1.检查Tomcat/lib下是否有mysql-connector-java.jar驱动包 2.检查jdk/jre/lib/ext 下是否有mysql-connector-java.jar驱动包 3.检查配置url的格式是否有问题 url=jdbc:mysql://localhost:3306/forum?useUnicode=true&characterEncoding=utf-8&useSSL=false