Could not load driverClass com.mysql.jbdc.Driver,配置好jar了还是找不到

自学线上商城的java web 项目。今天一个下午都在调这个bug,也试过调试jar包,也有重新配置Tomcat与mysql的连接池
我也有把jdbc的包放在jdk的lib文件夹下,然后增加classpath,jre的ext都试过
还看了新的jdbc是com.mysql.cj.jdbc.Driver也试过,似乎都没什么用

在maven和Tomcat的列表里都有jdbc的jar包,包括我自己有新build path也增加了这些jar包,而且我把好几个版本的都放上去了(不知道会不会是这个影响,不过加了也删不掉),pom.xml里面配的是截图中的8.0.17

图片说明


如果需要更多信息我也可以再加,感激不尽

报错信息如下:**********

8月 02, 2019 11:30:38 下午 com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource getPoolManager
信息: Initializing c3p0 pool... com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 3, acquireRetryAttempts -> 2, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 10000, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, dataSourceName -> 1hge162a4n0lvdz1eiiv1j|6ccdb29f, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> com.mysql.jbdc.Driver, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, identityToken -> 1hge162a4n0lvdz1eiiv1j|6ccdb29f, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:mysql://localhost:3306/todoList?useUnicode=true&characterEncoding=utf8&serverTimezone=GMT&useSSL=false, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 0, maxIdleTimeExcessConnections -> 0, maxPoolSize -> 30, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 10, numHelperThreads -> 3, numThreadsAwaitingCheckoutDefaultUser -> 0, preferredTestQuery -> null, properties -> {password=******, user=******}, propertyCycle -> 0, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, unreturnedConnectionTimeout -> 0, usesTraditionalReflectiveProxies -> false ]
8月 02, 2019 11:30:38 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded
警告: Could not load driverClass com.mysql.jbdc.Driver
java.lang.ClassNotFoundException: com.mysql.jbdc.Driver
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    at java.base/java.lang.Class.forName0(Native Method)
    at java.base/java.lang.Class.forName(Class.java:332)
    at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:38 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded
警告: Could not load driverClass com.mysql.jbdc.Driver
java.lang.ClassNotFoundException: com.mysql.jbdc.Driver
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    at java.base/java.lang.Class.forName0(Native Method)
    at java.base/java.lang.Class.forName(Class.java:332)
    at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:38 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded
警告: Could not load driverClass com.mysql.jbdc.Driver
java.lang.ClassNotFoundException: com.mysql.jbdc.Driver
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    at java.base/java.lang.Class.forName0(Native Method)
    at java.base/java.lang.Class.forName(Class.java:332)
    at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded
警告: Could not load driverClass com.mysql.jbdc.Driver
java.lang.ClassNotFoundException: com.mysql.jbdc.Driver
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    at java.base/java.lang.Class.forName0(Native Method)
    at java.base/java.lang.Class.forName(Class.java:332)
    at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded
警告: Could not load driverClass com.mysql.jbdc.Driver
java.lang.ClassNotFoundException: com.mysql.jbdc.Driver
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    at java.base/java.lang.Class.forName0(Native Method)
    at java.base/java.lang.Class.forName(Class.java:332)
    at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded
警告: Could not load driverClass com.mysql.jbdc.Driver
java.lang.ClassNotFoundException: com.mysql.jbdc.Driver
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    at java.base/java.lang.Class.forName0(Native Method)
    at java.base/java.lang.Class.forName(Class.java:332)
    at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:40 下午 com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run
警告: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@40eddbb0 -- 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 (2). Last acquisition attempt exception: 
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown database 'todolist'
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
    at com.mysql.jdbc.Util.getInstance(Util.java:408)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:944)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3978)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3914)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:871)
    at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1714)
    at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1224)
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2199)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2230)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2025)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:778)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:40 下午 com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run
警告: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@45eae662 -- 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 (2). Last acquisition attempt exception: 
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown database 'todolist'
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
    at com.mysql.jdbc.Util.getInstance(Util.java:408)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:944)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3978)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3914)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:871)
    at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1714)
    at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1224)
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2199)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2230)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2025)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:778)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded
警告: Could not load driverClass com.mysql.jbdc.Driver
java.lang.ClassNotFoundException: com.mysql.jbdc.Driver
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    at java.base/java.lang.Class.forName0(Native Method)
    at java.base/java.lang.Class.forName(Class.java:332)
    at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:40 下午 com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run
警告: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@6f8071b9 -- 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 (2). Last acquisition attempt exception: 
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown database 'todolist'
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
    at com.mysql.jdbc.Util.getInstance(Util.java:408)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:944)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3978)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3914)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:871)
    at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1714)
    at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1224)
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2199)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2230)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2025)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:778)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded
警告: Could not load driverClass com.mysql.jbdc.Driver
java.lang.ClassNotFoundException: com.mysql.jbdc.Driver
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    at java.base/java.lang.Class.forName0(Native Method)
    at java.base/java.lang.Class.forName(Class.java:332)
    at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded
警告: Could not load driverClass com.mysql.jbdc.Driver
java.lang.ClassNotFoundException: com.mysql.jbdc.Driver
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
    at java.base/java.lang.Class.forName0(Native Method)
    at java.base/java.lang.Class.forName(Class.java:332)
    at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
    at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)


