2016-11-18 04:41:35.492  WARN 4256 --- [  restartedMain] o.a.tomcat.jdbc.pool.PooledConnection    : Not loading a JDBC driver as driverClassName property is null.
2016-11-18 04:41:35.499 ERROR 4256 --- [  restartedMain] o.a.tomcat.jdbc.pool.ConnectionPool      : Unable to create initial connections of pool.

java.sql.SQLException: The url cannot be null
    at java.sql.DriverManager.getConnection(DriverManager.java:649) ~[na:1.8.0_111]
    at java.sql.DriverManager.getConnection(DriverManager.java:208) ~[na:1.8.0_111]
    at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:308) ~[tomcat-jdbc-8.5.4.jar:na]
    at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:203) ~[tomcat-jdbc-8.5.4.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:716) [tomcat-jdbc-8.5.4.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:648) [tomcat-jdbc-8.5.4.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:468) [tomcat-jdbc-8.5.4.jar:na]
    at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:143) [tomcat-jdbc-8.5.4.jar:na]
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:118) [tomcat-jdbc-8.5.4.jar:na]
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:107) [tomcat-jdbc-8.5.4.jar:na]

spring.datasource.url=jdbc:oracle:thin:@localhost:1521:spring

<dependency>
    <groupId>com.oracle</groupId>
    <artifactId>ojdbc14</artifactId>
    <version>10.2.0.4.0</version>
</dependency>