mysql - "java.sql.SQLException: No suitable driver found"即使 jar 文件位于正确的位置并且数据库连接成功

Question

我正在使用 JPA 和 Glassfish 以及 MySQL 数据库(用于学校项目)开发一个 java Web 应用程序，到目前为止我已经收到了 3 次相同的 sql 异常。第一次是因为驱动程序不在 glassfish/lib 中，第二次是因为我的电脑位于错误的网络上，因此无法连接到数据库(不知道为什么这会导致“未找到合适的驱动程序”)...

这一次，即使jar文件位于glassfish/lib文件夹中，我再次遇到相同的异常，并且当我ping它时，与数据库的连接成功。

我完全不知道为什么现在会发生这种情况，因为它今天早上正在工作，而且我没有修改任何配置文件......

任何关于为什么会发生这种情况的见解都将不胜感激。

这是我的项目层次结构:

这是驱动程序在我的 glassfish 文件夹中的位置:

如果您需要任何额外信息，请告诉我，我很乐意提供!

[编辑]如果有什么不同，我尝试过使用已弃用的 com.mysql.jdbc.Driver 和新的 com.mysql.cj.jdbc.Driver

[编辑2]根据@Billy Frost的要求，这是完整的堆栈跟踪(我第一次完全忘记包含它)

[2019-01-02T16:37:53.744+0100] [glassfish 4.1] [WARNING] [] [javax.enterprise.web] [tid: _ThreadID=29 _ThreadName=http-listener-1(2)] [timeMillis: 1546443473744] [levelValue: 900] [[
StandardWrapperValve[javax.ws.rs.core.Application]: Servlet.service() for servlet javax.ws.rs.core.Application threw exception
java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost:3306/shareloc
    at java.sql.DriverManager.getConnection(DriverManager.java:689)
    at java.sql.DriverManager.getConnection(DriverManager.java:208)
    at org.eclipse.persistence.sessions.DefaultConnector.connect(DefaultConnector.java:98)
    at org.eclipse.persistence.sessions.DatasourceLogin.connectToDatasource(DatasourceLogin.java:162)
    at org.eclipse.persistence.internal.sessions.DatabaseSessionImpl.setOrDetectDatasource(DatabaseSessionImpl.java:204)
    at org.eclipse.persistence.internal.sessions.DatabaseSessionImpl.loginAndDetectDatasource(DatabaseSessionImpl.java:741)
    at org.eclipse.persistence.internal.jpa.EntityManagerFactoryProvider.login(EntityManagerFactoryProvider.java:239)
    at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy(EntityManagerSetupImpl.java:685)
    at org.eclipse.persistence.internal.jpa.EntityManagerFactoryDelegate.getAbstractSession(EntityManagerFactoryDelegate.java:204)
    at org.eclipse.persistence.internal.jpa.EntityManagerFactoryDelegate.createEntityManagerImpl(EntityManagerFactoryDelegate.java:304)
    at org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.createEntityManagerImpl(EntityManagerFactoryImpl.java:336)
    at org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:302)
    at dao.DAOAbstractFacade.getEntityManager(DAOAbstractFacade.java:42)
    at dao.DAOAbstractFacade.find(DAOAbstractFacade.java:86)
    at controller.UserManager.createUser(UserManager.java:35)
    at paths.Authentification.signup(Authentification.java:62)
    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.glassfish.jersey.server.model.internal.ResourceMethodInvocationHandlerFactory$1.invoke(ResourceMethodInvocationHandlerFactory.java:81)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher$1.run(AbstractJavaResourceMethodDispatcher.java:151)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.invoke(AbstractJavaResourceMethodDispatcher.java:171)
    at org.glassfish.jersey.server.model.internal.JavaResourceMethodDispatcherProvider$ResponseOutInvoker.doDispatch(JavaResourceMethodDispatcherProvider.java:152)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.dispatch(AbstractJavaResourceMethodDispatcher.java:104)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:387)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:331)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:103)
    at org.glassfish.jersey.server.ServerRuntime$1.run(ServerRuntime.java:271)
    at org.glassfish.jersey.internal.Errors$1.call(Errors.java:271)
    at org.glassfish.jersey.internal.Errors$1.call(Errors.java:267)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:315)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:297)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:267)
    at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:297)
    at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:254)
    at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:1028)
    at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:372)
    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:381)
    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:344)
    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:221)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:415)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:282)
    at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:459)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:167)
    at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:201)
    at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:175)
    at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235)
    at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112)
    at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
    at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:561)
    at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:565)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:545)
    at java.lang.Thread.run(Thread.java:748)
]]

Answer 1

所以，事实证明 MySQL Server 8.0 实际上与 MySQL Connector/J 8.0.13 并不兼容，尽管它们都是最新版本...我最终将我的 MySQL 服务器降级到 5.5.62(这就是我在不同的测试服务器上工作)，当安装完成时，一切都像魅力一样工作......

非常感谢@Manish Bansal 让我走上了正确的道路!