!SESSION Thu Apr 08 15:32:25 CST 2021 ------------------------------------------ !ENTRY org.eclipse.equinox.launcher 4 0 2021-04-08 15:32:26.003 !MESSAGE Could not find extension: reference:file:org.eclipse.osgi.compatibility.state_1.1.500.v20190516-1407.jar !ENTRY org.eclipse.equinox.launcher 4 0 2021-04-08 15:32:26.012 !MESSAGE Exception launching the Eclipse Platform: !STACK java.lang.ClassNotFoundException: org.eclipse.core.runtime.adaptor.EclipseStarter     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 org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:657)     at org.eclipse.equinox.launcher.Main.basicRun(Main.java:597)     at org.eclipse.equinox.launcher.Main.run(Main.java:1468)

有个根据文档页数判断当前学习进度百分之多少的课程。 已试过 poi 和 apose.words读取，均页数不对称； 试过spire.doc包，发现预读取调用jar要6s 第一次读取文档时长太长。 求求求求求！！！！！！！！！

类

请教大神帮忙看看，应该是不同jar包有相同的方法导致错误，但是不知道怎么找。 Workbook workbook = new Workbook(); 用的import com.spire.xls.*;jar包 代码不报错，但是执行到这代码会后台报错 警告: #{var_SyglControlBean.btn_6_onclick_action}: java.lang.NoSuchMethodError: com.spire.pdf.grid.PdfGridRow.spr  (Ljava/lang/String;)Ljava/lang/String; javax.faces.FacesException: #{var_SyglControlBean.btn_6_onclick_action}: java.lang.NoSuchMethodError: com.spire.pdf.grid.PdfGridRow.spr  (Ljava/lang/String;)Ljava/lang/String;     at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:118)     at javax.faces.component.UICommand.broadcast(UICommand.java:315)     at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:790)     at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1282)     at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)     at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)     at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:198)     at javax.faces.webapp.FacesServlet.service(FacesServlet.java:654)     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)     at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)     at com.zdk.platform.jsfsupport.filter.SessionValid.doFilter(SessionValid.java:308)     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)     at org.springframework.orm.hibernate4.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:150)     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)     at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)     at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)     at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)     at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)     at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1526)     at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1482)     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)     at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)     at java.lang.Thread.run(Thread.java:745) Caused by: javax.faces.el.EvaluationException: java.lang.NoSuchMethodError: com.spire.pdf.grid.PdfGridRow.spr  (Ljava/lang/String;)Ljava/lang/String;     at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:101)     at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)  

相同maven配置、网络、Eclipse等。 新检出项目，下载jar包。 其他人可以下载，自己一直下载失败，删除jar包后再下载也下载失败？？

java.lang.NoClassDefFoundError: Could not initialize class org.apache.poi.hssf.util.HSSFColor$HSSFColorPredefined     org.apache.poi.hssf.model.InternalWorkbook.createExtendedFormat(InternalWorkbook.java:1382)     org.apache.poi.hssf.model.InternalWorkbook.createCellXF(InternalWorkbook.java:868)     org.apache.poi.hssf.usermodel.HSSFWorkbook.createCellStyle(HSSFWorkbook.java:1251)     com.manage.utils.ExportExcelUtil.createSXSSFWorkbook(ExportExcelUtil.java:35)     com.manage.web.ExportingStudentList.doGet(ExportingStudentList.java:60)     javax.servlet.http.HttpServlet.service(HttpServlet.java:626)     javax.servlet.http.HttpServlet.service(HttpServlet.java:733)     org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

Caused by: org.springframework.boot.autoconfigure.jdbc.DataSourceProperties$DataSourceBeanCreationException: Cannot determine embedded database driver class for database type NONE. If you want an embedded database please put a supported one on the classpath. If you have database settings to be loaded from a particular profile you may need to active it (no profiles are currently active). springboot项目在idea上运行没问题，打成jar包运行报上面的错误，求路过的大佬指教 配置文件如下：  

如上图，今天用boot项目发送post请求，一直发不出去，追查到这里，代码位置：jdk1.8\src\sun\net\www\protocol\http\HttpURLConnection.java 1068行，查了资料说是因为安全管理器没有启用，返回的是null，导致请求无法发出，请问下各位大佬，怎么样能使这个不返回null? 

