritable map_value=new IntWritable(); protected void map(LongWritable key,Text value,Context context) throws IOException,InterruptedException{ //System.out.println(value.toString()); String[] H=value.toString().split("\t"); String[] h=H[1].split(","); int[][] R=new int[h.length][h.length]; for(int i=0;i<h.length;i++) for(int j=0;j<h.length;j++){ R[i][j]=Integer.parseInt(h[i])*Integer.parseInt(h[j]); map_key.set(H[0]+","+j); // map_key.set(H[0]); map_value.set((R[i][j])); // map_value.set(1); context.write(map_key, map_value); } } } ``` 感觉程序没问题 就是报下标越界错误,文件格式也没问题啊

Hive执行SQL语句报错hive> show databases; ----已解决

``` hive> show databases; FAILED: SemanticException org.apache.hadoop.hive.ql.metadata.HiveException: java.lang.RuntimeException: Unable to instantiate org.apache.hadoop.hive.ql.metadata.SessionHiveMetaStoreClient hive> ``` 百度了很多,都是下面的解决方法 ``` 修改hive的配置文件hive-site.xml <property> <name>datanucleus.schema.autoCreateAll</name> <value>true</value> </property> 然后删除MySQL中原来的表 drop database hive_metastore; 重新初始化元数据 schematool -dbType mysql -initSchema ``` 按照上面的操作执行后,还是报相同的错误 请问,这个如何解决? 已解决:在多次挣扎后,我尝试了网上很多的方法,但都没有成功;经过多次修改与测试,最终终于找到了问题所在,原来只是java的版本出现的问题,与hive的版本不匹配,我开始使用的是java的最新版jdk-10.0.2,我开始的想法是高版本的能兼容低版本,后来验证我的想法是错的,我将java换成jdk8后,嘿,一下子就可以了,哎,怪我没有好好的认真看一下官方的文档,浪费了我两天的时间啊。

找不到 包:java.lang.ClassNotFoundException: org.apache.commons.lang.StringUtils

如题找不到commons.lang这个包,我已经导入了还是不能用,不管是用哪个版本包都找不到,但是我能从代码里面找到StringUtils这个方法源代码; ![图片说明](https://img-ask.csdn.net/upload/201904/14/1555245166_764372.png)

IDEA运行jboss出错,java.lang.IllegalArgumentException port out of range:2147483647

使用IDEA运行JBOSS项目时,报错![图片说明](https://img-ask.csdn.net/upload/201903/09/1552119526_563262.png) 在网上查找大多数说是端口问题,可是使用命令也没看到端口被占用,求问各位大佬解决方案。

启动Hive报错unknownHostException

**之前改过一次主机名,修改了etc/hosts和 etc/sysconfig/network里的hostname, hadoop的core-site.xml中也做出相应修改, 但用hive命令启动后,报错:** ``` Exception in thread "main" java.lang.IllegalArgumentException: java.net.UnknownHostException: hadoop000 at org.apache.hadoop.security.SecurityUtil.buildTokenService(SecurityUtil.java:374) at org.apache.hadoop.hdfs.NameNodeProxies.createNonHAProxy(NameNodeProxies.java:310) at org.apache.hadoop.hdfs.NameNodeProxies.createProxy(NameNodeProxies.java:176) at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:708) at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:651) at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.java:149) at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2696) at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:94) at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2733) at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2715) at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:382) at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:181) at org.apache.hadoop.hive.ql.session.SessionState.start(SessionState.java:583) at org.apache.hadoop.hive.ql.session.SessionState.beginStart(SessionState.java:553) at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:750) at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:686) 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.apache.hadoop.util.RunJar.run(RunJar.java:221) at org.apache.hadoop.util.RunJar.main(RunJar.java:136) Caused by: java.net.UnknownHostException: hadoop000 ... 22 more ``` hadoop000是我之前的主机名,搞不明白hive是在哪个配置文件里读到的,所以无从下手修改,求助各位大佬,感激不尽!!