4个回答

toomanyhair
toomanyhair 这个空格我昨天也检查过了,没有空格的,不过还是谢谢啦
10 个月之前 回复

把引用的驱动包放在 web 的 lib 目录下试试。

是c3p0包太老了,当时是照抄的代码,不支持现在的jdk12,更新一下就好了

不过还有别的问题,debug之路漫漫

驱动名称换成com.mysql.cj.jdbc.Driver。以前老版本的驱动没有cj包

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com.mysql.jdbc.Driver 为啥没有实现java.sql.Driver#getParentLogger()方法但是编译确不报错,有点费解~ 求大神指点迷津~

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八月 23, 2017 4:01:37 下午 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet [SpringMVC] in context with path [/liuyg] threw exception [Request processing failed; nested exception is org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create JDBC driver of class 'com.mysql.jdbc.Driver' for connect URL 'jdbc:mysql:127.0.0.1:3306/tjfx' ### The error may exist in file [D:\tomcat - liuyg\tomcat-7.0.81\webapps\liuyg\WEB-INF\classes\com\Mapping\xt_userMapper.xml] ### The error may involve com.Dao.xt_userMapper.selectByPrimaryKey ### The error occurred while executing a query ### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create JDBC driver of class 'com.mysql.jdbc.Driver' for connect URL 'jdbc:mysql:127.0.0.1:3306/tjfx'] with root cause java.sql.SQLException: No suitable driver 配置文件如下 jdbc.properties --------- jdbc.driver=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql:127.0.0.1:3306/tjfx jdbc.username=root jdbc.password=root #定义初始连接数 jdbc.initialSize=0 #定义最大连接数 jdbc.maxActive=20 #定义最大空闲 jdbc.maxIdle=20 #定义最小空闲 jdbc.minIdle=1 #定义最长等待时间 jdbc.maxWait=600000 ---------- spring-mvc.xml ------------ <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- 自动扫描该包,使SpringMVC认为包下用了@controller注解的类是控制器 --> <context:component-scan base-package="com" /> <!--避免IE执行AJAX时,返回JSON出现下载文件 --> <bean id="mappingJacksonHttpMessageConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"> <property name="supportedMediaTypes"> <list> <value>text/html;charset=UTF-8</value> </list> </property> </bean> <!-- 启动SpringMVC的注解功能,完成请求和注解POJO的映射 --> <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"> <property name="messageConverters"> <list> <ref bean="mappingJacksonHttpMessageConverter" /> <!-- JSON转换器 --> </list> </property> </bean> <!-- 定义跳转的文件的前后缀 ,视图模式配置 --> <!-- <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> --> <!-- <property name="prefix" value="/WEB-INF/welcome/" /> --> <!-- <property name="suffix" value=".htm" /> --> <!-- </bean> --> <!-- 静态资源处理--> <mvc:default-servlet-handler/> <!-- 注解驱动--> <mvc:annotation-driven></mvc:annotation-driven> <!-- 配置文件上传,如果没有使用文件上传可以不用配置,当然如果不配,那么配置文件中也不必引入上传组件包 --> <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <!-- 默认编码 --> <property name="defaultEncoding" value="utf-8" /> <!-- 文件大小最大值 --> <property name="maxUploadSize" value="10485760000" /> <!-- 内存中的最大值 --> <property name="maxInMemorySize" value="40960" /> </bean> <!-- 视图模式配置,velocity配置文件--> <bean id="velocityConfig" class="org.springframework.web.servlet.view.velocity.VelocityConfigurer"> <property name="resourceLoaderPath" value="/welcome/" /> <property name="configLocation" value="classpath:velocity.properties" /> <property name="velocityProperties"> <props> <prop key="input.encoding">utf-8</prop> <prop key="output.encoding">utf-8</prop> </props> </property> </bean> <!-- 配置后缀 --> <bean id="velocityViewResolver" class="org.springframework.web.servlet.view.velocity.VelocityViewResolver"> <property name="suffix" value=".htm" /> <property name="contentType" value="text/html;charset=UTF-8"></property> </bean> <import resource="spring-mybatis.xml"/> </beans> --------------- spring-mybatis.xml ------------------ <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- 自动扫描 --> <context:component-scan base-package="com" /> <!-- 引入配置文件 --> <!-- 1.读取数据库配置文件 --> <context:property-placeholder location="classpath:jdbc.properties" system-properties-mode="NEVER"/> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${jdbc.driver}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <!-- 初始化连接大小 --> <property name="initialSize" value="${jdbc.initialSize}"></property> <!-- 连接池最大数量 --> <property name="maxActive" value="${jdbc.maxActive}"></property> <!-- 连接池最大空闲 --> <property name="maxIdle" value="${jdbc.maxIdle}"></property> <!-- 连接池最小空闲 --> <property name="minIdle" value="${jdbc.minIdle}"></property> <!-- 获取连接最大等待时间 --> <property name="maxWait" value="${jdbc.maxWait}"></property> </bean> <!-- spring和MyBatis完美整合,不需要mybatis的配置映射文件 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <!-- 自动扫描mapping.xml文件 --> <property name="mapperLocations" value="classpath:com/Mapping/*.xml"></property> </bean> <!-- DAO接口所在包名,Spring会自动查找其下的类 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com/Dao" /> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean> <!-- (事务管理)transaction manager, use JtaTransactionManager for global tx --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource" /> </bean> </beans> ----------------

