JAVA intermediate and senior interview summary

1. Basic knowledge of Java

1. Understanding of Java's object-oriented thinking

    The understanding of Java object-oriented thinking is mainly to examine the characteristics of object-oriented, mainly polymorphism.

    https://blog.csdn.net/dgxin_605/article/details/80201721

2. Collection framework: ArrayList, LinkedList, HashMap, LinkedHashMap, ConcurrentHashMap, HashTable, HashSet's underlying source code implementation principle

   https://blog.csdn.net/dgxin_605/article/details/80201817