# Android_QA

**Repository Path**: lengyueming/Android_QA

## Basic Information

- **Project Name**: Android_QA
- **Description**: Android 面试、笔试题集锦（赋答案，持续更新 ing~）
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 2
- **Created**: 2021-01-15
- **Last Updated**: 2021-04-05

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# Android_QA

2020 年 10 月 27 重磅更新：

最真实的 Android 面经，最详细的面试回答，我都给你准备好啦！

几大公司面试问题：[https://juejin.im/post/6878902981400625160](https://juejin.im/post/6878902981400625160) 里面都备注了**回答要点**！

最重要的，遇到这些面试题**该如何回答**我都给你写好了，我愿称之为最强口水话。

✨✨✨ Android 面试必备 --- 口水话系列 ✨✨✨

> 何为口水话呢？
>
> 就是面试官问你相关问题的时候，你应该如何说的话。
>
> 有没有遇到这样的场景，明明面试官问我的问题我会，我也看过甚至我自己也写过相关博客，但是在回答的时候还是支支吾吾说不清楚，或者不分轻重想到啥就说啥。
>
> 口水话专门用来解决这个问题，它不同于一般博客语言琐碎，而是语言精炼，突出重点，以沟通的方式而非说教的形式去阐述问题。

详细见：[https://github.com/Omooo/Android-Notes](https://github.com/Omooo/Android-Notes)

**这一次，轻松拿下 Android 面试！**

## Java 部分（一）基础知识点

1. [Java中 == 和 equals 和 hashCode 的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_1)
2. [int、char、long 各占多少字节数](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_2)
3. [int 和 Integer 的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_3)
4. [谈谈对Java多态的理解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_4)
5. [String、StringBuffer、StringBuilder的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_5)
6. [什么是内部类？内部类的作用](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_6)
7. [抽象类和接口的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_7)
8. [抽象类的意义](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_8)
9. [抽象类与接口的应用场景](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_9)
10. [抽象类是否可以没有方法和属性？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_10)
11. [接口的意义](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_11)
12. [泛型中的extends和super的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_12)
13. [父类的静态方法能否被子类重写？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_13)
14. [进程和线程的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_14)
15. [final、finally、finalize的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_15)
16. [序列化的方式](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_16)
17. [Serializable 和 Parcelable 的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_17)
18. [静态属性和静态方法是否可以被继承？是否可以被重写？以及原因。](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_18)
19. [静态内部类的设计意图](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_19)
20. [成员内部类、静态内部类、方法内部类（局部内部类）和匿名内部类的理解，以及项目中的应用](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_20)
21. [谈谈对kotlin的理解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_21)
22. [闭包和局部内部类的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_22)
23. [String转换成Integer的方式以及原理](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_23)
24. [面向对象思想](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_24)
25. [对象拷贝的理解？深拷贝、浅拷贝的区别？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_25)
26. [Enumeration 和 Iterator 的区别？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_base_26)
27. 



## Java 部分（二）高级知识点

1. [哪些情况下的对象会被垃圾回收机制处理掉？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_1)
2. [讲一下常见的编码方式？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_2)
3. [UTF-8编码中中文占几个字节，int型几个字节？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_3)
4. [静态代理和动态代理的区别，什么场景使用？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_4)
5. [Java的异常体系](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_5)
6. [谈谈你对解析与分派的认识](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_6)
7. [修改对象A的equals方法的签名，那么使用HashMap存放这个对象实例的时候，会调用哪个equals方法？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_7)
8. [Java中实现多态的机制是什么？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_8)
9. [如何将一个Java对象序列化到文件里？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_9)
10. [说说你对Java反射的理解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_10)
11. [说说你对Java注解的理解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_11)
12. [说说你对依赖注入的理解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_12)
13. [说一下泛型原理，并举例说明](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_13)
14. [ Java中String的了解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_14)
15. [String为什么要设计成不可变的？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_15)
16. [Object类的equal和hashCode方法重写，为什么？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_16)
17. [为什么Java里的匿名内部类只能访问final修饰的外部变量？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_17)
18. [Synchronized](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_18)
19. [volatile](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_19)
20. [类加载流程双亲委托机制](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_advance_20)



## Java 部分（三）数据结构

1. [常用数据结构简介](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_structure_1)
2. [并发集合了解哪些？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_structure_2)
3. [HashMap](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_structure_3)



## Java 部分（四）线程、多线程和线程池

1. [开启线程的三种方式？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_1)
2. [线程和进程的区别？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_2)
3. [为什么要有线程，而不是仅仅用进程？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_3)
4. [run() 和 start() 方法的区别？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_4)
5. [如何控制某个方法允许并发访问线程的个数？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_5)
6. [在 Java 中 wait() 和 sleep() 方法的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_6)
7. [谈谈 wait/notify 关键字的理解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_7)
8. [什么导致线程阻塞？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_8)
9. [线程如何关闭？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_9)
10. [讲一下 Java 中的同步的方法](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_10)
11. [数据一致性如何保证？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_11)
12. [如何保证线程安全？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_12)
13. [如何实现线程同步？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_13)
14. [两个进程同时要求读写，能不能实现？如何防止进程同步？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_14)
15. [线程间操作 List](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_15)
16. [Java 中对象的生命周期](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_16)
17. [说说线程池](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_17)
18. [并发编程面临的挑战有哪些？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#java_thread_18)
19. 



