The problem of switch flowable ui applications to mysql

Hi,
I tried to switch flowable ui applications to mysql , but I found that using mysql-connector-java-6.x.jar would cause exceptions when restart the application. If I restart flowable ui after dropped all tables ,then it’'s normal.
When using mysql-connector-java-5.1.42.jar,all is normal.
What’s the reason caused ?
Is liquibase or mysql-connector-java?

exceptions when using mysql-connector-java-6.x.jar:
08:12:23,681 [localhost-startStop-1] WARN org.springframework.web.context.support.AnnotationConfigWebApplicationContext - Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘liquibase’ defined in class org.flowable.admin.conf.DatabaseConfiguration: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [liquibase.Liquibase]: Factory method ‘liquibase’ threw exception; nested exception is org.flowable.app.service.exception.InternalServerErrorException: Error creating liquibase database

Is that all stacktrace there is ? I’d expect a root cause that’s different from the InternalServerErrorException.
What database version are you connecting to?

Hi,
mysql version is mysql-5.7.18-winx64
All stacktrace here when using mysql-connector-java-6.x.jar:

  • 21-Jun-2017 09:41:18.759 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Server version: Apache Tomcat/8.5.15
    21-Jun-2017 09:41:18.764 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Server built: May 5 2017 11:03:04 UTC
    21-Jun-2017 09:41:18.765 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Server number: 8.5.15.0
    21-Jun-2017 09:41:18.765 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log OS Name: Windows 10
    21-Jun-2017 09:41:18.765 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log OS Version: 10.0
    21-Jun-2017 09:41:18.765 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Architecture: amd64
    21-Jun-2017 09:41:18.766 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Java Home: D:\Java\jdk1.8.0_121\jre
    21-Jun-2017 09:41:18.766 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Version: 1.8.0_121-b13
    21-Jun-2017 09:41:18.767 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Vendor: Oracle Corporation
    21-Jun-2017 09:41:18.767 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_BASE: D:\flowable\apache-tomcat-8.5.15test
    21-Jun-2017 09:41:18.767 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_HOME: D:\flowable\apache-tomcat-8.5.15test
    21-Jun-2017 09:41:18.768 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.config.file=D:\flowable\apache-tomcat-8.5.15test\conf\logging.properties
    21-Jun-2017 09:41:18.769 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
    21-Jun-2017 09:41:18.769 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djdk.tls.ephemeralDHKeySize=2048
    21-Jun-2017 09:41:18.769 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.protocol.handler.pkgs=org.apache.catalina.webresources
    21-Jun-2017 09:41:18.769 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.base=D:\flowable\apache-tomcat-8.5.15test
    21-Jun-2017 09:41:18.770 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.home=D:\flowable\apache-tomcat-8.5.15test
    21-Jun-2017 09:41:18.771 信息 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.io.tmpdir=D:\flowable\apache-tomcat-8.5.15test\temp
    21-Jun-2017 09:41:18.771 信息 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent Loaded APR based Apache Tomcat Native library [1.2.12] using APR version [1.5.2].
    21-Jun-2017 09:41:18.772 信息 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].
    21-Jun-2017 09:41:18.773 信息 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR/OpenSSL configuration: useAprConnector [false], useOpenSSL [true]
    21-Jun-2017 09:41:19.665 信息 [main] org.apache.catalina.core.AprLifecycleListener.initializeSSL OpenSSL successfully initialized [OpenSSL 1.0.2k 26 Jan 2017]
    21-Jun-2017 09:41:19.843 信息 [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler [“http-nio-8080”]
    21-Jun-2017 09:41:20.022 信息 [main] org.apache.tomcat.util.net.NioSelectorPool.getSharedSelector Using a shared selector for servlet write/read
    21-Jun-2017 09:41:20.025 信息 [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler [“ajp-nio-8009”]
    21-Jun-2017 09:41:20.028 信息 [main] org.apache.tomcat.util.net.NioSelectorPool.getSharedSelector Using a shared selector for servlet write/read
    21-Jun-2017 09:41:20.028 信息 [main] org.apache.catalina.startup.Catalina.load Initialization processed in 2069 ms
    21-Jun-2017 09:41:20.104 信息 [main] org.apache.catalina.core.StandardService.startInternal Starting service [Catalina]
    21-Jun-2017 09:41:20.104 信息 [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/8.5.15
    21-Jun-2017 09:41:20.113 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [D:\flowable\apache-tomcat-8.5.15test\webapps\flowable-admin]
    21-Jun-2017 09:41:21.873 信息 [localhost-startStop-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.
