错误

Could not find artifact com.oracle:ojdbc6:pom:11.2.0.4 in central (https://repo.maven.apache.org/maven2)

原因

 OJDBC6的Maven代码groupId写错了，正确的如下

<!-- https://mvnrepository.com/artifact/com.oracle.database.jdbc/ojdbc6 -->
<dependency><groupId>com.oracle.database.jdbc</groupId><artifactId>ojdbc6</artifactId><version>11.2.0.4</version>
</dependency>