## Android 部分（一）基础知识点

1. [四大组件是什么？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_1)
2. [四大组件的生命周期和简单用法](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_2)
3. [Context的理解？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_3)
4. [AsyncTask详解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_4)
5. [Android虚拟机以及编译过程](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_5)
6. [进程保活方案](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_6)
7. [Android 消息机制](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_7)
8. [Window、Activity、DecorView以及ViewRoot之间的关系](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_8)
9. [Android事件分发机制](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_9)
10. [dp、sp、px的理解以及相互转换](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_10)
11. [RelativeLayout和LinearLayout在实现效果同等的情况下使用哪个？为什么？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_11)
12. [布局相关的 \<merge>、\<viewstub> 控件作用及实现原理](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_12)
13. [Fragment详解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_13)
14. [Json、XML](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_14)
15. [Assets目录与res目录的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_15)
16. [View视图绘制过程原理](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_16)
17. [解决滑动冲突的方式？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_17)
18. [APP Build过程](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_18)
19. [Android利用scheme协议进行跳转](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_19)
20. [MVC、MVP](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_20)
21. [SurfaceView](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_21)
22. [HandlerThread](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_22)
23. [IntentService](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_23)
24. [谈谈你对Application类的理解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_24)
25. [Android为什么要设计出Bundle而不是直接使用HashMap来进行数据传递？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_25)
26. [SharedPreference在使用过程中有什么注意点？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_26)
27. [SQLite有哪些可以优化的地方？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_27)
28. [嵌滑滑动机制](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_28)
29. [RecyclerView 优化](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_base_29)



## Android 部分（二）高级知识点

1. [Android 系统架构](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_1)
2. [Android 各个版本特性](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_2)
3. [Android 系统启动流程](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_3)
4. [应用程序进程启动过程](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_4)
5. [Activity 状态的保存与恢复](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_5)
6. [Android 动画框架实现原理](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_6)
7. [requestLayout、onLayout、onDraw、drawChild 区别与联系](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_7)
8. [requestLayout、invalidate、postInvalidate 的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_8)
9. [Activity、Window、View 的区别及联系](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_9)
10. [Volley 的理解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_10)
11. [如何优化自定义 View](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_11)
12. [低版本如何实现高版本 API](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_12)
13. [描述一次网络请求的过程](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_13)
14. [HttpUrlConnection 与 OkHttp 的关系](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_14)
15. [Bitmap 的理解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_15)
16. [Looper 架构](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_16)
17. [ActivityThread 的工作原理](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_17)
18. [AMS 的工作原理](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_18)
19. [WMS 的工作原理](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_19)
20. [自定义 View 如何考虑机型适配](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_20)
21. [自定义 View 的事件](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_21)
22. [LaunchMode 应用场景](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_22)
23. [SpareArray 原理](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_23)
24. [ContentProvider 是如何实现数据共享的](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_24)
25. [Service 与 Activity 的通信方式](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_25)
26. [IntentService 原理与作用](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_26)
27. [ApplicationContext 与 ActivityContext 的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_27)
28. [SP 是进程同步的嘛？如何做到进程同步？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_28)
29. [谈谈多线程在 Android 中的使用](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_29)
30. [进程和 Application 的生命周期](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_30)
31. [封装 View 时候这么知道 View 的大小？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_31)
32. [RecycleView 原理](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_32)
33. [AndroidManifest 的作用和理解](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_33)
34. [Touch 事件流程](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_34)
35. [时间分发中的 onTouch 和 onTouchEvent 有什么区别？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_35)
36. [View 和 ViewGroup 分别有哪些与事件分发有关的回掉方法](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_36)
37. [View 的刷新机制](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_37)
38. [View 的绘制流程](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_38)
39. [自定义控件原理？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_39)
40. [为什么不能在子线程更新 UI？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_40)
41. [ANR 产生原因是什么？如何定位和修正？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_41)
42. [什么情况下会导致 OOM，如何避免？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_42)
43. [OOM 是否可以 try-catch](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_43)
44. [内存泄露发生的情况？如何避免](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_44)
45. [LruCache 默认缓存大小？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_45)
46. [ContentProvider 的权限管理](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_46)
47. [如何通过广播拦截一条短信](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_47)
48. [广播是否可以请求网络？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_48)
49. [计算一个 View 的嵌套层级？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_49)
50. [Activity 栈](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_50)
51. [Android 线程有没有限制？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_51)
52. [线程池有没有上限？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_52)
53. [有没有尝试简化 Parcelable 的使用？](https://github.com/Omooo/Android_QA/blob/master/Answer.md#android_advance_53)

## 数据结构

1. [线性表]()



## 计算机网络

1. [TCP 和 UDP 的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#net_1)
2. [Http1.1和Http1.0及2.0的区别](https://github.com/Omooo/Android_QA/blob/master/Answer.md#net_2)
3. [DNS解析过程](https://github.com/Omooo/Android_QA/blob/master/Answer.md#net_3)
4. [HTTP请求报文和响应报文](https://github.com/Omooo/Android_QA/blob/master/Answer.md#net_4)
5. [简述HTTP](https://github.com/Omooo/Android_QA/blob/master/Answer.md#net_5)
6.