Clean CodeWhisnu | Vox Teneo Indonesia

Reason?

• We Are Programmer• We Want to be a Better Programmer

A = 1B = A

Print BA = 1C = AB = C

Print B - Same Task- Same Effort- Same Test Result- No BUG’s

Who’s code you choose?

Who’s code you choose?

Does it matter how the code is written?

or does it only matter that it works?

Good Code Matterbecause it doesn't end there!

• You Will Have To Go Back• Someone Else Will Have To Go Back• They Don’t Teach That in School• Good Code Matter• Definition• Degrees of Bad• The Netscape Fallacy• Why Write Good Code• But Doesn't Good Code Cost More Up Front?

Boy Scout RuleLeave the campground cleaner than you found it.

CLEAN CODE = WTF’sMinutes

Meaningful NamesFunctions

CommentsFormatting

Objects and Data StructuresError Handling

Unit Tests

Meaningful Names

int d; // elapsed time in days

string htmlOutput; // form configuration html

DataGrid dataGrid1;

DataGrid dataGrid2;

Label label1;

Object myObj;int elapsedTimeInDays;

string formConfiguration;

DataGrid dgCustomers;

DataGrid dgProducts;

Label lblFirstName;

Object objCustomer;

Functions

• Small and Should be smaller than that• Do One Thing• One Level of Abstraction

• getHtml();• String pagePathName = PathParser.render(path);• .append(“\n”);

• Switch Statement (break it for SRP/OCP reason)• Ideal number of arguments is ZERO• Object Argument (hidden dependency, inject dependency, SRP)• Have No Side Effect (setAndCheckIfExists())

Comment

• Don’t Comment Bad Code!• Explain on Code• Legal comment, TODO comment, JavaDoc, PHPDocumenter• Clarification• Warning of Consequences• No Mumbling• Redudant Comment• Position Marker• Closing Brace comment• Attributes and ByLine• Comment Out Code (your note code)

Formating

• The Purpose of Formatting?• Vertical Matter, Horizontal Alignment• Breaking Identation• Team Rules

Object and Data Structures*

• The Law Of Demeter (Train Wrecks)

* lol + \m/ =

Error Handling

• Prefer Returning an Exceptions• Don’t Return null

Unit Tests

The Three Laws of TDD:• First Law You may not write production code until you have written a

failing unit test.• Second Law You may not write more of a unit test than is sufficient to

fail, and not compiling is failing.• Third Law You may not write more production code than is sufficient

to pass the currently failing test.

In Practice it’s all about RTM

READABILITYTESTABILITY

MAINTAINABILITY

From STUPID to SOLID

S T UPI D

SingletonTight Coupling

UntestabilityPremature Optimization

Indescriptive NamingDuplication

SingletonTight Coupling

UntestabilityPremature Optimization

Indescriptive NamingDuplication

SingletonTight Coupling

UntestabilityPremature Optimization

Indescriptive NamingDuplication

SingletonTight Coupling

UntestabilityPremature Optimization

Indescriptive NamingDuplication

SingletonTight Coupling

UntestabilityPremature Optimization

Indescriptive NamingDuplication

SingletonTight Coupling

UntestabilityPremature Optimization

Indescriptive NamingDuplication

SingletonTight Coupling

UntestabilityPremature Optimization

Indescriptive NamingDuplication

S OL I D

Single Responsibility PrincipleOpen/Close Principle

Liskov Substitution PrincipleInterface Segregation Principle

Dependency Inversion Principle

Single Responsibility PrincipleOpen/Close Principle

Liskov Substitution PrincipleInterface Segregation Principle

Dependency Inversion Principle

Single Responsibility PrincipleOpen/Close Principle

Liskov Substitution PrincipleInterface Segregation Principle

Dependency Inversion Principle

Single Responsibility PrincipleOpen/Close Principle

Liskov Substitution PrincipleInterface Segregation Principle

Dependency Inversion Principle

Single Responsibility PrincipleOpen/Close Principle

Liskov Substitution PrincipleInterface Segregation Principle

Dependency Inversion Principle

Single Responsibility PrincipleOpen/Close Principle

Liskov Substitution PrincipleInterface Segregation Principle

Dependency Inversion Principle

For Coding Standard ?

…and any Questions?