    09:41:23,533 [localhost-startStop-1] INFO org.flowable.admin.conf.DatabaseConfiguration - Configuring Datasource
    09:41:23,567 [localhost-startStop-1] INFO org.flowable.admin.conf.DatabaseConfiguration - Configuring Datasource with following properties (omitted password for security)
    09:41:23,572 [localhost-startStop-1] INFO org.flowable.admin.conf.DatabaseConfiguration - datasource driver : com.mysql.jdbc.Driver
    09:41:23,573 [localhost-startStop-1] INFO org.flowable.admin.conf.DatabaseConfiguration - datasource url : jdbc:mysql://localhost:3306/flowable?serverTimezone=UTC&characterEncoding=utf8&useUnicode=true&useSSL=false&autoReconnect=true
    09:41:23,573 [localhost-startStop-1] INFO org.flowable.admin.conf.DatabaseConfiguration - datasource user name : flowable
    09:41:23,573 [localhost-startStop-1] INFO org.flowable.admin.conf.DatabaseConfiguration - Min pool size | Max pool size | acquire increment : 5 | 20 | 1
    09:41:23,716 [MLog-Init-Reporter] INFO com.mchange.v2.log.MLog - MLog clients using slf4j logging.
    09:41:23,802 [localhost-startStop-1] INFO com.mchange.v2.c3p0.C3P0Registry - Initializing c3p0-0.9.5.2 [built 08-December-2015 22:06:04 -0800; debug? true; trace: 10]
    09:41:25,625 [localhost-startStop-1] INFO com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource - Initializing c3p0 pool… com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 1, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, contextClassLoaderSource -> caller, dataSourceName -> 1hge1er9o1jkupjf18vxdfb|589fe141, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> com.mysql.jdbc.Driver, extensions -> {}, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, forceSynchronousCheckins -> false, forceUseNamedDriverClass -> false, identityToken -> 1hge1er9o1jkupjf18vxdfb|589fe141, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:mysql://localhost:3306/flowable?serverTimezone=UTC&characterEncoding=utf8&useUnicode=true&useSSL=false&autoReconnect=true, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 1800, maxIdleTimeExcessConnections -> 1800, maxPoolSize -> 20, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 5, numHelperThreads -> 3, preferredTestQuery -> null, privilegeSpawnedThreads -> false, properties -> {user=******, password=******}, propertyCycle -> 0, statementCacheNumDeferredCloseThreads -> 0, testConnectionOnCheckin -> true, testConnectionOnCheckout -> true, unreturnedConnectionTimeout -> 0, userOverrides -> {}, usesTraditionalReflectiveProxies -> false ]
    09:41:25,661 [localhost-startStop-1] WARN com.mchange.v2.resourcepool.BasicResourcePool - Bad pool size config, start 3 < min 5. Using 5 as start.
    Loading class com.mysql.jdbc.Driver'. This is deprecated. The new driver class iscom.mysql.cj.jdbc.Driver’. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.
