java -jar mybatis-generator-core-x.x.x.jar -configfile generatorConfig.xml
   java -jar mybatis-generator-core-x.x.x.jar -configfile generatorConfig.xml -overwrite
   java -cp mybatis-generator-core-x.x.x.jar org.mybatis.generator.api.ShellRunner -configfile generatorConfig.xml
   java -cp mybatis-generator-core-x.x.x.jar org.mybatis.generator.api.ShellRunner -configfile generatorConfig.xml -overwrite