Interview Topics:

1-10 questions:

The difference between equals and hashCode in Java

2, the difference between int and integer

3, String, StringBuffer, StringBuilder

What is an inner class? The role of inner classes

5. The difference between processes and threads

6. Final, finally, Finalize

7, Serializable and Parcelable difference

Can static properties and methods be inherited? Can it be rewritten? And why?

Member inner classes, static inner classes, local inner classes and anonymous inner classes, and their application in projects

10. How to convert string into INTEGER

11-20 questions:

11. Under what circumstances are objects disposed of by the garbage collection mechanism?

12. What is the difference between static proxy and dynamic proxy?

14. What is the mechanism for implementing polymorphism in Java?

16. Tell me what you understand about Java reflection

17. Tell me what you understand about Java annotations

18, Java String understanding

19. Why is String made immutable?

Object equal and hashCode methods overwrited. why? ,

Questions 21 to 40

21, List,Set,Map

26. ArrayMap vs. HashMap

29, The difference between HashMap and HashTable

30. Differences between HashMap and HashSet

31 to 40 items

31, How to determine whether a HashSet element is identical to a HashMap element?

33. Differences between ArrayList and LinkedList, and application scenarios

34. The difference between arrays and lists

35, Three ways to start a thread?

The difference between a thread and a process?

38, The run() and start() methods are different

39. How do I control the number of concurrent access threads a method allows?

40. Differences between Wait and SEELp in Java

41 to 50

41, Talk about wait/notify

42. What causes a thread to block? How do threads close?

How to ensure thread safety?

44, How to implement thread synchronization?

45, Interthread operation List

Talk about the understanding of Synchronized keyword, class lock, method lock, reentrant lock

The difference between synchronized and volatile

51-58

51. ReentrantLock, synchronized, and volatile

The four necessary conditions for deadlock?

56, What is a thread pool and how to use it?

56, What is a thread pool and how to use it?

58, There are three threads T1, T2, T3, how to ensure that they are executed in order?

Interview answer:

Being able to answer questions is only the first step in an interview with a good company. The more you can answer questions, the more they will ask questions. I want readers to know what it means to go deeper. It’s really a process.

How well you prepare for your knowledge directly determines whether you can successfully pass the first and second interviews. Therefore, it is necessary to comb your knowledge before the interview to see whether you need to improve your knowledge reserve.

As for knowledge sorting, here is my review route during the interview :(the following systematic review materials are collected and sorted by me from various leaders)

  • Basic skills for architect: Deep Java generics + annotations + simple + concurrent programming + data transfer and serialization +Java Virtual Machine principles + reflection and class loading + dynamic proxy + efficient IO

  • Android advanced UI and FrameWork source code: advanced UI promotion + FrameWork kernel parsing +Android component kernel data persistence

  • 360° all-round performance tuning: design philosophy and code quality optimization + program performance optimization + development efficiency optimization

  • Interpretation of open source framework design ideas: hot repair design + plug-in framework interpretation + component framework design + picture loading framework + network access framework design +RXJava responsive programming framework design +IOC architecture design +Android architecture component Jetpack

  • NDK module development: NDK basic knowledge system + bottom image processing + audio and video development

  • Wechat small program: small program introduction +UI development +API operation + wechat docking

  • Hybrid Development and Flutter: Html5 project Combat +Flutter advanced

After the knowledge is sorted out, it is necessary to check and fill in the gaps. Therefore, I have prepared many e-books and notes for these knowledge points, which make a perfect summary of each knowledge point.

Android Development Interview Guide: 379 pages

Including Tencent, Baidu, Xiaomi, Ali, LeEco, Meituan, 58, Cheetah, 360, Sina, Sohu and other first-line Internet companies interview questions were asked. Familiarity with the points listed in this article will greatly increase your chances of passing the first two rounds of technical interviews.

507 pages of Android Development related source code analysis

As long as programmers, whether Java or Android, if not to read the source code, only to see API documents, it is just stay in the skin, which is detrimental to the establishment and completion of our knowledge system and the promotion of actual combat technology.

The real best exercise is to read the source code directly, not only limited to reading the major system source code, but also including all kinds of excellent open source libraries.

The above resources are free to share, the above content in the open source project: [Github] has been included, you can get their own.