2011年3月7日
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摘要: 一个完整的自动化测试框架体系包含以下几个部分：1、自动化测试框架；2、测试脚本以及测试数据管理；3、测试脚本的执行管理系统；4、测试结果的显示与分析系统。其中最重要的是自动化测试框架部分。
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摘要: JUnit
JUnit是由 Erich Gamma 和 Kent Beck 编写的一个回归测试框架（regression testing framework）。Junit测试是程序员测试，即所谓白盒测试，因为程序员知道被测试的软件如何（How）完成功能和完成什么样（What）的功能。Junit是一套框架，继承TestCase类，就可以用Junit进行自动测试了。
更多JUnit信息
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摘要: Have you wondered why certain programs are located under /bin, or /sbin, or /usr/bin, or /usr/sbin?
For example, less command is located under /usr/bin directory. Why not /bin, or /sbin, or /usr/sbin? What is the different between all these directories?
In this article, let us review the Linux filesystem structures and understand the meaning of individual high-level directories
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摘要: 当今互联网的发展，已不是大鱼吃小鱼的时代，而是快鱼吃慢鱼的时代。互联网产品的制胜原则就是一个字——“快”。在各种形态的产品研发中，我们始终贯彻如一的价值观之一就是“快”，我们应该如何来理解和诠释“快”？又会从哪些方面来执行贯彻这个原则呢？
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摘要: 软件测试的十二个误区大体总结如下：
1) 测试人员不需要了解软件开发的知识：
这个很要命的，我们谈到软件测试人员未来的发展方向大致有：自动化测试，性能测试，测试管理，项目经理。这其中自动化测试和性能测试包括项目管理，都会要求对软件开发有深入的理解，如何能设计一个好的自动化框架，好的性能测试用例，如何管理一个开发团队，这都需要我们在软件开发方面有所掌握。不单要掌握，而且要精通。此其一。
其二：如果不了解开发知识，测试人员很容易被开发人员牵着鼻子走，因为开发人员随便一忽悠，你如果不了解个中奥妙，你一个字也说不上来。(以前我们讨论 Cookie和Session，由于GoAhead不支持Session，只能用Cookie来控制，差点别开发人员忽悠了)
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摘要: 写在前面：写Android程序有一个很重要的原则，不阻塞UI线程。因此Android提供了5种方法来，让一些耗时的作业在其它线程中执行，然后把结果返回给UI线程，以免阻塞UI线程。
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探讨了软件测试的可测试性，主要包括Controllability, Observability, Availability,Simplicity, Stability 和 Information.
HeuristicsOfSoftwareTestability.pdf
摘要: android的selector的用法：
首先android的selector是在drawable/xxx.xml中配置的。
先看一下listview中的状态：
把下面的XML文件保存成你自己命名的.xml文件（比如list_item_bg.xml），在系统使用时根据ListView中的列表项的状态来使用相应的背景图片。drawable/list_item_bg.xml
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摘要: The Monkey is a command-line tool that that you can run on any emulator instance or on a device. It sends a pseudo-random stream of user events into the system, which acts as a stress test on the application software you are developing.
The Monkey includes a number of options, but they break down into four primary categories:
Basic configuration options, such as setting the number of events to attempt.
Operational constraints, such as restricting the test to a single packag
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摘要: Programmers can configure logging either by creating loggers, handlers, and formatters explicitly in a main module with the configuration methods listed above (using Python code), or by creating a logging config file. The following code is an example of configuring a very simple logger, a console handler, and a simple formatter in a Python module:
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摘要: Android系统中Looper负责管理线程的消息队列和消息循环，具体实现请参考Looper的源码。 可以通过Loop.myLooper()得到当前线程的Looper对象，通过Loop.getMainLooper()可以获得当前进程的主线程的Looper对象。
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摘要: The list below defines some of the basic terminology of the Android platform.
.apk file
Android application package file. Each Android application is compiled and packaged in a single file that includes all of the application's code (.dex files), resources, assets, and manifest file. The application package file can have any name but must use the .apk extension. For example: myExampleAppname.apk. For convenience, an application package file is often referred to as an ".apk".
