Merge pull request mouredev#4976 from hozlucas28/Solution-29-TypeScript

#29 - TypeScript

Roadmap/29 - SOLID ISP/typescript/hozlucas28.ts

@@ -0,0 +1,238 @@
+/*
+    Interface Segregation Principle (ISP)...
+*/
+
+console.log('Interface Segregation Principle (ISP)...')
+
+interface IBadAnimal {
+    fly: () => void
+    run: () => void
+    swim: () => void
+}
+
+class BadDog implements IBadAnimal {
+    fly(): void {
+        throw new Error('A dog can not fly')
+    }
+
+    run(): void {
+        console.log('The dog is running!')
+    }
+
+    swim(): void {
+        console.log('The dog is swimming!')
+    }
+}
+
+class BadDuck implements IBadAnimal {
+    fly(): void {
+        console.log('The duck is flying!')
+    }
+
+    run(): void {
+        console.log('The duck is running!')
+    }
+
+    swim(): void {
+        console.log('The duck is swimming!')
+    }
+}
+
+console.log('\nBad implementation of Interface Segregation Principle (ISP)...')
+
+console.log(`\n\`\`\`\ninterface IBadAnimal {
+    fly: () => void
+    run: () => void
+    swim: () => void
+}
+
+class BadDog implements IBadAnimal {
+    fly(): void {
+        throw new Error('A dog can not fly')
+    }
+
+    run(): void {
+        console.log('The dog is running!')
+    }
+
+    swim(): void {
+        console.log('The dog is swimming!')
+    }
+}
+
+class BadDuck implements IBadAnimal {
+    fly(): void {
+        console.log('The duck is flying!')
+    }
+
+    run(): void {
+        console.log('The duck is running!')
+    }
+
+    swim(): void {
+        console.log('The duck is swimming!')
+    }
+}\n\`\`\``)
+
+console.log(
+    '\nThis is a bad implementation of Interface Segregation Principle (ISP),\n' +
+        'because the "BadDog" class should not implement an interface with methods\n' +
+        'that it is going to never use. So, the implemented interface ("IBadAnimal")\n' +
+        'is to general for the "BadDog" class, but perfect for the "BadDuck" class.'
+)
+
+console.log('\nGood implementation of Interface Segregation Principle (ISP)...')
+
+interface IAerialAnimal {
+    fly: () => void
+}
+
+interface IAquaticAnimal {
+    swim: () => void
+}
+
+interface ITerrestrialAnimal {
+    run: () => void
+}
+
+class GoodDog implements ITerrestrialAnimal, IAquaticAnimal {
+    run(): void {
+        console.log('The dog is running!')
+    }
+
+    swim(): void {
+        console.log('The dog is swimming!')
+    }
+}
+
+class GoodDuck implements IAerialAnimal, IAquaticAnimal, ITerrestrialAnimal {
+    fly(): void {
+        console.log('The duck is flying!')
+    }
+
+    run(): void {
+        console.log('The duck is running!')
+    }
+
+    swim(): void {
+        console.log('The duck is swimming!')
+    }
+}
+
+console.log(`\n\`\`\`\ninterface IAerialAnimal {
+    fly: () => void
+}
+
+interface IAquaticAnimal {
+    swim: () => void
+}
+
+interface ITerrestrialAnimal {
+    run: () => void
+}
+
+class GoodDog implements ITerrestrialAnimal, IAquaticAnimal {
+    run(): void {
+        console.log('The dog is running!')
+    }
+
+    swim(): void {
+        console.log('The dog is swimming!')
+    }
+}
+
+class GoodDuck implements IAerialAnimal, IAquaticAnimal, ITerrestrialAnimal {
+    fly(): void {
+        console.log('The duck is flying!')
+    }
+
+    run(): void {
+        console.log('The duck is running!')
+    }
+
+    swim(): void {
+        console.log('The duck is swimming!')
+    }
+}\n\`\`\``)
+
+console.log(
+    '\nThis is a good implementation of Interface Segregation Principle (ISP),\n' +
+        'because the "GoodDog" class only implements the necessary methods, without\n' +
+        'any extras. Also, the "GoodDuck" class utilizes an interface perfectly suited\n' +
+        'to its needs, with no extra methods.'
+)
+
+console.log(
+    '\n# ---------------------------------------------------------------------------------- #\n'
+)
+
+/*
+    Additional challenge...
+*/
+
+console.log('Additional challenge...')
+
+interface IBlackAndWhitePrinter {
+    print: () => void
+}
+
+class BlackAndWhitePrinter implements IBlackAndWhitePrinter {
+    constructor() {}
+
+    print(): void {
+        console.log('Paper printed in black and white!')
+    }
+}
+
+interface IColorPrinter {
+    print: () => void
+}
+
+class ColorPrinter implements IColorPrinter {
+    constructor() {}
+
+    print(): void {
+        console.log('Paper printed in color!')
+    }
+}
+
+interface IMultifunctionalPrinter extends IBlackAndWhitePrinter, IColorPrinter {
+    scan: () => void
+    sendFax: () => void
+}
+
+class MultifunctionalPrinter implements IMultifunctionalPrinter {
+    constructor() {}
+
+    print(): void {
+        console.log('Paper printed!')
+    }
+
+    scan(): void {
+        console.log('Scan completed!')
+    }
+
+    sendFax(): void {
+        console.log('Fax sent!')
+    }
+}
+
+const blackAndWhitePrinter: BlackAndWhitePrinter = new BlackAndWhitePrinter()
+const colorPrinter: ColorPrinter = new ColorPrinter()
+const multifunctionalPrinter: MultifunctionalPrinter =
+    new MultifunctionalPrinter()
+
+console.log()
+blackAndWhitePrinter.print()
+
+console.log()
+colorPrinter.print()
+
+console.log()
+multifunctionalPrinter.print()
+
+console.log()
+multifunctionalPrinter.scan()
+
+console.log()
+multifunctionalPrinter.sendFax()