    INFO 17-6-21 上午9:41: liquibase: Successfully acquired change log lock
    INFO 17-6-21 上午9:41: liquibase: Successfully released change log lock
    09:41:27,934 [localhost-startStop-1] WARN org.springframework.web.context.support.AnnotationConfigWebApplicationContext - Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘liquibase’ defined in class org.flowable.admin.conf.DatabaseConfiguration: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [liquibase.Liquibase]: Factory method ‘liquibase’ threw exception; nested exception is org.flowable.app.service.exception.InternalServerErrorException: Error creating liquibase database
    21-Jun-2017 09:41:28.011 严重 [localhost-startStop-1] org.apache.catalina.core.StandardContext.startInternal One or more listeners failed to start. Full details will be found in the appropriate container log file
    21-Jun-2017 09:41:28.017 严重 [localhost-startStop-1] org.apache.catalina.core.StandardContext.startInternal Context [/flowable-admin] startup failed due to previous errors
    09:41:28,020 [localhost-startStop-1] INFO org.flowable.admin.conf.WebConfigurer - Destroying Web application
    21-Jun-2017 09:41:28.026 警告 [localhost-startStop-1] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesThreads The web application [flowable-admin] appears to have started a thread named [Abandoned connection cleanup thread] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
    java.lang.Object.wait(Native Method)
    java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:143)
    com.mysql.cj.jdbc.AbandonedConnectionCleanupThread.run(AbandonedConnectionCleanupThread.java:43)
    21-Jun-2017 09:41:28.036 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [D:\flowable\apache-tomcat-8.5.15test\webapps\flowable-admin] has finished in [7,922] ms
    21-Jun-2017 09:41:28.036 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [D:\flowable\apache-tomcat-8.5.15test\webapps\flowable-idm]
    09:41:30,794 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - Configuring Datasource
    09:41:30,834 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - Configuring Datasource with following properties (omitted password for security)
    09:41:30,840 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - datasource driver : com.mysql.jdbc.Driver
    09:41:30,842 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - datasource url : jdbc:mysql://localhost:3306/flowable?serverTimezone=UTC&characterEncoding=utf8&useUnicode=true&useSSL=false&autoReconnect=true
    09:41:30,845 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - datasource user name : flowable
    09:41:30,847 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - Min pool size | Max pool size | acquire increment : 10 | 100 | 5
    09:41:30,939 [MLog-Init-Reporter] INFO com.mchange.v2.log.MLog - MLog clients using slf4j logging.
    09:41:31,037 [localhost-startStop-1] INFO com.mchange.v2.c3p0.C3P0Registry - Initializing c3p0-0.9.5.2 [built 08-December-2015 22:06:04 -0800; debug? true; trace: 10]
    09:41:31,623 [localhost-startStop-1] INFO com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource - Initializing c3p0 pool… com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 5, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, contextClassLoaderSource -> caller, dataSourceName -> 1hge1er9o1jkuv46173689a|588b8ec1, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> com.mysql.jdbc.Driver, extensions -> {}, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, forceSynchronousCheckins -> false, forceUseNamedDriverClass -> false, identityToken -> 1hge1er9o1jkuv46173689a|588b8ec1, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:mysql://localhost:3306/flowable?serverTimezone=UTC&characterEncoding=utf8&useUnicode=true&useSSL=false&autoReconnect=true, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 1800, maxIdleTimeExcessConnections -> 1800, maxPoolSize -> 100, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 10, numHelperThreads -> 3, preferredTestQuery -> null, privilegeSpawnedThreads -> false, properties -> {user=******, password=******}, propertyCycle -> 0, statementCacheNumDeferredCloseThreads -> 0, testConnectionOnCheckin -> true, testConnectionOnCheckout -> true, unreturnedConnectionTimeout -> 0, userOverrides -> {}, usesTraditionalReflectiveProxies -> false ]
    09:41:31,656 [localhost-startStop-1] WARN com.mchange.v2.resourcepool.BasicResourcePool - Bad pool size config, start 3 < min 10. Using 10 as start.
    09:41:32,347 [localhost-startStop-1] INFO org.flowable.idm.engine.impl.IdmEngineImpl - IdmEngine default created
    21-Jun-2017 09:41:35.200 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [D:\flowable\apache-tomcat-8.5.15test\webapps\flowable-idm] has finished in [7,164] ms
    21-Jun-2017 09:41:35.205 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [D:\flowable\apache-tomcat-8.5.15test\webapps\flowable-modeler]
    09:41:36,791 [localhost-startStop-1] INFO org.springframework.web.context.support.AnnotationConfigWebApplicationContext - Refreshing Root WebApplicationContext: startup date [Wed Jun 21 09:41:36 CST 2017]; root of context hierarchy
    09:41:37,066 [localhost-startStop-1] INFO org.springframework.web.context.support.AnnotationConfigWebApplicationContext - Registering annotated classes: [class org.flowable.app.conf.ApplicationConfiguration]
    09:41:38,726 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - Configuring Datasource
    09:41:38,770 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - Configuring Datasource with following properties (omitted password for security)
    09:41:38,774 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - datasource driver : com.mysql.jdbc.Driver
    09:41:38,775 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - datasource url : jdbc:mysql://localhost:3306/flowable?serverTimezone=UTC&characterEncoding=utf8&useUnicode=true&useSSL=false&autoReconnect=true
    09:41:38,776 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - datasource user name : flowable
    09:41:38,777 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - Min pool size | Max pool size | acquire increment : 10 | 100 | 5
    09:41:38,847 [MLog-Init-Reporter] INFO com.mchange.v2.log.MLog - MLog clients using slf4j logging.