hadoop 报java.lang.InstantiationException

package mapreduce; import java.io.IOException; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Job; import org.apache.hadoop.mapreduce.Mapper; import org.apache.hadoop.mapreduce.Reducer; import org.apache.hadoop.mapreduce.lib.input.FileInputFormat; import org.apache.hadoop.mapreduce.lib.input.TextInputFormat; import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; import org.apache.hadoop.mapreduce.lib.partition.HashPartitioner; public class WordCountApp { static final String INPUT_PATH = "hdfs://chaoren:9000/hello"; static final String OUTPUT_PATH = "hdfs://chaoren:9000/hello_statics"; public static void main(String[] args) throws Exception { Configuration conf = new Configuration(); Job job = new Job(conf, WordCountApp.class.getSimpleName()); //1。1输入的目录在哪里 FileInputFormat.setInputPaths(job, INPUT_PATH); //指定对输入的数据进行格式化处理 job.setInputFormatClass(TextInputFormat.class); //1.2指定自定义的mapper类 job.setMapperClass(MyMapper.class); //指定map输出的<key,value>类型 job.setMapOutputKeyClass(Text.class); job.setMapOutputValueClass(LongWritable.class); //1.3 分区 job.setPartitionerClass(HashPartitioner.class); job.setNumReduceTasks(1); //1.4 TODO 排序分组 //1.5 TODO <可选>规约 //2.2指定自定义的Reducer类 job.setReducerClass(MyReducer.class); job.setOutputKeyClass(Text.class); job.setOutputValueClass(LongWritable.class); //2.2指定输出路径 FileOutputFormat.setOutputPath(job, new Path(OUTPUT_PATH)); //2.3指定输出的格式化类 job.setOutputFormatClass(FileOutputFormat.class); //把作业提交jobTracker运行 job.waitForCompletion(true); } /** * KEYIN 即k1 表示每一行的起始位置<偏移量> * VALUEIN 即v1 表示每一行的文本内容 * KEYOUT 即k1 表示每一行中的单词 * VALUEOUT 即v1 表示每一行中,每个单词出现的次数 * @author Administrator * */ static class MyMapper extends Mapper<LongWritable, Text, Text, LongWritable> { @Override protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException { String[] splited = value.toString().split("\t"); for(String word : splited) { context.write(new Text(word), new LongWritable(1)); } } } /** * KEYIN 即k2 表示每一行中每个单词 * VALUEIN 即v2 表示每一行中每个单词出现的次数 * KEYOUT 即k3 表示整个文件中的不同单词 * VALUEOUT 即v3 表示整个文件中的不同单词的出现总数 * @author Administrator * */ static class MyReducer extends Reducer<Text,LongWritable, Text, LongWritable>{ protected void reduce(Text k2, Iterable<LongWritable> v2s, Context context) throws IOException, InterruptedException { long sum = 0l; for(LongWritable v2 : v2s){ sum+=v2.get(); } context.write(k2, new LongWritable(sum)); } } }

hadoop hive 初始化报错

环境:centos7 hadoop3.1.2 hive2.3.0 [root@hadoop metastore]# schematool -initSchema -dbType mysql Exception in thread "main" java.lang.ClassNotFoundException: org.apache.hive.beeline.HiveSchemaTool at java.net.URLClassLoader.findClass(URLClassLoader.java:382) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:348) at org.apache.hadoop.util.RunJar.run(RunJar.java:311) at org.apache.hadoop.util.RunJar.main(RunJar.java:232) [root@hadoop metastore]# hive which: no hbase in (/root/mysql/apache-hive-2.3.0-bin/bin:/root/train/hadoop-3.1.2/sbin:/root/train/hadoop-3.1.2/bin:/root/train/jdk1.8.0_211/bin:/root/train/hive/bin:/root/train/hadoop-3.1.2/sbin:/root/train/hadoop-3.1.2/bin:/root/train/jdk1.8.0_211/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin) Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/hive/ql/CommandNeedRetryException at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:348) at org.apache.hadoop.util.RunJar.run(RunJar.java:311) at org.apache.hadoop.util.RunJar.main(RunJar.java:232) Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.hive.ql.CommandNeedRetryException at java.net.URLClassLoader.findClass(URLClassLoader.java:382) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ... 4 more Navicat Premium 都能成功登入mysql建立的hive数据库 hive 配置文件都没问题 mysql连接器也放入了lib

java.lang.NullPointerException?请大家帮忙看看是哪里有问题

package jishuhuanfang; import java.io.IOException; public class constant { int arr[][]; int i,j; int k=1; void jishu(int n) { for(i=0;i<n;i++) for(j=0;j<n;j++) arr[i][j]=0; j=(n+1)/2-1; i=0; while(k<=n*n) { if(arr[i][j]!=0) i=i+1; arr[i][j]=k; k=k+1; if(j+1==n&&i-1==-1) i=i+1; else if(i-1==-1) { i=n-1; j=j+1; } else if(j+1==n) { j=0; i=i-1; } else { j=j+1; i=i-1; } } for(i=0;i<n;i++) { for(j=0;j<n;j++) { System.out.print(arr[i][j]+" "); } System.out.print("\n"); } } public static void main(String[] args) throws IOException { constant test=new constant(); System.out.println("输入n:"); int n=System.in.read(); test.jishu(n); /* if(n%2==1) //奇数阶幻方 else if(n==2) System.out.println("不存在2阶幻方"); else if(n%4==0) //4k偶数阶幻方 else //4k+2偶数阶幻方 */ } } ``` ``` 输入n: 5 Exception in thread "main" java.lang.NullPointerException at jishuhuanfang.constant.jishu(constant.java:13) at jishuhuanfang.constant.main(constant.java:56) 我该怎么修改呢?