No JUnit tests found. java.lang.Exception: Test class should have exactly one public zero-argument constructor  

如图：mvn依赖： <dependencies> <!-- https://mvnrepository.com/artifact/junit/junit --> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.9</version> </dependency> </dependencies>   junit无论换什么版本都是这样，repository删掉重新下载也是这样，无语了。。。。，求大佬解答

目前还在使用16.0v版，有很多指令反馈不出来了，如invxr显示不全，sdi居然无此指令，希望能更新到19以上，谢谢

在看类加载器的层次图的时候，发现在同一个层次上不同的图是不一样的，有的是system class loader，而有的是appclassloader，所以想问一下system class loader和appclassloader是同一个加载器吗？是不是只是名称不同。

人已经崩溃了 pom文件中导入了servlet-api用tomcat7:run可以跑起来但是在使用junit测试时却报错找不到servlet

一段简单的遍历中, List.forEach中的临时变量不能用来赋值,因为它是个临时的复制, 求大佬解答下代码出错在那里 首先是一个简单的类: public class ImportDataBean { private String name; private Object value; public ImportDataBean(String name) { this.name = name; } @Override public String toString(){ return "\n name: "+name +" value: " +value; } public ImportDataBean() { } } 最后是遍历代码: public static void main(String[] args) { List<ImportDataBean> importHeadList=new ArrayList(); List<ImportDataBean> importBodyList=new ArrayList(); ImportDataBean importDataBean1=new ImportDataBean("名称"); ImportDataBean importDataBean2=new ImportDataBean("备注"); ImportDataBean importDataBean3=new ImportDataBean("创建时间"); importHeadList.add(importDataBean1); importHeadList.add(importDataBean2); importHeadList.add(importDataBean3); for (int i=0;i<importHeadList.size();i++){ for(ImportDataBean importDataBean:importHeadList){ importDataBean.setValue(i); importDataBean.setName(importDataBean.getName()); //System.out.println(importDataBean.toString()); importBodyList.add(importDataBean); //ImportDataBean importDataSetBean=new ImportDataBean(); //importDataSetBean.setValue(i); //importDataSetBean.setName(importDataBean.getName()); //importBodyList.add(importDataSetBean); } } for (ImportDataBean importDataBean:importBodyList){ System.out.println(importDataBean.toString()); } } 觉得我这段代码有什么问题吗？没错，直接用 ForEach的临时变量操作是不是有点不妥,  贴一下执行结果: 可以看到 name的赋值还正常， value的赋值都变成2 这让我有点懵圈，如果正常的 重新 New一个  ImportDataBean 对象用于赋值，输出结果是没有问题的 如果把注释的输出放开 importDataBean.setValue(i); importDataBean.setName(importDataBean.getName()); System.out.println(importDataBean.toString()); importBodyList.add(importDataBean); 输出结果: 红色标红就是遍历中的 print了，这是为什么呢,Name没有错，但是value

解释内存中的栈(stack)、堆(heap)和方法区(method area)的用法。

请问各位大神,对于Connection这个类,在java.sql包下有这个类,同时我竟然发现在我导入的mysql的包下也有这个类,从源码的层面上可以看出,mysql的connection是继承与sql类下的,那么这两者有什么区别吗?我们能否通过mysql的connection来构建预编译对象呢?(preparedStatement)  