    09:41:38,920 [localhost-startStop-1] INFO com.mchange.v2.c3p0.C3P0Registry - Initializing c3p0-0.9.5.2 [built 08-December-2015 22:06:04 -0800; debug? true; trace: 10]
    09:41:38,922 [localhost-startStop-1] WARN com.mchange.v2.c3p0.management.ActiveManagementCoordinator - A C3P0Registry mbean is already registered. This probably means that an application using c3p0 was undeployed, but not all PooledDataSources were closed prior to undeployment. This may lead to resource leaks over time. Please take care to close all PooledDataSources.
    09:41:39,054 [localhost-startStop-1] INFO com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource - Initializing c3p0 pool… com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 5, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, contextClassLoaderSource -> caller, dataSourceName -> 1hge1er9o1jkv17e15qdp2v|8e12146, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> com.mysql.jdbc.Driver, extensions -> {}, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, forceSynchronousCheckins -> false, forceUseNamedDriverClass -> false, identityToken -> 1hge1er9o1jkv17e15qdp2v|8e12146, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:mysql://localhost:3306/flowable?serverTimezone=UTC&characterEncoding=utf8&useUnicode=true&useSSL=false&autoReconnect=true, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 1800, maxIdleTimeExcessConnections -> 1800, maxPoolSize -> 100, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 10, numHelperThreads -> 3, preferredTestQuery -> null, privilegeSpawnedThreads -> false, properties -> {user=******, password=******}, propertyCycle -> 0, statementCacheNumDeferredCloseThreads -> 0, testConnectionOnCheckin -> true, testConnectionOnCheckout -> true, unreturnedConnectionTimeout -> 0, userOverrides -> {}, usesTraditionalReflectiveProxies -> false ]
    09:41:39,084 [localhost-startStop-1] WARN com.mchange.v2.resourcepool.BasicResourcePool - Bad pool size config, start 3 < min 10. Using 10 as start.
    09:41:39,119 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - database product name: 'MySQL’
    09:41:39,123 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - using database type: mysql
    09:41:39,834 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - Configuring Liquibase
    INFO 17-6-21 上午9:41: liquibase: Successfully acquired change log lock
    INFO 17-6-21 上午9:41: liquibase: Successfully released change log lock
    09:41:41,866 [localhost-startStop-1] WARN org.springframework.web.context.support.AnnotationConfigWebApplicationContext - Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘liquibase’ defined in class path resource [org/flowable/app/conf/DatabaseConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [liquibase.Liquibase]: Factory method ‘liquibase’ threw exception; nested exception is org.flowable.app.service.exception.InternalServerErrorException: Error creating liquibase database
    21-Jun-2017 09:41:41.922 严重 [localhost-startStop-1] org.apache.catalina.core.StandardContext.startInternal One or more listeners failed to start. Full details will be found in the appropriate container log file
    21-Jun-2017 09:41:41.927 严重 [localhost-startStop-1] org.apache.catalina.core.StandardContext.startInternal Context [/flowable-modeler] startup failed due to previous errors
    09:41:41,930 [localhost-startStop-1] INFO org.flowable.app.servlet.WebConfigurer - Destroying Web application
    21-Jun-2017 09:41:41.942 警告 [localhost-startStop-1] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesThreads The web application [flowable-modeler] appears to have started a thread named [Resource Destroyer in BasicResourcePool.close()] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
    com.mysql.cj.jdbc.ConnectionImpl.close(ConnectionImpl.java:1164)
    com.mchange.v2.c3p0.impl.NewPooledConnection.close(NewPooledConnection.java:642)
    com.mchange.v2.c3p0.impl.NewPooledConnection.closeMaybeCheckedOut(NewPooledConnection.java:255)
    com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.destroyResource(C3P0PooledConnectionPool.java:622)
    com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask.run(BasicResourcePool.java:1076)
    com.mchange.v2.resourcepool.BasicResourcePool.destroyResource(BasicResourcePool.java:1101)
    com.mchange.v2.resourcepool.BasicResourcePool.destroyResource(BasicResourcePool.java:1062)
    com.mchange.v2.resourcepool.BasicResourcePool.access$100(BasicResourcePool.java:44)