hive库中的表查询时报错,其他的表可以正常查询,只有这个表不行

Diagnostic Messages for this Task: Error: java.io.IOException: java.lang.reflect.InvocationTargetException at org.apache.hadoop.hive.io.HiveIOExceptionHandlerChain.handleRecordReaderCreationException(HiveIOExceptionHandlerChain.java:97) at org.apache.hadoop.hive.io.HiveIOExceptionHandlerUtil.handleRecordReaderCreationException(HiveIOExceptionHandlerUtil.java:57) at org.apache.hadoop.hive.shims.HadoopShimsSecure$CombineFileRecordReader.initNextRecordReader(HadoopShimsSecure.java:266) at org.apache.hadoop.hive.shims.HadoopShimsSecure$CombineFileRecordReader.<init>(HadoopShimsSecure.java:213) at org.apache.hadoop.hive.shims.HadoopShimsSecure$CombineFileInputFormatShim.getRecordReader(HadoopShimsSecure.java:333) at org.apache.hadoop.hive.ql.io.CombineHiveInputFormat.getRecordReader(CombineHiveInputFormat.java:720) at org.apache.hadoop.mapred.MapTask$TrackedRecordReader.<init>(MapTask.java:169) at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:432) at org.apache.hadoop.mapred.MapTask.run(MapTask.java:343) at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:422) at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1785) at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158) Caused by: java.lang.reflect.InvocationTargetException at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:423) at org.apache.hadoop.hive.shims.HadoopShimsSecure$CombineFileRecordReader.initNextRecordReader(HadoopShimsSecure.java:252) ... 11 more Caused by: java.lang.IndexOutOfBoundsException: toIndex = 608 at java.util.ArrayList.subListRangeCheck(ArrayList.java:1004) at java.util.ArrayList.subList(ArrayList.java:996) at org.apache.hadoop.hive.ql.io.orc.RecordReaderFactory.getSchemaOnRead(RecordReaderFactory.java:161) at org.apache.hadoop.hive.ql.io.orc.RecordReaderFactory.createTreeReader(RecordReaderFactory.java:66) at org.apache.hadoop.hive.ql.io.orc.RecordReaderImpl.<init>(RecordReaderImpl.java:202) at org.apache.hadoop.hive.ql.io.orc.ReaderImpl.rowsOptions(ReaderImpl.java:541) at org.apache.hadoop.hive.ql.io.orc.OrcInputFormat.createReaderFromFile(OrcInputFormat.java:232) at org.apache.hadoop.hive.ql.io.orc.OrcInputFormat$OrcRecordReader.<init>(OrcInputFormat.java:165) at org.apache.hadoop.hive.ql.io.orc.OrcInputFormat.getRecordReader(OrcInputFormat.java:1156) at org.apache.hadoop.hive.ql.io.CombineHiveRecordReader.<init>(CombineHiveRecordReader.java:67) ... 16 more

Java.lang.IllegalAccessError异常

写的代码在本地运行没有问题,拿在服务器上报了这么个错误 ![图片说明](https://img-ask.csdn.net/upload/201512/18/1450410179_61933.jpg) 大家帮忙看下,是哪里出了问题,本地JDK1.6,服务器上是jdk1.7,ORACLE驱动是ojdbc14

Python可以这样学(第一季:Python内功修炼)

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手把手实现Java图书管理系统(附源码)

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cuda开发cutilDLL

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