Re
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摘要: C.__init__(self[, arg1, ...] )
Constructor (with any optional arguments)
C.__new__(self[, arg1, ...] )[a]
Constructor (with any optional argu ments); usually used for setting up subclassing of immutable data types
C.__del__(self)
Destructor
C.__str__(self)
Printable string representation; str() built-in and print statement
C.__repr__(self)
Evaluatable string representation; repr() built-in and '' operator
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摘要: 本来这是个老生常谈的问题，上周自成又分享了一些性能优化的建议，我这里再做一个全面的Tips整理，谨作为查阅型的文档，不妥之处，还请指正；
如果你已经对yahoo这些优化建议烂熟于心，果断点这里
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Five test auomation framework are discussed in this paper.
1) The Test Script Modularity Framework
2) The Test Library Architecture Framework
3) The Keyword-Driven or Table-Driven Testing Framework
4) The Data-Driven Testing Framework
5) The Hybrid Test Automation
摘要: 一、ASE(Android Scripting Environment)为Android系统带来了脚本语言的技术，通过它我们可以编辑和执行脚本，和脚本解释交互。脚本可以访问多数Android API,目前有一个开源项目叫做Scripting Layer for Android (SL4A) ，提供了对python,javaScript, Lua等脚本的支持。ASE主要通过两种方式来访问 Android API,一种是通过JSON-RPC来访问,另外一种通过BeanShell（Java语言的动态版本）直接访问Android API。SL4AL架构如下图：
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摘要: 2.你需要学习JAVA语言的基础知识以及它的核心类库 (collections，serialization，streams，networking， multithreading，reflection，event，handling，NIO，localization，以及其他)。
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1)
http://www.pythonchallenge.com/ 提供了不同level的Python题目，非常有趣的题目。做完一题后，把URL中的pc改为pcc可以看到上一题的答案
2)
http://projecteuler.net/ 里面有200多道题目，不要要求提交代码，只要最终答案，提供用各种语言来解决问题。这里（
http://dcy.is-programmer.com/posts/8750.html）有部分题目的答案
非常好玩，有兴趣的朋友，快来试试吧
看看 project euler 的第一道题：
If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below 1000.
用 python 语言写出来是：
print sum(i for i in xrange(1, 1000) if i % 3 == 0 or i % 5 == 0)
This is the first edition of what is expected to become a recurring series on InfoQ. The idea behind this minibook is that a number of InfoQ articles and interviews which deal with a particular topic (in this case, REpresentational State Transfer, or REST) are combined together to provide a detailed exploration suitable for both beginners and advanced practitioners.
Read More: http://www.infoq.com/minibooks/emag-03-2010-rest;jsessionid=1E2375E822D980824403DAD46588FAFE
摘要: #Trie Tree的基本特点
1）根节点不包含字符，除根节点外每个节点只包含一个字符
2）从根节点到某一个节点，路径上经过的字符连接起来，为该节点对应的字符串
3）每个节点的所有子节点包含的字符串不相同
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摘要: The Bloom filter, conceived by Burton Howard Bloom in 1970, is a space-efficient probabilistic data structure that is used to test whether an element is a member of a set.False positivesare possible, but false negatives are not. Elements can be added to the set, but not removed (though this can be addressed with a counting filter). The more elements that are added to the set, the larger the probability of false positives
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摘要: These posts have garnered a number of interesting comments. I want to address two of the negative ones in this post. Both are of the same general opinion that I am abandoning testers and that Google is not a nice place to ply this trade. I am puzzled by these comments because nothing could be further from the truth. One such negative comment I can take as a one-off but two smart people (hey they are reading this blog, right?) having this impression requires a rebuttal. Here are the comments:
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摘要: One of the key ways Google achieves good results with fewer testers than many companies is that we rarely attempt to ship a large set of features at once. In fact, the exact opposite is often the goal: build the core of a product and release it the moment it is useful to as large a crowd as feasible, then get their feedback and iterate. This is what we did with Gmail, a product that kept its beta tag for four years. That tag was our warning to users that it was still being perfected. We removed
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摘要: Lots of questions in the comments to the last two posts. I am not ignoring them. Hopefully many of them will be answered here and in following posts. I am just getting started on this topic.
