Duplicate code smell
From CSSEMediaWiki
(Difference between revisions)
m |
|||
| Line 1: | Line 1: | ||
| − | Duplicated code is the smelliest of the code smells. The book | + | Duplicated code is the smelliest of the code smells. The book ''Refactoring'' [[Martin Fowler 1999]] states that: "If you see the same code structure in more than one place, you can be sure that your program will be better if you find a way to unify them." [[Martin Fowler 1999]] states that the simplest duplicated code problem is when you have the same expression in two methods of the same class. |
| + | |||
| + | == Refactoring == | ||
| + | |||
| + | The best way to fix this bad code smell is to use [[Extract Method]] as shown below. | ||
printOwing() { | printOwing() { | ||
| Line 24: | Line 28: | ||
* [[Don't repeat yourself]] | * [[Don't repeat yourself]] | ||
* [[Once and only once]] | * [[Once and only once]] | ||
| + | * [[Code smells]] | ||
| + | * [[Refactoring]] | ||
Revision as of 22:33, 29 July 2008
Duplicated code is the smelliest of the code smells. The book Refactoring Martin Fowler 1999 states that: "If you see the same code structure in more than one place, you can be sure that your program will be better if you find a way to unify them." Martin Fowler 1999 states that the simplest duplicated code problem is when you have the same expression in two methods of the same class.
Refactoring
The best way to fix this bad code smell is to use Extract Method as shown below.
printOwing() {
printBanner();
//print details
System.out.println ("name: " + _name);
System.out.println ("amount " + getOutstanding());
}
becomes
void printOwing() {
printBanner();
printDetails(getOutstanding());
}
void printDetails (double outstanding) {
System.out.println ("name: " + _name);
System.out.println ("amount " + outstanding);
}