Could not get JDBC Connection

org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot load JDBC driver class 'com.microsoft.sqlserver.jdbc.SQLServerDriver' ### The error may exist in cn/drzk/wanda/cinema/dao/form/dao/TicketsFromDao.java (best guess) ### The error may involve cn.drzk.wanda.cinema.dao.form.dao.TicketsFromDao.count ### The error occurred while executing a query ### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot load JDBC driver class 'com.microsoft.sqlserver.jdbc.SQLServerDriver'

spring 中mysql驱动不能加载问题

各位大佬,今天我遇到一个问题,加载驱动时报不能加载问题,这是在application.properties文件中配置的 ![图片说明](https://img-ask.csdn.net/upload/201712/02/1512197333_105625.jpeg) 如果是用代码加载的话,则不报错,请问是什么原因 ![图片说明](https://img-ask.csdn.net/upload/201712/02/1512197405_842608.jpeg) 我最终解决的办法是将driver-class-name改为driverClassName 我尝试了很多次,不知道原因是什么,这样写没错,如果写driver-class-name则报错 #this method will report the driver can not load the exception #spring.datasource.driver-class-name= com.mysql.jdbc.Driver spring.datasource.driverClassName=com.mysql.jdbc.Driver

通过JDBC驱动连接Hive操作失败

hive版本:1.2.1 Hive.java程序片段: Class.forName("org.apache.hive.jdbc.HiveDriver"); 在centos上,通过javac -classpath对Hive.java 编译。相应的jar:hive-jdbc,hive-exec,hive-metastore 放在-classpath后面了。 编译成功; 通过jar cvf 打包成功为hive.jar. 然后通过 hadoop jar hive.jar com.aturbo.hadoop.Hive执行的时候,以后报下面的错: Exception in thread "main" java.lang.ClassNotFoundException: org.apache.hive.jdbc.HiveDriver at java.net.URLClassLoader$1.run(URLClassLoader.java:366) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:425) at java.lang.ClassLoader.loadClass(ClassLoader.java:358) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:195) at com.aturbo.hadoop.Hive.main(Hive.java:12) 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.hadoop.util.RunJar.main(RunJar.java:160) 不知道什么原因,求大神帮忙!

报错了却运行了,这是怎么回事???

用的c3p0往数据库插入数据的时候,运行报错了 Could not load driverClass com.mysql.jdbc.driver,,,,但是数据添加成功了,这是什么原理???

JDBC连接Mysql出现问题!

