- 博客(663)
- 问答 (3)
- 收藏
- 关注
原创 什么是缓存、为什么要用缓存、缓存分类、缓存&测试、缓存更新、缓存设计考虑点、缓存测试点
什么是缓存、为什么要用缓存、缓存分类、缓存&测试、缓存更新、缓存设计考虑点、缓存测试点
2024-01-01 20:12:21
2344
翻译 启发式测试模型
The Heuristic Test Strategy Model is a set of patterns for designing and choosing tests to perform. Theimmediate purpose of this model is to remind testers of what to think about during that process. I encouragetesters to customize it to fit their own or
2021-02-19 21:08:11
1021
原创 B端与C端产品区别
目录一、B端与C端产品特点二、B端与C端产品区别三、B端和C端业务调研的区别四、B端和C端产品运营的区别五、产品的客户与用户六、两类用户的行为动机差异,决定了产品经理关注侧重点的差异七、决策优先级的差异霸占大众视线的产品普遍都是C(Customer)端产品,例如我们熟知的千千静听、暴风影音、微信、滴滴打车、微博等等,这些APP为我们的生活增添了很多乐趣。而相较于C端产品,还有另一种产品类型,他们使用的对象人数有限,需求相对固定单一,主要服务于企业内部,我们称这类产品叫B(Bussiness)端产品:例如
2021-02-09 18:24:38
3612
原创 探索式软件测试---局部探索式测试法
测试无涯,要把要做的事情分优先级测试就是有所变,有所不变可供选择的输入太多,组合太多,应该怎么办?必须在测试时确定所有可能发生变化的因素,在要求我们选择某些变量和去掉其他(也就是不必要的)变量时,我们 必须做出明智的决定。从而测试工作简化为在所有输入的全体集合中选择一个子集,然后在输入时使用选中的子集,最后通过推理认为是否这些输入就足够了。用户输入输入是由应用程序外部引发的,并导致应用程序执行了某些代码。输入分类:原子输入抽象输入:将相互关联的原子输入合并成一个抽象输入,也把原子们当成一
2021-01-31 19:43:57
560
原创 (三)箭头函数
目录一、基本用法二、基本用法举例一、基本用法(param1, param2, …, paramN) => { statements }(param1, param2, …, paramN) => expression//相当于:(param1, param2, …, paramN) =>{ return expression; }// 当只有一个参数时,圆括号是可选的:(singleParam) => { statements }singleParam => {
2021-01-24 17:24:54
217
原创 (二)高阶函数map、reduce、filter、sort、foreach
目录一、函数二、高阶函数(Higher-order function)三、map3.1语法3.2实例四、reduce4.1语法4.2举例 (无initialValue)4.2举例 (有initialValue)五、filter5.1语法5.2 举例六、sort一、函数在JavaScript中,若函数有return返回值,则将结果返回;若函数没有return,执行完函数也会有返回结果,只是结果为undefined。由于JavaScript的函数也是一个对象,上述定义的abs()函数实际上是一个函数对象,
2021-01-24 15:53:35
335
原创 (一)解构赋值
目录一、解构数组二、解构对象三、解构嵌套对象和数组从ES6开始,JavaScript可以将属性/值从对象/数组中取出,同时赋给其他变量一、解构数组传统方式:把一个数组的元素分别赋值给几个变量 let array = ['hello', 'JavaScript', 'ES6']; let x = array[0]; let y = array[1]; let z = array[2]; console.log(x+"----"+y+"----"+z)//简单数组let [x,
2021-01-24 12:12:59
186
原创 JavaScript与DOM关系、JavaScript+DOM能做什么
JavaScript与DOM关系、JavaScript+DOM能做什么、JavaScript+DOM举例
2020-05-10 20:58:14
467
原创 MySQL InnoDB MVCC实现
1.MVCC概述 2.快照读和当前读 3. undo log 4.记录中隐藏参数 5.read view6.可见性比较算法
2020-04-28 23:21:28
364
原创 record lock、gap lock、next-key lock 和事务隔离级别例子
record lock、gap lock、next-key lock 和事务隔离级别例子
2020-04-24 23:42:29
647
原创 慢索引及解决方法
An index lookup requires three steps:(1) the tree traversal;(2) following the leaf node chain;(3) fetching the table data.The tree traversal is the only step that has an upper bound for the number...
2020-04-22 00:54:10
932
原创 访问硬盘数据库过程、建立索引的好处
一、硬盘结构及工作过程磁头(head):从上到下从0开始编号 磁道(track):同心圆,编号从外向内由0开始编号 柱面(Cylinder):所有盘面的同一编号在几何上构成一个圆柱 扇区(sector):每个磁道被划分成N个弧段,每个磁道的扇区从1开始按顺序编号。对于单个扇区,也是块存储空间。常见的存储空间大小为512Byte,目前已有4k。数据存储在扇区中,磁头、磁道、柱面等让...
2020-04-20 20:12:07
616
原创 throw、throws、rethrow自定义异常类
一、throw、throws 二、re-throw 三、Difference between throw and throws 四、自定义异常类
2020-04-20 20:06:34
778
原创 try-catch-finally组合情况、执行过程字节码解读
1.try-catch-finally组合情况 2.执行过程字节码解读 3.finally中对返回值进行修改 4.finally中有返回值 5.finally是否必须执行
2020-04-20 20:02:26
525
原创 InnoDB 索引页物理结构和逻辑结构
一、物理结构 1.The FIL header and trailer 2.System records 3.User records 4.The INDEX header 二、Data Removal 三、逻辑结构 1.Leaf and non-leaf pages 2. 2.Pages at the same level 3.Innodb为主键创建索引,是强制的 4.为什么默认主键值自增的
2020-04-20 18:32:15
841
原创 Exception处理机制、Exception Handler三种方法
Throwable、Exception、ErrorThe Throwable class is the superclass of all errors and exceptions in the Java language.An Error is a subclass of Throwable that indicates serious problems that a reasonab...