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摘要: Android applications are, at least on the T-Mobile G1, limited to 16 MB of heap. It's both a lot of memory for a phone and yet very little for what some developers want to achieve. Even if you do not plan on using all of this memory, you should use as little as possible to let other applications run without getting them killed. The more applications Android can keep in memory, the faster it will be for the user to switch between his apps. As part of my job, I ran into memory leaks issues in Andr
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摘要: The Java community is now swamped with discussions about Oracle's patent suit against Google's Android platform. I've been contributing my opinion in several places, but there is one critical topic that needs repeating the same comments everywhere... so, this blog spills the beans once and completely.
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摘要: Activities in the system are managed as an activity stack. When a new activity is started, it is placed on the top of the stack and becomes the running activity -- the previous activity always remains below it in the stack, and will not come to the foreground again until the new activity exits.
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摘要: The one question I get more than any other is "How does Google test?" It's been explained in bits and pieces on this blog but the explanation is due an update
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摘要: Dependency injection asks us to separate the new operators from the application logic. This separation forces your code to have factories which are responsible for wiring your application together. However, better than writing factories, we want to use automatic dependency injection such as GUICE to do the wiring for us. But can DI really save us from all of the new operators?
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摘要: Everyone seems to think that they are writing OO after all they are using OO languages such as Java, Python or Ruby. But if you exam the code it is often procedural in nature
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By James Whittaker
I’ve had a number of questions about the SET role and it seems I have confused folks when I say that the SWE is a tester and the SET is a tester and at the same time the SWE is a developer and the SET is a developer. What could possibly be confusing about that?
Oh, yeah. Right.
My next series of posts are going to detail the role of the SET and all will eventually be clear but some clarification on career path seems worthwhile.
SETs are developers who write test code and automation as their primary task. They are in every sense of the word a developer. When we interview SETs, SWEs are on the interview loop and SWE questions are asked. They are not all of the interview, but they are part of it.
This means that the skill set that our SETs possess makes them perfect candidates for switching to the SWE role. There is neither incentive nor deterrent to do so. SETs and SWEs are on the same pay scale and bonus structure (I have both roles reporting to me so I have real visibility into salary data) and their promotion velocity (again based on actual data) is roughly equivalent. This means that SETs have no outside influences to prompt them one way or the other.
The key factor is really the type of work you are doing. SETs who find themselves involved in SWE work usually convert to SWE. SWEs are also drawn in the opposite direction. Much of this happens through our 20% time work. Any SET interested in SWE work can take on a 20% task doing feature development. Any SWE interested in automation can find a group and sign up for a 20%. Right now I have both SWEs and SETs involved in such cross pollination.
The ideal situation is that the title reflects the actual work that you are involved in. So if an SET starts doing more feature dev work than automation, he or she should convert, same for SWEs doing automation work. In my time here, conversions in both directions have happened, but it is not all that common. The work of both roles is engaging, interesting and intense. Few Googlers are walking around bored.
Bottom line: do the work you are passionate about and capable of and the right job title will find you.
一、概念
静态分派（Static Dispatch），发生在编译时期，分派是根据静态类型信息发生的，方法重载就是静态分派。
动态分派（Dynamic Dispatch），发生在运行时期，动态分派动态地置换掉某个方法。面向对象的语言用动态分派实现多态性。
Java语言支持静态多分派和动态的单分派，利用设计模式Java可以实现Double Dispatch，即访问者模式。
二、Visitor Pattern
目的：封装一些施加于某种数据结构元素之上的操作。
UML图：
主要原理：“反传球”，Element来Visitor之间二轮调用，调用过程中用sinlge dispatch确定类型
记录关于REST的一些技术：
1、REST简介：http://zh.wikipedia.org/zh/REST
2、InfoQ 深入浅出REST: http://www.infoq.com/cn/articles/rest-introduction
摘要: 要设计良好的架构，必须做到关注点分离，这样可以产生高内聚、低耦合的系统，这是美丽架构的终极原则
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摘要: A synchronization aid that allows a set of threads to all wait for each other to reach a common barrier point. CyclicBarriers are useful in programs involving a fixed sized party of threads that must occasionally wait for each other. The barrier is called cyclic because it can be re-used after the waiting threads are released.
