Я использую реализацию Persistent Manager на сервере Tomcat с JDBC-хранилищем, которое хранит данные сеанса в таблице БД вместо хранения в Tomcat. Я настроил свой файл context.xml, как показано ниже, для моей базы данных Oracle.
<Valve className="org.apache.catalina.valves.PersistentValve" />
<Resource name="jdbc/mydb" type="javax.sql.DataSource"
maxActive="50" maxIdle="20" maxWait="5000" validationQuery="select 1 from dual"
removeAbandoned="true" logAbandoned="true" driverClassName="oracle.jdbc.driver.OracleDriver"
username="myusername" password="mypassword"
url="jdbc:oracle:thin:@192.168.1.63:1521/orcl" />
<Manager className="org.apache.catalina.session.PersistentManager"
distributable="true" processExpiresFrequency="3" maxIdleBackup="1" saveOnRestart='false'>
<Store className="org.apache.catalina.session.JDBCStore"
dataSourceName="jdbc/mydb"
sessionAppCol="app_name" sessionDataCol="session_data" sessionIdCol="session_id"
sessionLastAccessedCol="last_access" sessionMaxInactiveCol="max_inactive"
sessionTable="tomcat_sessions" sessionValidCol="valid_session" />
</Manager>
Данные сеанса сохраняются в таблице БД в порядке исключения. Но теперь я хочу сделать то же самое для моей БД MySQL, и я настроил так же, как и для БД Oracle. Внесены только необходимые изменения для MySQL в Resource, как показано ниже. Но это бросает NullPointerException.
<Resource name="jdbc/mydb" type="javax.sql.DataSource"
maxActive="150" maxIdle="100" maxWait="5000" validationQuery="select 1"
removeAbandoned="true" logAbandoned="true" driverClassName="com.mysql.jdbc.Driver"
username="myusername" password="mypassword"
url="jdbc:mysql://192.168.1.205:2222/mydbname" />
Трассировка стека:
SEVERE: Error manager.start()
java.lang.NullPointerException
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:195)
at org.apache.catalina.session.JDBCStore.open(JDBCStore.java:861)
at org.apache.catalina.session.JDBCStore.getConnection(JDBCStore.java:833)
at org.apache.catalina.session.JDBCStore.start(JDBCStore.java:968)
at org.apache.catalina.session.PersistentManagerBase.start(PersistentManagerBase.java:995)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4714)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:799)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:779)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:601)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1079)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:1002)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:506)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1317)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:324)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:142)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1065)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:840)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:463)
at org.apache.catalina.core.StandardService.start(StandardService.java:525)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:754)
at org.apache.catalina.startup.Catalina.start(Catalina.java:595)
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 org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
May 12, 2019 2:32:07 PM org.apache.catalina.core.StandardContext start
SEVERE: Context [] startup failed due to previous errors
May 12, 2019 2:32:07 PM org.apache.coyote.http11.Http11Protocol start
INFO: Starting Coyote HTTP/1.1 on http-8090
May 12, 2019 2:32:07 PM org.apache.jk.common.ChannelSocket init
INFO: JK: ajp13 listening on /0.0.0.0:8011
May 12, 2019 2:32:07 PM org.apache.jk.server.JkMain start
INFO: Jk running ID=0 time=0/22 config=null
May 12, 2019 2:32:07 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 262912 ms
Exception in thread "Quartz Scheduler [SCHEDULERS]" May 12, 2019 2:33:58 PM org.apache.catalina.loader.WebappClassLoader loadClass
INFO: Illegal access: this web application instance has been stopped already. Could not load org.quartz.utils.ExceptionHelper. The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact.
java.lang.IllegalStateException
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1566)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526)
at org.quartz.SchedulerException.getUnderlyingException(SchedulerException.java:169)
at org.quartz.SchedulerException.toString(SchedulerException.java:265)
at java.lang.String.valueOf(String.java:2849)
at java.lang.StringBuilder.append(StringBuilder.java:128)
at org.springframework.core.NestedExceptionUtils.buildMessage(NestedExceptionUtils.java:47)
at org.springframework.core.NestedRuntimeException.getMessage(NestedRuntimeException.java:74)
at java.lang.Throwable.getLocalizedMessage(Throwable.java:391)
at java.lang.Throwable.toString(Throwable.java:480)
at java.lang.String.valueOf(String.java:2849)
at java.io.PrintStream.println(PrintStream.java:821)
at org.apache.tomcat.util.log.SystemLogHandler.println(SystemLogHandler.java:242)
at java.lang.Throwable$WrappedPrintStream.println(Throwable.java:748)
at java.lang.Throwable.printStackTrace(Throwable.java:655)
at java.lang.Throwable.printStackTrace(Throwable.java:643)
at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:1061)
at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:1052)
at java.lang.Thread.dispatchUncaughtException(Thread.java:1986)
Exception: java.lang.NoClassDefFoundError thrown from the UncaughtExceptionHandler in thread "Quartz Scheduler [SCHEDULERS]"
Exception in thread "Quartz Scheduler [SCHEDULERS]"
Exception: java.lang.NoClassDefFoundError thrown from the UncaughtExceptionHandler in thread "Quartz Scheduler [SCHEDULERS]"