Insert 类 调用 JdbcUtil类时出现异常,但代码没有红叉,请大神指教! //第一个类 package com.jdbc.util; import java.io.InputStream; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.Properties; public class JdbcUtil { //数据库的连接的URL private static String url = null; //数据库用户名 private static String user = null; //数据库密码 private static String password = null; //驱动程序类 private static String driverClass = null ; public static void main(String[] args) { //static { //注册驱动 try { //创建Properties对象,接入jdbc.properties配置文件 Properties prop = new Properties(); //使用类路径方式读取配置文件 InputStream in = JdbcUtil.class.getResourceAsStream("/jdbc.properties"); //加载文件 prop.load(in); //读取配置文件的内容 url = prop.getProperty("url"); user = prop.getProperty("user"); password = prop.getProperty("password"); driverClass = prop.getProperty("driverClass"); Class.forName(driverClass); System.out.println(url); System.out.println(user); System.out.println(password); System.out.println(driverClass); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); } } //获取连接方法 public static Connection getConn() { try { Connection conn = DriverManager.getConnection(url, user, password); return conn; } catch (SQLException e) { e.printStackTrace(); throw new RuntimeException(e); } } //释放资源方法 public static void close(ResultSet rs,Statement stmt,Connection conn) { if(rs != null) { try { rs.close(); } catch (SQLException e) { e.printStackTrace(); throw new RuntimeException(e); } } if(stmt != null) { try { stmt.close(); } catch (SQLException e) { e.printStackTrace(); throw new RuntimeException(e); } } if(conn != null) { try { conn.close(); } catch (SQLException e) { e.printStackTrace(); throw new RuntimeException(e); } } } } //jdbc.properties配置文件: url=jdbc:mysql://localhost:3306/test user=root password=root driverClass=com.mysql.jdbc.Driver //第二个类 package com.crud.util; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import com.jdbc.util.JdbcUtil; public class Insert { public static void main(String[] args) { test(); } public static void test() { Connection conn = null; PreparedStatement stmt =null; ResultSet rs = null ; try { //获取连接 conn = JdbcUtil.getConn(); String sql = "INSERT INTO student(id,name,age) VALUES(?,?,?)"; //创建prepareStatement对象 stmt = conn.prepareStatement(sql); //设置参数 stmt.setInt(1, 7); stmt.setString(2, "奥巴马"); stmt.setInt(3, 22); //发送参数到数据库 rs = stmt.executeQuery(); } catch (Exception e) { e.printStackTrace(); }finally { //关闭资源 JdbcUtil.close(rs, stmt, conn); } } } ![图片说明](https://img-ask.csdn.net/upload/201812/03/1543814539_630825.png)

java +mysql LOAD DATA INFILE mysql中执行正常,java报错???

LOAD DATA INFILE '/txt/test.txt' INTO TABLE test LINES TERMINATED BY '\r\n' java.sql.SQLException: Could not retrieve transation read-only status server at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:964) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:897) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:886) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:860) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:877) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:873) at com.mysql.jdbc.ConnectionImpl.isReadOnly(ConnectionImpl.java:3603) at com.mysql.jdbc.ConnectionImpl.isReadOnly(ConnectionImpl.java:3572) at com.mysql.jdbc.StatementImpl.executeInternal(StatementImpl.java:759) at com.mysql.jdbc.StatementImpl.execute(StatementImpl.java:739) at LoadDateFile.main(LoadDateFile.java:45) Caused by: java.sql.SQLException: Unknown system variable 'tx_read_only' at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:964) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3970) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3906) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2524) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2677) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2545) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2503) at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1369) at com.mysql.jdbc.ConnectionImpl.isReadOnly(ConnectionImpl.java:3597) ... 4 more public static void main(String[] args) { try { //System.out.println("start;"); Class.forName("com.mysql.jdbc.Driver"); //System.out.println("com.mysql;"); conn = DriverManager.getConnection(url,user,password); System.out.println("conn:"); stmt = conn.createStatement(); // System.out.println("load date infile"); String sql = "LOAD DATA INFILE '/txt/test.txt' INTO TABLE test LINES TERMINATED BY '\\r\\n' "; //sql="SELECT * FROM test"; // sql = "load data infile 'E:/mysqlsql/test.txt' replace into table test character set GBK fields terminated by ',' enclosed by '\'' lines terminated by '\r\n'"; System.out.println(sql); boolean result = stmt.execute(sql); System.out.println("Load执行结果:" + result); }catch(Exception e){ e.printStackTrace(); } }