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摘要: A java.util.concurrent.CountDownLatch is a concurrency construct that allows one or more threads to wait for a given set of operations to complete
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文章描述了实现 Multithreaded Servers的3种方法：
1）单线程，性能性差，请求等待时间长
2）多线程，把接受请求和处理请求的线程分开，接受后交给 worker处理
3）线程池，性能最佳，有效地防止负载过重，重复利用线程，请求多时，让请求排队接收处理
4）主要用socket来通信， ServerSocket 和 Socket
具体文章请看：http://tutorials.jenkov.com/java-multithreaded-servers/index.html
摘要: 软件模块之间总是存在着一定的接口，从调用方式上，可以把他们分为三类：同步调用、回调和异步调用。
同步调用是一种阻塞式调用，调用方要等待对方执行完毕才返回，它是一种单向调用，如HTTP；
回调是一种双向调用模式，也就是说，被调用方在接口被调用时也会调用对方的接口；
异步调用是一种类似消息或事件的机制，不过它的调用方向刚好相反，接口的服务在收到某种讯息或发生某种事件时，会主动通知客户方（即调用客户方的接口），如JMS；
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摘要: 虽然很少有 Java™ 开发人员能够忽视多线程编程和支持它的 Java 平台库，更少有人有时间深入研究线程。相反地，我们临时学习线程，在需要时向我们的工具箱添加新的技巧和技术。以这种方式构建和运行适当的应用程序是可行的，但是您可以做的不止这些。理解 Java 编译器的线程处理特性和 JVM 将有助于您编写更高效、性能更好的 Java 代码
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The Zen of Python, by Tim Peters
Beautiful is better than ugly.
Explicit is better than implicit.
Simple is better than complex.
Complex is better than complicated.
Flat is better than nested.
Sparse is better than dense.
Readability counts.
Special cases aren't special enough to break the rules.
Although practicality beats purity.
Errors should never pass silently.
Unless explicitly silenced.
In the face of ambiguity, refuse the temptation to guess.
There should be one-- and preferably only one --obvious way to do it.
Although that way may not be obvious at first unless you're Dutch.
Now is better than never.
Although never is often better than *right* now.
If the implementation is hard to explain, it's a bad idea.
If the implementation is easy to explain, it may be a good idea.
Namespaces are one honking great idea -- let's do more of those!
摘要: This is the text of the Commencement address by Steve Jobs, CEO of Apple Computer and of Pixar Animation Studios, delivered on June 12, 2005.
I am honored to be with you today at your commencement from one of the finest universities in the world. I never graduated from college. Truth be told, this is the closest I’ve ever gotten to a college graduation. Today I want to tell you three stories from my life. That’s it. No big deal. Just three stories.
The first story is about conn
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摘要: 1. 软件架构概述
1.1 什么是软件架构
◎ 软件架构的概念很混乱。如果你问五个不同的人，可能会得到五种不同的答案。
◎ 软件架构概念主要分为两大流派：
组成派：软件架构 = 组件 + 交互。
决策派：软件架构 = 重要决策集。
◎ 组成派和决策派的概念相辅相成。
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摘要: 所谓第一范式（1NF）是指数据库表的每一列都是不可分割的基本数据项，同一列中不能有多个值，即实体中的某个属性不能有多个值或者不能有重复的属性。如果出现重复的属性，就可能需要定义一个新的实体，新的实体由重复的属性构成，新实体与原实体之间为一对多关系。在第一范式（1NF）中表的每一行只包含一个实例的信息。简而言之，第一范式就是无重复的列。
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OS实时监控工具dstat，整合了vmstat, iostat, ifstat, netstat等常见os监控工具的优点，输出的结果简单直观，并且结果可以保存到csv文件。
