com.alibaba.druid.pool.DruidDataSource : {dataSource-1} init error和SQL NullPointException

文章借鉴：com.alibaba.druid.pool.DruidDataSource : {dataSource-2} init error

2019-03-26 22:37:31.021 ERROR 13308 --- [ main] com.alibaba.druid.pool.DruidDataSource   : {dataSource-1} init errorjava.lang.NullPointerException: null
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:325) ~[na:1.8.0_181]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[na:1.8.0_181]
    at com.alibaba.druid.util.JdbcUtils.createDriver(JdbcUtils.java:581) ~[druid-1.1.6.jar:1.1.6]
    at com.alibaba.druid.pool.DruidDataSource.init(DruidDataSource.java:815) [druid-1.1.6.jar:1.1.6]
    at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1221) [druid-1.1.6.jar:1.1.6]
    at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1217) [druid-1.1.6.jar:1.1.6]
    at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:90) [druid-1.1.6.jar:1.1.6]
    at org.springframework.jdbc.datasource.DataSourceUtils.fetchConnection(DataSourceUtils.java:157) [spring-jdbc-5.1.5.RELEASE.jar:5.1.5.RELEASE]
    at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:115) [spring-jdbc-5.1.5.RELEASE.jar:5.1.5.RELEASE]
    at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:78) [spring-jdbc-5.1.5.RELEASE.jar:5.1.5.RELEASE]
    at org.mybatis.spring.transaction.SpringManagedTransaction.openConnection(SpringManagedTransaction.java:82) [mybatis-spring-1.3.2.jar:1.3.2]
    at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:68) [mybatis-spring-1.3.2.jar:1.3.2]
    at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:338) [mybatis-3.4.6.jar:3.4.6]
    at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:84) [mybatis-3.4.6.jar:3.4.6]
    at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:62) [mybatis-3.4.6.jar:3.4.6]
    at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:326) [mybatis-3.4.6.jar:3.4.6]
    at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156) [mybatis-3.4.6.jar:3.4.6]
    at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109) [mybatis-3.4.6.jar:3.4.6]
    at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:83) [mybatis-3.4.6.jar:3.4.6]
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) [mybatis-3.4.6.jar:3.4.6]
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) [mybatis-3.4.6.jar:3.4.6]
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:77) [mybatis-3.4.6.jar:3.4.6]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_181]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_181]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_181]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_181]
    at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:433) [mybatis-spring-1.3.2.jar:1.3.2]
    at com.sun.proxy.$Proxy67.selectOne(Unknown Source) [na:na]
    at org.mybatis.spring.SqlSessionTemplate.selectOne(SqlSessionTemplate.java:166) [mybatis-spring-1.3.2.jar:1.3.2]
    at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:83) [mybatis-3.4.6.jar:3.4.6]
    at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:59) [mybatis-3.4.6.jar:3.4.6]
    at com.sun.proxy.$Proxy82.selectByPrimaryKey(Unknown Source) [na:na]
    at com.leyou.mapper.UserMapperTest.testQuer(UserMapperTest.java:24) [test-classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_181]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_181]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_181]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_181]
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50) [junit-4.12.jar:4.12]
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) [junit-4.12.jar:4.12]
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47) [junit-4.12.jar:4.12]
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) [junit-4.12.jar:4.12]
    at 

org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.NullPointerException
### The error may exist in com/leyou/mapper/UserMapper.java (best guess)
### The error may involve com.leyou.mapper.UserMapper.selectByPrimaryKey
### The error occurred while executing a query
### Cause: java.lang.NullPointerException

    at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:77)
    at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:446)
    at com.sun.proxy.$Proxy67.selectOne(Unknown Source)
    at org.mybatis.spring.SqlSessionTemplate.selectOne(SqlSessionTemplate.java:166)
    at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:83)
    at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:59)
    at com.sun.proxy.$Proxy82.selectByPrimaryKey(Unknown Source)
    at com.leyou.mapper.UserMapperTest.testQuer(UserMapperTest.java:24)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)

好了，报错如上，我们知道了错误是这样的，我在刚看到这个错误地时候，就被java.lang.NullPointerException: null给吸引了，觉得不可能呀，哪里为null了。。。就直接去百度了，结果当然是没结果了。。

继续往下看，然后又被吸引了。。。

org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.NullPointerException
### The error may exist in com/leyou/mapper/UserMapper.java (best guess)
### The error may involve com.leyou.mapper.UserMapper.selectByPrimaryKey
### The error occurred while executing a query
### Cause: java.lang.NullPointerException

这个错误让我坚定的认为我哪里写错了，就理解了第一句：查询数据库出错，空指针异常！

对于查询数据库空指针的问题，又去百度了一通，没找到原因。

好了，绝望的时候总是会出现奇迹的。。。

com.alibaba.druid.pool.DruidDataSource   : {dataSource-1} init error

第一行的报错终于引起了我这个沙雕的注意！

再去百度，说我的数据库配置的有问题：

我没有排查，直接找了一个正确的配置信息复制黏贴过来就用了，然后就没事了

jdbc.driverClassName=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/javaee?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone = GMT
jdbc.username=root
jdbc.password=root
logging.level.com.example.demo=debug
server.port=8088
server.servlet.context-path=/
mybatis.type-aliases-package=com.leyou.pojo

很懵？我真的很懵。。。