mybatis下opening session时空指针异常_eatricei的博客_error opening session

先看错误信息

Exception in thread "main" org.apache.ibatis.exceptions.PersistenceException: 
### Error opening session.  Cause: java.lang.NullPointerException
### Cause: java.lang.NullPointerException
	at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:23)
	at org.apache.ibatis.session.defaults.DefaultSqlSessionFactory.openSessionFromDataSource(DefaultSqlSessionFactory.java:88)
	at org.apache.ibatis.session.defaults.DefaultSqlSessionFactory.openSession(DefaultSqlSessionFactory.java:43)
	at com.swj.util.DbUtil.openSession(DbUtil.java:30)
	at com.swj.test.Test.main(Test.java:13)
Caused by: java.lang.NullPointerException
	at org.apache.ibatis.session.defaults.DefaultSqlSessionFactory.openSessionFromDataSource(DefaultSqlSessionFactory.java:83)
	... 3 moreException in thread "main" org.apac