dokie@ubuntu:~$ dstat
----total-cpu-usage---- -dsk/total- -net/total- ---paging-- ---system--
usr sys idl wai hiq siq| read writ| recv send| in out | int csw
14 5 78 3 0 0| 553k 109k| 0 0 | 83B 989B| 983 2190
8 2 90 0 0 0| 0 0 |2076B 1383B| 0 0 |1076 1407
9 3 89 0 0 0| 0 72k|7530B 420B| 0 0 | 721 1501
9 4 87 0 0 0| 0 0 |9547B 564B| 0 0 | 750 1474
8 2 89 0 0 0| 0 0 | 12k 672B| 0 0 | 772 1681
9 2 89 0 0 0| 0 0 | 13k 792B| 0 0 | 677 1396
dokie@ubuntu:~$ dstat -h
Usage: dstat [-afv] [options..] [delay [count]]
Versatile tool for generating system resource statistics
Dstat options:
-c, --cpu enable cpu stats
-C 0,3,total include cpu0, cpu3 and total
-d, --disk enable disk stats
-D total,hda include hda and total
-g, --page enable page stats
-i, --int enable interrupt stats
-I 5,eth2 include int5 and interrupt used by eth2
-l, --load enable load stats
-m, --mem enable memory stats
-n, --net enable network stats
-N eth1,total include eth1 and total
-p, --proc enable process stats
-r, --io enable io stats (I/O requests completed)
-s, --swap enable swap stats
-S swap1,total include swap1 and total
-t, --time enable time/date output
-T, --epoch enable time counter (seconds since epoch)
-y, --sys enable system stats
--aio enable aio stats
--fs enable fs stats
--ipc enable ipc stats
--lock enable lock stats
--raw enable raw stats
--socket enable socket stats
--tcp enable tcp stats
--udp enable udp stats
--unix enable unix stats
--vm enable vm stats
-M stat1,stat2 enable external plugins
--mods stat1,stat2
--list list all internal and external plugins
-a, --all equals -cdngy (default)
-f, --full expand -C, -D, -I, -N and -S discovery lists
-v, --vmstat equals -pmgdsc -D total
--integer show integer values
--nocolor disable colors (implies --noupdate)
--noheaders disable repetitive headers
--noupdate disable intermediate updates
--output file write CSV output to file
delay is the delay in seconds between each update
count is the number of updates to display before exiting
The default delay is 1 and count is unspecified (unlimited)
常用的命令：dstat -cdlmnpsy
导出为CVS:
dstat -ta --output osstat.csv
1. 安装JDK
http://wiki.ubuntu.org.cn/Java%E5%AE%89%E8%A3%85%E9%85%8D%E7%BD%AE
2. 安装Python
1). apt-get install python
2). PyDev for eclipse:
Name：PyDev，Location：http://pydev.org/updates
Ref:http://www.cnblogs.com/Realh/archive/2010/10/10/1847251.html
3. 安装dstat--性能监测工具
apt-get install dstat
下面是来自 Taobao QA Team中的安全测试方面的文章，对初学者很有指导意义
安全测试学习笔记系列：
1. http://qa.taobao.com/?p=11352
2.http://qa.taobao.com/?p=11363
3.http://qa.taobao.com/?p=11472
4.http://qa.taobao.com/?p=11479
5.http://qa.taobao.com/?p=11484
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WEB漏洞攻击之SQL注入:http://qa.taobao.com/?p=11403
摘要: onabort 当用户中断下载图像时触发。
onactivate 当对象设置为活动元素时触发。
onafterprint 对象所关联的文档打印或打印预览后立即在对象上触发。
onafterupdate 当成功更新数据源对象中的关联对象后在数据绑定对象上触发。
onbeforeactivate new 对象要被设置为当前元素前立即触发。
