摘要： cankao : https://www.jianshu.com/p/6ee7e4cd5314 Collectors.toMap Collectors.partitioningBy Collectors.groupingBy 1.Collectors.toMap: Student studentA 阅读全文

摘要： 参考:https://www.jianshu.com/p/154c82073b07 依赖: <dependency> <groupId>net.sf.ehcache</groupId> <artifactId>ehcache</artifactId> <version>2.10.2</version 阅读全文