    com.mchange.v2.resourcepool.BasicResourcePool$5.run(BasicResourcePool.java:1316)
    21-Jun-2017 09:41:41.951 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [D:\flowable\apache-tomcat-8.5.15test\webapps\flowable-modeler] has finished in [6,747] ms
    21-Jun-2017 09:41:41.956 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [D:\flowable\apache-tomcat-8.5.15test\webapps\flowable-task]
    09:41:45,143 [localhost-startStop-1] INFO org.flowable.app.conf.AsyncConfiguration - Creating Async Task Executor
    09:41:45,523 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - Configuring Datasource
    09:41:45,555 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - Configuring Datasource with following properties (omitted password for security)
    09:41:45,560 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - datasource driver : com.mysql.jdbc.Driver
    09:41:45,560 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - datasource url : jdbc:mysql://localhost:3306/flowable?serverTimezone=UTC&characterEncoding=utf8&useUnicode=true&useSSL=false&autoReconnect=true
    09:41:45,561 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - datasource user name : flowable
    09:41:45,562 [localhost-startStop-1] INFO org.flowable.app.conf.DatabaseConfiguration - Min pool size | Max pool size | acquire increment : 10 | 100 | 5
    09:41:45,630 [MLog-Init-Reporter] INFO com.mchange.v2.log.MLog - MLog clients using slf4j logging.
    09:41:45,714 [localhost-startStop-1] INFO com.mchange.v2.c3p0.C3P0Registry - Initializing c3p0-0.9.5.2 [built 08-December-2015 22:06:04 -0800; debug? true; trace: 10]
    09:41:47,010 [localhost-startStop-1] INFO org.flowable.engine.impl.cfg.ProcessEngineConfigurationImpl - Found 3 Process Engine Configurators in total:
    09:41:47,010 [localhost-startStop-1] INFO org.flowable.engine.impl.cfg.ProcessEngineConfigurationImpl - class org.flowable.form.spring.configurator.SpringFormEngineConfigurator (priority:10000)
    09:41:47,012 [localhost-startStop-1] INFO org.flowable.engine.impl.cfg.ProcessEngineConfigurationImpl - class org.flowable.dmn.spring.configurator.SpringDmnEngineConfigurator (priority:10000)
    09:41:47,015 [localhost-startStop-1] INFO org.flowable.engine.impl.cfg.ProcessEngineConfigurationImpl - class org.flowable.content.spring.configurator.SpringContentEngineConfigurator (priority:10000)
    09:41:47,016 [localhost-startStop-1] INFO org.flowable.engine.impl.cfg.ProcessEngineConfigurationImpl - Executing beforeInit() of class org.flowable.form.spring.configurator.SpringFormEngineConfigurator (priority:10000)
    09:41:47,019 [localhost-startStop-1] INFO org.flowable.engine.impl.cfg.ProcessEngineConfigurationImpl - Executing beforeInit() of class org.flowable.dmn.spring.configurator.SpringDmnEngineConfigurator (priority:10000)
    09:41:47,021 [localhost-startStop-1] INFO org.flowable.engine.impl.cfg.ProcessEngineConfigurationImpl - Executing beforeInit() of class org.flowable.content.spring.configurator.SpringContentEngineConfigurator (priority:10000)
    09:41:47,159 [localhost-startStop-1] INFO com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource - Initializing c3p0 pool… com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 5, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, contextClassLoaderSource -> caller, dataSourceName -> 1hge1er9o1jkv6g31j4nvlm|210d42e3, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> com.mysql.jdbc.Driver, extensions -> {}, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, forceSynchronousCheckins -> false, forceUseNamedDriverClass -> false, identityToken -> 1hge1er9o1jkv6g31j4nvlm|210d42e3, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:mysql://localhost:3306/flowable?serverTimezone=UTC&characterEncoding=utf8&useUnicode=true&useSSL=false&autoReconnect=true, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 1800, maxIdleTimeExcessConnections -> 1800, maxPoolSize -> 100, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 10, numHelperThreads -> 3, preferredTestQuery -> null, privilegeSpawnedThreads -> false, properties -> {user=******, password=******}, propertyCycle -> 0, statementCacheNumDeferredCloseThreads -> 0, testConnectionOnCheckin -> true, testConnectionOnCheckout -> true, unreturnedConnectionTimeout -> 0, userOverrides -> {}, usesTraditionalReflectiveProxies -> false ]
    09:41:47,189 [localhost-startStop-1] WARN com.mchange.v2.resourcepool.BasicResourcePool - Bad pool size config, start 3 < min 10. Using 10 as start.