onbeforecopy 当选中区复制到系统剪贴板之前在源对象触发。
onbeforecut 当选中区从文档中删除之前在源对象触发。
onbeforedeactivate 在 activeElement 从当前对象变为父文档其它对象之前立即触发。
onbeforeeditfocus 在包含于可编辑元素内的对象进入用户界面激活状态前或可编辑容器变成控件选中区前触发。
onbeforepaste 在选中区从系统剪贴板粘贴到文档前在目标对象上触发。
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数组类Array是Java中最基本的一个存储结构。它用于存储一组连续的对象或基本类型的数据。其中的元素的类型必须相同。
Array是最有效率的一 种：
1、效率高，但容量固定且无法动态改变。 Array还有一个缺点是，无法判断其中实际存有多少元素，length只是告诉我们Array的容量。
2、Java中有一个Arrays类，专门用来操作Array，提供搜索、排序、复制等静态方法。 equals()：比较两个Array是否相等，Array拥有相同元素个数，且所有对应元素两两相等。 fill()：将值填入Array中。 sort()：用来对Array进行排序。 binarySearch()：在排好序的Array中寻找元素。 System.arraycopy()：Array的复制。
Java Collections Framework成员主要包括两种类型，即：Collection和Map类型。 在Java中提供了Collection和Map接口。其中List和Set继承了Collection接口；Vector、ArrayList、 LinkedList三个类实现List接口，HashSet、TreeSet实现Set接口，HashTable、HashMap、 TreeMap实现Map接口。由此可见，Java中用8种类型的基本数据结构来实现其Collections Framework；下面分别进行介绍。
Vector：基于Array的List，性能也就不可能超越Array，并且Vector是"sychronized"的，这个也是Vector和ArrayList的唯一的区别。
ArrayList：同Vector一样是一个基于Array的，但是不同的是ArrayList不是同步的。所以在性能上要比Vector优越一些，但 是当运行到多线程环境中时，可需要自己在管理线程的同步问题。从其命名中可以看出它是一种类似数组的形式进行存储，因此它的随机访问速度极快。
LinkedList：LinkedList不同于前面两种List，它不是基于Array的，所以不受Array性能的限制。它每一个节点（Node） 都包含两方面的内容：
1、节点本身的数据（data）；
2、下一个节点的信息（nextNode）。所以当对LinkedList做添加，删除动作的时候 就不用像基于Array的List一样，必须进行大量的数据移动。只要更改nextNode的相关信息就可以实现了所以它适合于进行频繁进行插入和删除操 作。这就是LinkedList的优势。Iterator只能对容器进行向前遍历，而 ListIterator则继承了Iterator的思想，并提供了对List进行双向遍历的方法。
List总结：
1、所有的List中只能容纳单个不同类型的对象组成的表，而不是Key－Value键值对。例如：[ tom,1,c ]；
2、所有的List中可以有相同的元素，例如Vector中可以有 [ tom,koo,too,koo ]；
3、所有的List中可以有null元素，例如[ tom,null,1 ]；
4、基于Array的List（Vector，ArrayList）适合查询，而LinkedList（链表）适合添加，删除操作。
HashSet：虽然Set同List都实现了Collection接口，但是他们的实现方式却大不一样。List基本上都是以Array为基础。但是 Set则是在HashMap的基础上来实现的，这个就是Set和List的根本区别。HashSet的存储方式是把HashMap中的Key作为Set的 对应存储项，这也是为什么在Set中不能像在List中一样有重复的项的根本原因，因为HashMap的key是不能有重复的。HashSet能快速定位 一个元素，但是放到HashSet中的对象需要实现hashCode()方法0。
TreeSet则将放入其中的元素按序存放，这就要求你放入其中的对象是可排序的，这就用到了集合框架提供的另外两个实用类Comparable和 Comparator。一个类是可排序的，它就应该实现Comparable接口。有时多个类具有相同的排序算法，那就不需要重复定义相同的排序算法，只要实现Comparator接口即可。TreeSet是SortedSet的子类，它不同于HashSet的根本就是TreeSet是有序的。它是通过SortedMap来实现的。
Set总结：
1、Set实现的基础是Map（HashMap）；
2、Set中的元素是不能重复的，如果使用add(Object obj)方法添加已经存在的对象，则会覆盖前面的对象； Set里的元素是不能重复的，那么用什么方法来区分重复与否呢? 是用==还是equals()? 它们有何区别? Set里的元素是不能重复的，即不能包含两个元素e1、e2（e1.equals（e2））。那么用iterator()方法来区分重复与否。 equals()是判读两个Set是否相等。==方法决定引用值(句柄)是否指向同一对象。
HashMap、TreeMap、Hashtable：
1、HashMap也用到了哈希码的算法，以便快速查找一个键，TreeMap则是对键按序存放，因此它有一些扩展的方法，比如 firstKey(),lastKey()等。
2、Hashtable：不允许空（null）键（key）或值（value），Hashtable的方法是Synchronize的，在多个线程访问 Hashtable时，不需要自己为它的方法实现同步，而HashMap 就必须为之提供外同步。 Hashtable和HashMap采用的hash/rehash算法都大概一样，所以性能不会有很大的差异。
3、HashMap和Hashtable的区别：HashMap是Hashtable(线程案例的)的轻量级实现（非线程安全的实现），他们都完成了Map接口。主要区别在于HashMap允许空（null）键（key）或值（value）,非同步，由于非线程安全，效率上可能高于Hashtable。
Map总结：
是一种把键对象和值对象进行关联的容器，Map有两种比较常用的实现： HashTable、HashMap和TreeMap。