环境使用的是 Tomcat8.0， 导入的是 mysql-connector-java-5.1.47.jar 包，当然 mysql-connector-java-5.1.18.jar 也试过没用

链接数据库的配置：

工具链接mysql:

以下是报错的信息：

"E:\Program Files\apache\apache-tomcat-8.0.52\bin\catalina.bat" run
[2018-10-16 09:18:23,762] Artifact JDBCMessageBoard:war exploded: Waiting for server connection to start artifact deployment...
Using CATALINA_BASE:   "C:\Users\Administrator\.IntelliJIdea2018.1\system\tomcat\Unnamed_JDBCMessageBoard_2"
Using CATALINA_HOME:   "E:\Program Files\apache\apache-tomcat-8.0.52"
Using CATALINA_TMPDIR: "E:\Program Files\apache\apache-tomcat-8.0.52\temp"
Using JRE_HOME:        "E:\Program Files\Java\jdk1.8.0_171"
Using CLASSPATH:       "E:\Program Files\apache\apache-tomcat-8.0.52\bin\bootstrap.jar;E:\Program Files\apache\apache-tomcat-8.0.52\bin\tomcat-juli.jar"
16-Oct-2018 09:18:24.568 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Server version:        Apache Tomcat/8.0.52
16-Oct-2018 09:18:24.571 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Server built:          Apr 28 2018 16:24:29 UTC
16-Oct-2018 09:18:24.571 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Server number:         8.0.52.0
16-Oct-2018 09:18:24.571 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log OS Name:               Windows 7
16-Oct-2018 09:18:24.571 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log OS Version:            6.1
16-Oct-2018 09:18:24.571 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Architecture:          amd64
16-Oct-2018 09:18:24.571 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Java Home:             E:\Program Files\Java\jdk1.8.0_171\jre
16-Oct-2018 09:18:24.571 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Version:           1.8.0_171-b11
16-Oct-2018 09:18:24.571 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Vendor:            Oracle Corporation
16-Oct-2018 09:18:24.571 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_BASE:         C:\Users\Administrator\.IntelliJIdea2018.1\system\tomcat\Unnamed_JDBCMessageBoard_2
16-Oct-2018 09:18:24.572 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_HOME:         E:\Program Files\apache\apache-tomcat-8.0.52
16-Oct-2018 09:18:24.572 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.config.file=C:\Users\Administrator\.IntelliJIdea2018.1\system\tomcat\Unnamed_JDBCMessageBoard_2\conf\logging.properties
16-Oct-2018 09:18:24.572 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
16-Oct-2018 09:18:24.572 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote=
16-Oct-2018 09:18:24.573 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote.port=1099
16-Oct-2018 09:18:24.573 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote.ssl=false
16-Oct-2018 09:18:24.573 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote.authenticate=false
16-Oct-2018 09:18:24.573 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.rmi.server.hostname=127.0.0.1
16-Oct-2018 09:18:24.573 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djdk.tls.ephemeralDHKeySize=2048
16-Oct-2018 09:18:24.573 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.protocol.handler.pkgs=org.apache.catalina.webresources
16-Oct-2018 09:18:24.573 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dignore.endorsed.dirs=
16-Oct-2018 09:18:24.573 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.base=C:\Users\Administrator\.IntelliJIdea2018.1\system\tomcat\Unnamed_JDBCMessageBoard_2
16-Oct-2018 09:18:24.574 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.home=E:\Program Files\apache\apache-tomcat-8.0.52
16-Oct-2018 09:18:24.574 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.io.tmpdir=E:\Program Files\apache\apache-tomcat-8.0.52\temp
16-Oct-2018 09:18:24.574 信息 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent Loaded APR based Apache Tomcat Native library 1.2.16 using APR version 1.6.3.
16-Oct-2018 09:18:24.574 信息 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].
16-Oct-2018 09:18:25.404 信息 [main] org.apache.catalina.core.AprLifecycleListener.initializeSSL OpenSSL successfully initialized (OpenSSL 1.0.2m  2 Nov 2017)
16-Oct-2018 09:18:25.506 信息 [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["http-apr-8084"]
16-Oct-2018 09:18:25.514 信息 [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["ajp-apr-8009"]
16-Oct-2018 09:18:25.516 信息 [main] org.apache.catalina.startup.Catalina.load Initialization processed in 1268 ms
16-Oct-2018 09:18:25.541 信息 [main] org.apache.catalina.core.StandardService.startInternal Starting service Catalina
16-Oct-2018 09:18:25.541 信息 [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/8.0.52
16-Oct-2018 09:18:25.550 信息 [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["http-apr-8084"]
16-Oct-2018 09:18:25.563 信息 [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["ajp-apr-8009"]
16-Oct-2018 09:18:25.567 信息 [main] org.apache.catalina.startup.Catalina.start Server startup in 51 ms
Connected to server
[2018-10-16 09:18:25,906] Artifact JDBCMessageBoard:war exploded: Artifact is being deployed, please wait...
16-Oct-2018 09:18:26.690 信息 [RMI TCP Connection(3)-127.0.0.1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
Init ContextListener
[2018-10-16 09:18:26,780] Artifact JDBCMessageBoard:war exploded: Artifact is deployed successfully
[2018-10-16 09:18:26,781] Artifact JDBCMessageBoard:war exploded: Deploy took 875 milliseconds
创建数据库连接失败。
java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: NO)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1073)
	at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3609)
	at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3541)
	at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:943)
	at com.mysql.jdbc.MysqlIO.secureAuth411(MysqlIO.java:4113)
	at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1308)
	at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2336)
	at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2369)
	at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2153)
	at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:792)
	at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
	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 com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
	at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:381)
	at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:305)
	at java.sql.DriverManager.getConnection(DriverManager.java:664)
	at java.sql.DriverManager.getConnection(DriverManager.java:247)
	at com.imooc.jdbc.common.ConnectionUtil.getConnection(ConnectionUtil.java:39)
	at com.imooc.jdbc.dao.MessageDAO.getMessages(MessageDAO.java:55)
	at com.imooc.jdbc.service.MessageService.getMessages(MessageService.java:34)
	at com.imooc.jdbc.servlet.MessageListServlet.service(MessageListServlet.java:41)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at com.imooc.jdbc.filter.UserFilter.doFilter(UserFilter.java:30)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at com.imooc.jdbc.filter.CharsetEncodingFilter.doFilter(CharsetEncodingFilter.java:28)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:94)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:502)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1156)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:684)
	at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2527)
	at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2516)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:748)
16-Oct-2018 09:18:35.550 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory E:\Program Files\apache\apache-tomcat-8.0.52\webapps\manager
16-Oct-2018 09:18:35.586 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory E:\Program Files\apache\apache-tomcat-8.0.52\webapps\manager has finished in 35 ms