    09:41:48,557 [localhost-startStop-1] INFO org.flowable.engine.impl.cfg.ProcessEngineConfigurationImpl - Executing configure() of class org.flowable.form.spring.configurator.SpringFormEngineConfigurator (priority:10000)
    INFO 17-6-21 上午9:41: liquibase: Successfully acquired change log lock
    INFO 17-6-21 上午9:41: liquibase: Successfully released change log lock
    09:41:50,993 [localhost-startStop-1] WARN org.springframework.web.context.support.AnnotationConfigWebApplicationContext - Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘deploymentServiceImpl’: Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: protected org.flowable.engine.RepositoryService org.flowable.app.service.runtime.DeploymentServiceImpl.repositoryService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘repositoryService’ defined in class path resource [org/flowable/app/conf/FlowableEngineConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.flowable.engine.RepositoryService]: Factory method ‘repositoryService’ threw exception; nested exception is java.lang.RuntimeException: org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘processEngine’: FactoryBean threw exception on object creation; nested exception is org.flowable.engine.common.api.FlowableException: Error initialising form data schema
    21-Jun-2017 09:41:50.998 严重 [localhost-startStop-1] org.apache.catalina.core.StandardContext.startInternal One or more listeners failed to start. Full details will be found in the appropriate container log file
    21-Jun-2017 09:41:50.999 严重 [localhost-startStop-1] org.apache.catalina.core.StandardContext.startInternal Context [/flowable-task] startup failed due to previous errors
    09:41:51,004 [localhost-startStop-1] INFO org.flowable.app.servlet.WebConfigurer - Destroying Web application
    21-Jun-2017 09:41:51.007 严重 [localhost-startStop-1] org.apache.catalina.loader.WebappClassLoaderBase.checkThreadLocalMapForLeaks The web application [flowable-task] created a ThreadLocal with key of type [java.lang.ThreadLocal] (value [java.lang.ThreadLocal@7a2b812f]) and a value of type [org.apache.ibatis.executor.ErrorContext] (value [
    The error may exist in org/flowable/db/mapping/entity/EventLogEntry.xml
    The error occurred while processing mapper_resultMap[eventLogEntryResultMap]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
    21-Jun-2017 09:41:51.010 信息 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [D:\flowable\apache-tomcat-8.5.15test\webapps\flowable-task] has finished in [9,054] ms
    21-Jun-2017 09:41:51.027 信息 [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler [“http-nio-8080”]
    21-Jun-2017 09:41:51.037 信息 [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler [“ajp-nio-8009”]
    21-Jun-2017 09:41:51.041 信息 [main] org.apache.catalina.startup.Catalina.start Server startup in 31012 ms

It seems the driver name has changed between the 5 and 6 MySQL driver: it should be com.mysql.cj.jdbc.Driver now. Did you do that?

(I’m not sure the 6.x versions of the MySQL driver are already useable, see https://dev.mysql.com/doc/relnotes/connector-j/6.0/en/news-6-0-6.html, where the 6.0.6 version is labeled as a ‘milestone’ release for ‘testing upcoming features’)

Thanks for your reply,
Yes ,I had used com.mysql.cj.jdbc.Driver,and got the exception .
May be the 6.x versions of the MySQL driver are not already useable,as you say.
I had switched to mysql-connector-java-5.1.42 and now everything is back to normal.