How do you refactor a switch statement?

Apply the Replace Type Code with Subclasses refactoring:

  1. Add subclasses for each type represented by the type code.
  2. Use a factory method to create the subclass objects based on the type.
  3. Apply Push Down Method by moving the switch-statement-abusing methods to the subclasses.

What is JavaScript refactoring?

What Is Refactoring in JavaScript? Refactoring—in JavaScript and other languages as well—is the process of changing a piece of code without altering how it works. In other words: you play around with the internal structure of a given function, class, module, etc., without changing the results it produces.

Are there switch statements in JavaScript?

The switch statement is a part of JavaScript’s “Conditional” Statements, which are used to perform different actions based on different conditions. Use switch to select one of many blocks of code to be executed.

Do switch statements need break JavaScript?

It is not necessary to break the last case in a switch block. The block breaks (ends) there anyway. Note: If you omit the break statement, the next case will be executed even if the evaluation does not match the case.

How do you refactor a switch statement in Java?

Seven Ways to Refactor Java switch Statements

  1. Implementing the Strategy Pattern via Java Enum. Application Name: SwitchToStrategyEnum.
  2. Implementing the Command Pattern.
  3. Using the Java 8+ Supplier.
  4. Defining a Custom Functional Interface.
  5. Relying on Abstract Factory.
  6. Implementing a State Pattern.

How do you replace a switch with polymorphism?

Replace Conditional with Polymorphism

  1. Step 1 is to make sure the switch statement is in a method of its own.
  2. Step 3 is to create a subclass for each leg of the conditional, overriding the parent calculateRate method.
  3. Step 4 is to turn ProjectRateType into either an interface or abstract class.

How do you refactor a function?

  1. 4 Principles When Refactoring Your Functions. Improve your code’s readability.
  2. Remove Duplication. The first obstacle that many junior programmers have is that they don’t know when to refactor functions.
  3. Keep Them Small.
  4. Give Meaningful Names.
  5. Minimize the Number of Parameters.

What is switch statement example?

A general syntax of how switch-case is implemented in a ‘C’ program is as follows: switch( expression ) { case value-1: Block-1; Break; case value-2: Block-2; Break; case value-n: Block-n; Break; default: Block-1; Break; } Statement-x; The expression can be integer expression or a character expression.

Do switch statements need default?

No it is not necessary of default case in a switch statement and there is no rule of keeping default case at the end of all cases it can be placed at the starting andd middle of all other cases.

Is break optional in switch statement?

The break statement is used inside the switch to terminate a statement sequence. The break statement is optional. If omitted, execution will continue on into the next case. The default statement is optional and can appear anywhere inside the switch block.

Is Break necessary in switch?

Answer. Use of break statement in a switch case statement is optional. Omitting break statement will lead to fall through where program execution continues into the next case and onwards till end of switch statement is reached.