作為一名Sping初學者，今天第一次配置Spring數據源就遇到好幾個坑人的地方，記錄下來做個備忘。
1.
Mon Nov 27 21:42:01 CST 2017 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification. Mon Nov 27 21:42:02 CST 2017 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification. Mon Nov 27 21:42:02 CST 2017 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification. Mon Nov 27 21:42:02 CST 2017 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification.
向數據庫發送請求后一直都在報這個，其實這個問題早在學習jdbc時就遇到了，只需要在jdbc的URL后面加上 useUnicode=true&characterEncoding=utf-8&useSSL=false 即可；
2.
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.
原來的jdbc驅動是 com.mysql.jdbc.Driver ， 改為 com.mysql.cj.jdbc.Driver 即可；
3.
1 27-Nov-2017 21:58:49.667 警告 [C3P0PooledConnectionPoolManager[identityToken->1hgefi99r1yeux661are7zk|12876430]-HelperThread-#0] com.mchange.v2.resourcepool.BasicResourcePool. com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@74bb9e1f -- 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 (10). Last acquisition attempt exception: 2 java.sql.SQLException: The server time zone value '???ú±ê×??±??' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. 3 at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:121) 4 at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) 5 at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:81) 6 at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:55) 7 at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:65) 8 at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:70) 9 at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:853) 10 at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:440) 11 at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:241) 12 at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:221) 13 at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:175) 14 at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:220) 15 at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:206) 16 at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:203) 17 at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1138) 18 at com.mchange.v2.resourcepool.BasicResourcePool.doAcquireAndDecrementPendingAcquiresWithinLockOnSuccess(BasicResourcePool.java:1125) 19 at com.mchange.v2.resourcepool.BasicResourcePool.access$700(BasicResourcePool.java:44) 20 at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1870) 21 at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:696) 22 Caused by: com.mysql.cj.core.exceptions.InvalidConnectionAttributeException: The server time zone value '???ú±ê×??±??' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. 23 at sun.reflect.GeneratedConstructorAccessor15.newInstance(Unknown Source) 24 at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) 25 at java.lang.reflect.Constructor.newInstance(Constructor.java:423) 26 at com.mysql.cj.core.exceptions.ExceptionFactory.createException(ExceptionFactory.java:54) 27 at com.mysql.cj.core.exceptions.ExceptionFactory.createException(ExceptionFactory.java:73) 28 at com.mysql.cj.core.util.TimeUtil.getCanonicalTimezone(TimeUtil.java:118) 29 at com.mysql.cj.mysqla.MysqlaSession.configureTimezone(MysqlaSession.java:360) 30 at com.mysql.cj.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:1434) 31 at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:986) 32 at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:843) 33 ... 12 more 34 35 27-Nov-2017 21:58:49.669 嚴重 [C3P0PooledConnectionPoolManager[identityToken->1hgefi99r1yeux661are7zk|12876430]-HelperThread-#0] com.mchange.v2.resourcepool.BasicResourcePool. A RESOURCE POOL IS PERMANENTLY BROKEN! [com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@74bb9e1f] (because a series of 10 acquisition attempts failed.) 36 27-Nov-2017 21:58:49.671 嚴重 [C3P0PooledConnectionPoolManager[identityToken->1hgefi99r1yeux661are7zk|12876430]-HelperThread-#0] com.mchange.v2.resourcepool.BasicResourcePool. com.mchange.v2.resourcepool.BasicResourcePool@7f3d74fe -- Unexpectedly broken!!! 37 com.mchange.v2.resourcepool.ResourcePoolException: Unexpected Break Stack Trace! 38 at com.mchange.v2.resourcepool.BasicResourcePool.unexpectedBreak(BasicResourcePool.java:974) 39 at com.mchange.v2.resourcepool.BasicResourcePool.access$1000(BasicResourcePool.java:44) 40 at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1927) 41 at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:696) 42 43 27-Nov-2017 21:58:49.678 信息 [http-nio-8080-exec-4] com.mchange.v2.resourcepool.BasicResourcePool. com.mchange.v2.resourcepool.BasicResourcePool@7f3d74fe -- an attempt to checkout a resource was interrupted, because the pool is now closed. [Thread: http-nio-8080-exec-4]
關鍵在第二行，在jdbc的url后面在加上一個 serverTimezone=UTC 就行了。
最后上一下最終修改好的數據源配置代碼
jdbc.properties
1 ###### C3P0 MySQL CONFIG ####### 2 jdbc.driverClassName=com.mysql.cj.jdbc.Driver 3 jdbc.url=jdbc:mysql://localhost/localstudent?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=UTC 4 jdbc.username=root 5 jdbc.password=123456 6 7 connection.initialPoolSize=1 8 connection.minPoolSize=1 9 connection.maxPoolSize=5 10 connection.acquireIncrement=2 11 connection.acquireRetryAttempts=10 12 connection.acquireRetryDelay=1000 13 connection.maxIdleTime=3600 14 connection.idleConnectionTestPeriod=20 15 connection.maxStatements=0 16 connection.maxStatementsPerConnection=0
springmvc-servlet.xml
1 <!-- 獲取mysql數據庫連接池配置信息 --> 2 <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> 3 <property name="locations" value="classpath:config/jdbc.properties"/> 4 </bean> 5 <!-- 配置c3p0數據源連接池 --> 6 <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" 7 destroy-method="close"> 8 <property name="driverClass" value="${jdbc.driverClassName}"/> 9 <property name="jdbcUrl" value="${jdbc.url}"/> 10 <property name="user" value="${jdbc.username}"/> 11 <property name="password" value="${jdbc.password}"/> 12 <property name="initialPoolSize" value="${connection.initialPoolSize}"/> 13 <property name="minPoolSize" value="${connection.minPoolSize}"/> 14 <property name="maxPoolSize" value="${connection.maxPoolSize}"/> 15 <property name="acquireIncrement" value="${connection.acquireIncrement}"/> 16 <property name="acquireRetryAttempts" value="${connection.acquireRetryAttempts}"/> 17 <property name="acquireRetryDelay" value="${connection.acquireRetryDelay}"/> 18 <property name="maxIdleTime" value="${connection.maxIdleTime}"/> 19 <property name="idleConnectionTestPeriod" value="${connection.idleConnectionTestPeriod}"/> 20 <property name="maxStatements" value="${connection.maxStatements}"/> 21 <property name="maxStatementsPerConnection" value="${connection.maxStatementsPerConnection}"/> 22 <property name="preferredTestQuery" value="select 1"/> 23 <property name="breakAfterAcquireFailure" value="true"/> 24 <property name="testConnectionOnCheckout" value="false"/> 25 </bean>