2020-04-16 11:20:59
5386
原创 引用传递、值传递、Shallow Copy & Deep Copy
引用传递、值传递、Shallow Copy & Deep Copy(用构造器、或Cloneable接口实现)
2020-04-15 13:45:05
332
原创 java序列化、反序列化、serialVersionUID
java序列化概述、序列化原因、如何序列化、明确serialVersionUID的必要性、继承关系中序列化表现
2020-04-14 20:12:14
652
原创 Java IO Stream概述
一、What are the StreamsIn computer science Streams are defined as the ordered sequence of data elements.Provides a common I/O modelAbstract details of underlying source or destinationStream type...
2020-04-14 13:24:33
434
原创 Reader、Writer、BufferedWriter源码解析
Reader(read方法)、Writer(write、flush源码解析)、BufferedWriter源码解析
2020-04-13 19:05:57
376
原创 InputStream、OutputStream、BufferedOutputStream源码解析
InputStream(read方法)、OutputStream(write方法)BufferedOutputStream源码解析
2020-04-12 23:35:05
414
原创 泛型Generics
generics、generic type、Generic Method、Bounded Type Parameters、Wildcards、API应用举例
2020-04-09 20:41:10
337
原创 HashMap、Hashtable、LinkedHashMap、TreeMap 数据结构及不同点
HashMap(数组链表hashcode_equal)、Hashtable、LinkedHashMap(doubly-linked list)、TreeMap(红黑树) 数据结构及不同点
2020-04-07 21:51:22
355
原创 ArrayList、LinkedList、Vector
ArrayList(Size And Capacity数据结构、add、remove)、LinkedList(数据结构、add、remove)、Vector
2020-04-04 19:38:24
188
原创 String、StringBuffer、StringBuilder
String(两种创建对象方式及在堆栈中存储、immutable、字符串拼接执行优化)、StringBuffer、StringBuilder
2020-04-03 18:40:01
283
原创 Java Inner Class
Nested ClassesThe Java programming language allows you to define a class within another class. Such a class is called a nested class, and the class that holds the inner class is called the outer clas...
2020-04-02 00:15:57
314
翻译 Non-blocking Algorithms
Non-blocking algorithms in the context of concurrency are algorithms that allows threads to access shared state (or otherwise collaborate or communicate) without blocking the threads involved. In more...
2020-03-30 16:42:34
455
翻译 Compare and Swap 、Anatomy of a Synchronizer
一、Compare and SwapCompare and swap is a technique used when designing concurrent algorithms. Basically, compare and swap compares an expected value to the concrete value of a variable, and if the con...
2020-03-25 21:33:31
235
翻译 Blocking Queues
A blocking queue is a queue that blocks when you try to dequeue from it and the queue is empty, or if you try to enqueue items to it and the queue is already full. A thread trying to dequeue from an e...
2020-03-25 15:06:53
232
翻译 Thread Pools
Thread PoolsThread Pools are useful when you need to limit the number of threads running in your application at the same time. There is a performance overhead associated with starting a new thread, a...
2020-03-25 14:41:02
2207
翻译 Semaphores
A Semaphore is a thread synchronization construct that can be used either to send signals between threads to avoid missed signals, or to guard a critical section like you would with a lock. Java 5 com...
2020-03-25 13:21:11
350
翻译 Read / Write Locks in Java(未完)
A read / write lock is more sophisticated lock than the Lock implementations shown in the text Locks in Java. Imagine you have an application that reads and writes some resource, but writing it is not...
2020-03-24 22:41:57
228
翻译 Slipped Conditions
What is Slipped Conditions?Slipped conditions means, that from the time a thread has checked a certain condition until it acts upon it, the condition has been changed by another thread so that it is ...
2020-03-24 17:34:56
229
1
翻译 Nested Monitor Lockout嵌套的监控程序锁死
How Nested Monitor Lockout OccursNested monitor lockout is a problem similar to deadlock. A nested monitor lockout occurs like this:嵌套监视器锁定是一个类似于死锁的问题。 发生嵌套监视器锁定,如下所示:Thread 1 synchronizes on AThr...
2020-03-23 19:32:29
320
翻译 Lock
A lock is a thread synchronization mechanism like synchronized blocks except locks can be more sophisticated than Java’s synchronized blocks. Locks (and other more advanced synchronization mechanisms)...
2020-03-23 16:58:06
331
翻译 Starvation and Fairness
If a thread is not granted CPU time because other threads grab it all, it is called “starvation”. The thread is “starved to death” because other threads are allowed the CPU time instead of it. The sol...
2020-03-23 14:45:31
399
空空如也
java接口初始化为什么生成clinit方法
2020-03-04
hadoop初学者,集群建立成功,执行圆周率例子,出现如下错误,请大神们帮忙看下
2018-11-25
TCP网络编程:服务器端的while为什么不能循环结束
2017-07-29
TA创建的收藏夹 TA关注的收藏夹
TA关注的人