JDBC工具类连接时的问题

在我使用JDBC连接数据库的时候总是报NoClassDefFoundError错误,我在经过多次百度无果后。决定向各位大佬请教一下。 * 错误的具体原因为: Exception in thread "main" java.lang.NoClassDefFoundError: Could not initialize class cn.itcast.jdbc.JDBCUtils # JDBCDome /** *通过键盘录入用户和密码 * 判断用户是否登录成功 */ public class jdbcDemo9 { public static void main(String[] args) { //1.键盘录入,接受用户名和密码 Scanner sc = new Scanner(System.in); System.out.println("请输入用户名"); String username = sc.nextLine(); System.out.println("请输入密码"); String password = sc.nextLine(); //2.调用方法 boolean flag = new jdbcDemo9().login(username,password); //3.判断结果输出不同语句 if (flag){ System.out.println("登录成功"); }else { System.out.println("用户名或密码错误"); } } /** * 登录方法 */ public boolean login(String username,String password){ if (username==null || password==null){ return false; } Connection conn = null; Statement stmt = null; ResultSet rs =null; //连接数据库判断是否登录成功 try { conn = JDBCUtils.getConnection();//在这里debug的时候显示conn=null //2定义sql String sql = "select * from user where username = '"+username+"' and password = '"+password+"'"; //3获取执行sql的对象 stmt = conn.createStatement(); //4执行查询 rs = stmt.executeQuery(sql); //5.判断 return rs.next(); //如果有下一行,返回true } catch (SQLException e) { e.printStackTrace(); } finally { JDBCUtils.close(rs,stmt,conn); } return false; } } ## JDBCUtils ``` /** * JDBC工具类 */ //工具类的方法应该都是静态的,这样方便我们去调用 public class JDBCUtils { private static String url; private static String user ; private static String password; private static String driver; /** * 文件的读取,只需要读取一次就可以拿到值:使用静态代码块 */ static { //获取资源文件,获取值 try { //1、Propertits集合类 Properties pro = new Properties(); //获取src路径下的文件的方式:ClassLoader 类加载器 ,要获取Classlodar,要获取他对应的字节码文件 ClassLoader classLoader = JDBCUtils.class.getClassLoader(); URL resource = classLoader.getResource("jdbc.propertits"); String path = resource.getPath(); //返回字符串路径 //System.out.println(path); //2加载文件 pro.load(new FileReader(path)); //3获取属性,赋值 url = pro.getProperty("url"); user = pro.getProperty("user"); password = pro.getProperty("password"); driver = pro.getProperty("driver"); //注册驱动 Class.forName(driver); //之前写的是:com.mysql.cj.jdbc.Driver } catch (IOException e) { e.printStackTrace(); } catch (ClassNotFoundException e) { e.printStackTrace(); } } /** * 获取连接 * @return 连接对象释放资源 */ public static Connection getConnection() throws SQLException { return DriverManager.getConnection(url,user,password); } /** * 释放资源 * @param stmt * @param conn */ public static void close(ResultSet rs,Statement stmt, Connection conn){ if (rs!=null){ try { rs.close(); } catch (SQLException e) { e.printStackTrace(); } } if (stmt!=null){ try { stmt.close(); } catch (SQLException e) { e.printStackTrace(); } } if (conn!=null){ try { conn.close(); } catch (SQLException e) { e.printStackTrace(); } } } } ``` # 配置文件 url=jdbc:mysql://localhost:3306/db4?useSSL=false&serverTimezone=UTC user=root password=nana980801 driver=com.mysql.cj.jdbc.Driver ``` ```

部署在Tomcat下,启动Tomcat时报错,试了好多办法都没用,哪位大神来解答一下,急!!!

严重: Exception sending context initialized event to listener instance of class com.hc.ems.util.EMSContextLoaderListener org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [conf/spring-config.xml]: Invocation of init method failed; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up. at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1566) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:762) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480) at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106) at com.hc.ems.util.EMSContextLoaderListener.contextInitialized(EMSContextLoaderListener.java:36) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5003) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5517) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:652) at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1263) at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1978) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) at java.util.concurrent.FutureTask.run(FutureTask.java:262) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:377) at com.mysql.jdbc.Util.getInstance(Util.java:360) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:935) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:924) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:870) at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2144) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2069) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:790) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:377) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:395) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:325) at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:148) at com.alibaba.druid.filter.stat.StatFilter.connection_connect(StatFilter.java:211) at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:142) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1377) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1431) at com.alibaba.druid.pool.DruidDataSource.init(DruidDataSource.java:632) 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.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeCustomInitMethod(AbstractAutowireCapableBeanFactory.java:1694) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1633) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1562) ... 26 more Caused by: java.sql.SQLException: null, message from server: "Host '218.29.69.90' is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'" at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:996) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:935) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:924) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1037) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2234) at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2085) ... 49 more

myeclipse与mysql连接运行servlet出问题

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Cannot load connection class because of underlying exception: 'java.lang.NumberFormatException: For input string: "3306:myceshi" myceshi是数据库名

JDBC连接不到Mysql数据库

org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. 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