feat: Builder pattern

Author: pawlobanano

.gitignore

@@ -1,5 +1,7 @@
 abstract-factory
+builder
 simple-factory
 
 !abstract-factory/
+!builder/
 !simple-factory/

Makefile

@@ -1,7 +1,10 @@
 abstract-factory:
 	go build -o abstract-factory ./creational/abstract-factory && ./abstract-factory
 
+builder:
+	go build -o builder ./creational/builder && ./builder
+
 simple-factory:
 	go build -o simple-factory ./creational/simple-factory && ./simple-factory
 
-.PHONY: abstract-factory simple-factory
+.PHONY: abstract-factory builder simple-factory

creational/builder/builderer.go

@@ -0,0 +1,19 @@
+package main
+
+type Builderer interface {
+	setWindowType()
+	setDoorType()
+	setFloors()
+	build() House
+}
+
+func getHouseBuilder(builderType string) Builderer {
+	switch builderType {
+	case "normal":
+		return newNormalHouseBuilder()
+	case "igloo":
+		return nil
+	default:
+		return &Dummy{}
+	}
+}

creational/builder/constructionManager.go

@@ -0,0 +1,23 @@
+package main
+
+type ConstructionManager struct {
+	houseBuilder Builderer
+}
+
+func newConsturtionManager(b Builderer) *ConstructionManager {
+	return &ConstructionManager{
+		houseBuilder: b,
+	}
+}
+
+func (cM ConstructionManager) setHouseBuilder(b Builderer) {
+	cM.houseBuilder = b
+}
+
+func (cM ConstructionManager) buildHouse() House {
+	cM.houseBuilder.setDoorType()
+	cM.houseBuilder.setWindowType()
+	cM.houseBuilder.setFloors()
+
+	return cM.houseBuilder.build()
+}

creational/builder/dummy.go

@@ -0,0 +1,21 @@
+package main
+
+type Dummy struct {
+	house House
+}
+
+func (d *Dummy) setWindowType() {
+	d.house.windowType = ""
+}
+
+func (d *Dummy) setDoorType() {
+	d.house.doorType = ""
+}
+
+func (d *Dummy) setFloors() {
+	d.house.floors = 0
+}
+
+func (a *Dummy) build() House {
+	return House{}
+}

creational/builder/house.go

@@ -0,0 +1,7 @@
+package main
+
+type House struct {
+	windowType string
+	doorType   string
+	floors     int
+}

creational/builder/main.go

@@ -0,0 +1,14 @@
+package main
+
+import "fmt"
+
+func main() {
+	normalHouseBuilder := getHouseBuilder("normall")
+
+	constructionManager := newConsturtionManager(normalHouseBuilder)
+	normalHouse := constructionManager.buildHouse()
+
+	fmt.Printf("Normal house door type: %s\n", normalHouse.doorType)
+	fmt.Printf("Normal house window type: %s\n", normalHouse.windowType)
+	fmt.Printf("Normal house floors: %d\n", normalHouse.floors)
+}

creational/builder/normalHouseBuilder.go

@@ -0,0 +1,31 @@
+package main
+
+type NormalHouseBuilder struct {
+	windowType string
+	doorType   string
+	floors     int
+}
+
+func newNormalHouseBuilder() *NormalHouseBuilder {
+	return &NormalHouseBuilder{}
+}
+
+func (b *NormalHouseBuilder) setWindowType() {
+	b.windowType = "Wooden window"
+}
+
+func (b *NormalHouseBuilder) setDoorType() {
+	b.doorType = "Wooden door"
+}
+
+func (b *NormalHouseBuilder) setFloors() {
+	b.floors = 2
+}
+
+func (b *NormalHouseBuilder) build() House {
+	return House{
+		doorType:   b.doorType,
+		windowType: b.windowType,
+		floors:     b.floors,
+	}
+}