!SESSION 2021-04-18 01:45:12.592 ----------------------------------------------- eclipse.buildId=M20130204-1200 java.version=15 java.vendor=Oracle Corporation BootLoader constants: OS=win32, ARCH=x86_64, WS=win32, NL=zh_CN Framework arguments:  -product com.android.ide.eclipse.adt.package.adtproduct Command-line arguments:  -os win32 -ws win32 -arch x86_64 -product com.android.ide.eclipse.adt.package.adtproduct !ENTRY org.eclipse.equinox.simpleconfigurator 4 0 2021-04-18 01:45:13.131 !MESSAGE FrameworkEvent ERROR !STACK 0 org.osgi.framework.BundleException: The bundle "org.eclipse.equinox.simpleconfigurator_1.0.301.v20120914-163612 [1]" could not be resolved. Reason: Missing Constraint: Bundle-RequiredExecutionEnvironment: CDC-1.1/Foundation-1.1,J2SE-1.4     at org.eclipse.osgi.framework.internal.core.AbstractBundle.getResolverError(AbstractBundle.java:1332)     at org.eclipse.osgi.framework.internal.core.AbstractBundle.getResolutionFailureException(AbstractBundle.java:1316)     at org.eclipse.osgi.framework.internal.core.BundleHost.startWorker(BundleHost.java:323)     at org.eclipse.osgi.framework.internal.core.AbstractBundle.resume(AbstractBundle.java:390)     at org.eclipse.osgi.framework.internal.core.Framework.resumeBundle(Framework.java:1176)     at org.eclipse.osgi.framework.internal.core.StartLevelManager.resumeBundles(StartLevelManager.java:559)     at org.eclipse.osgi.framework.internal.core.StartLevelManager.resumeBundles(StartLevelManager.java:544)     at org.eclipse.osgi.framework.internal.core.StartLevelManager.incFWSL(StartLevelManager.java:457)     at org.eclipse.osgi.framework.internal.core.StartLevelManager.doSetStartLevel(StartLevelManager.java:243)     at org.eclipse.osgi.framework.internal.core.StartLevelManager.dispatchEvent(StartLevelManager.java:438)     at org.eclipse.osgi.framework.internal.core.StartLevelManager.dispatchEvent(StartLevelManager.java:1)     at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:230)     at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.run(EventManager.java:340) !ENTRY org.eclipse.osgi 4 0 2021-04-18 01:45:13.137 !MESSAGE Bundle initial@reference:file:plugins/org.eclipse.equinox.simpleconfigurator_1.0.301.v20120914-163612.jar was not resolved. !ENTRY org.eclipse.osgi 2 0 2021-04-18 01:45:13.143 !MESSAGE One or more bundles are not resolved because the following root constraints are not resolved: !SUBENTRY 1 org.eclipse.osgi 2 0 2021-04-18 01:45:13.143 !MESSAGE Bundle initial@reference:file:plugins/org.eclipse.equinox.simpleconfigurator_1.0.301.v20120914-163612.jar was not resolved. !SUBENTRY 2 org.eclipse.equinox.simpleconfigurator 2 0 2021-04-18 01:45:13.144 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(|(&(osgi.ee=CDC/Foundation)(version=1.1))(&(osgi.ee=JavaSE)(version=1.4)))". !ENTRY org.eclipse.osgi 2 0 2021-04-18 01:45:13.145 !MESSAGE The following is a complete list of bundles which are not resolved, see the prior log entry for the root cause if it exists: !SUBENTRY 1 org.eclipse.osgi 2 0 2021-04-18 01:45:13.145 !MESSAGE Bundle org.eclipse.equinox.simpleconfigurator_1.0.301.v20120914-163612 [1] was not resolved. !SUBENTRY 2 org.eclipse.equinox.simpleconfigurator 2 0 2021-04-18 01:45:13.145 !MESSAGE Missing required capability Require-Capability: osgi.ee; filter="(|(&(osgi.ee=CDC/Foundation)(version=1.1))(&(osgi.ee=JavaSE)(version=1.4)))". !ENTRY org.eclipse.osgi 4 0 2021-04-18 01:45:13.155 !MESSAGE Application error !STACK 1 java.lang.IllegalStateException: Unable to acquire application service. Ensure that the org.eclipse.core.runtime bundle is resolved and started (see config.ini).     at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:74)     at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353)     at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180)     at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)     at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)     at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)     at java.base/java.lang.reflect.Method.invoke(Method.java:564)     at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629)     at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)     at org.eclipse.equinox.launcher.Main.run(Main.java:1438)     at org.eclipse.equinox.launcher.Main.main(Main.java:1414)

