ERROR DruidDataSource.run - create connection error, url: XXX，errorCode 17002, state null

异常信息为：

2018-11-08 10:25:45.656 [Druid-ConnectionPool-Create-1885606918] ERROR DruidDataSource.run - create connection error, url: jdbc:oracle:thin:XXX:orcl, errorCode 17002, state null
java.sql.SQLException: Io 异常: The Network Adapter could not establish the connection
	at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:113) ~[ojdbc14-10.2.0.5.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
	at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:147) ~[ojdbc14-10.2.0.5.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
	at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:257) ~[ojdbc14-10.2.0.5.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
	at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:389) ~[ojdbc14-10.2.0.5.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
	at oracle.jdbc.driver.PhysicalConnection.(PhysicalConnection.java:454) ~[ojdbc14-10.2.0.5.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
	at oracle.jdbc.driver.T4CConnection.(T4CConnection.java:165) ~[ojdbc14-10.2.0.5.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
	at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:35) ~[ojdbc14-10.2.0.5.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
	at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:802) ~[ojdbc14-10.2.0.5.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
	at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1464) ~[druid-1.1.4.jar:1.1.4]
	at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1529) ~[druid-1.1.4.jar:1.1.4]
	at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2277) ~[druid-1.1.4.jar:1.1.4]

主要检查：

1.是否存在网络波动；

2.数据库地址配置是否正确；

3.数据库服务是否正常启动；