README.md

Clean Code - Functions - Testable Html

This repository show how to refactor a big function to a more readable code code step by step from Uncle Bob (UB) who is the author of Clean Code.

Flowing this repository will let you know following questions ?

• How big should a function be? 20 Lines? A screenful? Is there a way to know if your functions are the right size?

• Object Oriented Design involves the art of breaking applications into classes. But have you found all the classes in the design of your application? Is there a way to know?

• Functions are supposed to do "One Thing", do it well, and do it only. But what is "One Thing". Is there a way to tell if your functions are obeying that rule?

• The answer to all these questions is yes! And not just with some fuzzy hand-waving platitudes either. There are fool-proof and unambiguous answers to these questions.

Install

step1: clone this repo:

git clone https://github.com/classtag/clean_code_functions_testable_html.git

step2: import the repo into your IDEA, then add jars in lib folder into classpath.

Refactor History

• init with no-refactored code
• extract the function to a class
• extract the duplicated get crawler logic into a class field , initial it at construct method
• extract mode variable
• extract includePage function for 4 same block
• use String.format replace String + String
• extract includeIfInherited function
• extract includeSetups and includeTearDowns functions
• cut the StringBuffer with funcitons return string
• merge the if block into one together
• extract isTestPage function for more readable code
• extract surroundPageWithSetupsAndTeardowns functions
• rename the class name and invoke name more meaningful

These bellow refactor history shows how to refactor a big fucntion into very small functions. It makes sure each function just do one thing, and simple, very nice for reading.

run command git hist to see the refactor history.

* 0a59fcd <anduo> (HEAD -> master) (13 seconds ago)
|         rename the class name and invoke name more meaningful
* 3cf27c4 <anduo> (2 minutes ago)
|         extract surroundPageWithSetupsAndTeardowns functions
* a9aa5f3 <anduo> (4 minutes ago)
|         extract isTestPage function for more readable code
* 93d53e2 <anduo> (5 minutes ago)
|         merge the if block into one together
* 29d061c <anduo> (6 minutes ago)
|         cut the stringbuffer with funcitons return string
* 78d7bf6 <anduo> (14 minutes ago)
|         extract includeSetups and includeTearDowns functions
lines 1-12...skipping...
* 0a59fcd <anduo> (HEAD -> master) (13 seconds ago)
|         rename the class name and invoke name more meaningful
* 3cf27c4 <anduo> (2 minutes ago)
|         extract surroundPageWithSetupsAndTeardowns functions
* a9aa5f3 <anduo> (4 minutes ago)
|         extract isTestPage function for more readable code
* 93d53e2 <anduo> (5 minutes ago)
|         merge the if block into one together
* 29d061c <anduo> (6 minutes ago)
|         cut the stringbuffer with funcitons return string
* 78d7bf6 <anduo> (14 minutes ago)
|         extract includeSetups and includeTearDowns functions
* 26370b9 <anduo> (21 minutes ago)
|         extract includeIfInherited function
* 9720018 <anduo> (24 minutes ago)
|         use String.format replace String + String
* e128112 <anduo> (25 minutes ago)
|         extract includePage function for 4 same block
* 436fbd7 <anduo> (27 minutes ago)
|         extract mode variable
* 606332f <anduo> (32 minutes ago)
|         extract the duplicated get crawler logic into a class field , initial it
|         at construct method
* 5ce25d5 <anduo> (35 minutes ago)
|         extract common variable into construct method
* d1b8e50 <anduo> (49 minutes ago)
|         extract the function to a class
* 091dd74 <anduo> (54 minutes ago)
          init with no-refactored code

The full version of the refactor steps can find at history

Thanks

More rules about clean code - functions can find at clean-code-episode-3