但是我的本地可以用SSH工具连接到数据库，我的账号密码都没有问题，之前把项目放到过windows服务器上可以正常运行，但是Linux上就不行，现在的情况是war项目不能访问，但是静态的HTML可以访问 Tomcat输出日志： 18-Apr-2021 09:07:39.711 WARNING [C3P0PooledConnectionPoolManager-Helper Thread-#1] com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@7242abf8 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception:      java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: YES)         at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:963)         at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3966)         at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3902)         at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:875)         at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1712)         at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1228)         at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2253)         at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2284)         at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2083)         at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:806)         at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)         at jdk.internal.reflect.GeneratedConstructorAccessor18.newInstance(Unknown Source)         at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)         at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)         at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)         at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)         at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:410)         at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:328)         at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)         at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:183)         at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:172)         at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:152)         at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1074)         at com.mchange.v2.resourcepool.BasicResourcePool.doAcquireAndDecrementPendingAcquiresWithinLockOnSuccess(BasicResourcePool.java:1061)         at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)         at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1796)         at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:635) 18-Apr-2021 09:07:39.715 WARNING [C3P0PooledConnectionPoolManager-Helper Thread-#1] com.mchange.v2.resourcepool.BasicResourcePool.forceKillAcquires Having failed to acquire a resource, com.mchange.v2.resourcepool.BasicResourcePool@60019565 is interrupting all Threads waiting on a resource to check out. Will try again in response to new client requests. Sun Apr 18 09:07:40 CST 2021 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification. Sun Apr 18 09:07:40 CST 2021 WARN: Establishing SSL connec

下面那个错误一直不懂怎么调试，有没有大佬能教一下

  1.这是分区的代码 2.这是map的代码 3.这是reduce的代码  4.这是主函数   运行JobMain时报错 请问大佬们这怎么解决呀，尝试了各种方法都不行，快炸了

如何实现对象克隆？如何实现对象克隆？

编写程序，将2~10000之间的素数保存到数组，输出这些素数的平均值，输出小于8000的最大素数、输出大于1000的最小素数。谢谢大神

 java.lang.UnsatisfiedLinkError: /usr/lib/libCollapse.so: /lib64/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /usr/lib/libCollapse.so)这是为什么，找不到吗  

java.lang.UnsatisfiedLinkError: /usr/lib/libCollapse.so: /usr/lib64/libm.so.6: version `GLIBC_2.29' not found (required by /usr/lib/libCollapse.so) 这是什么问题，是需要更新这个glibc吗，怎么操作啊

在HashMap中使用中老是遇到get方法返回的null的情况，但是对应关键字中确实是有值的。 我尝试过下面两种方法，均有时凑效，有时不凑效： 方法A for (HashMap.Entry<String, List<Channel>> entry : manager.entrySet()) { if (entry.getKey()!= senderId)continue; List<Channel> temp1=entry.getValue(); return temp1; } 遍历。有时能取到值，有时取不到。 方法B manager.get(senderId) 直接get，有时能取到值，有时取不到。   最后，我使用了这种方法，暂时解决了问题，但不确定会不会遇到新的问题 public static List<Channel> get(String senderId) { for (HashMap.Entry<String, List<Channel>> entry : manager.entrySet()) { if (entry.getKey()!= senderId)continue; List<Channel> temp1=entry.getValue(); return temp1; } return manager.get(senderId); } 非常无奈，马上答辩了，项目还没做完，看haspmap源码又看不懂，现在也没时间看。 希望大佬能不能通俗易通的讲一讲这到底是怎么回事，或者还有没有更稳定的haspMap的取值方法。谢谢！

kafka在--spring.cloud.bootstrap.name=bootstrap-dev方式启动下取不到监听数据

目前在用Eclipse进行java编程。有时需要在run configuration的Arguments里输入arguments，来运行java程序。但我发现，当我在Java中打开一个新的java项目时，这个新的JAVA项目中的Arguments还是旧项目的Arguments。Netbeans里面每个arguments是跟着项目走的，但是我不知道Eclipse是不是也是这样呢? 怎样才能保证，我每次打开一个新的项目，里面的arguments是新的项目的，不是旧的项目的呢？ 还有一个问题就是，有没有可能把arguments内容写在一个txt文件里，每次运行程序时，通过代码调取txt文件作为Arguments？