建造者模式go语言

将一个复杂对象的构建分离成多个简单对象的构建组合

builder.go

package builder

//Builder 是生成器接口
type Builder interface {
    Part1()
    Part2()
    Part3()
}

type Director struct {
    builder Builder
}

// NewDirector ...
func NewDirector(builder Builder) *Director {
    return &Director{
        builder: builder,
    }
}

//Construct Product
func (d *Director) Construct() {
    d.builder.Part1()
    d.builder.Part2()
    d.builder.Part3()
}

type Builder1 struct {
    result string
}

func (b *Builder1) Part1() {
    b.result += "1"
}

func (b *Builder1) Part2() {
    b.result += "2"
}

func (b *Builder1) Part3() {
    b.result += "3"
}

func (b *Builder1) GetResult() string {
    return b.result
}

type Builder2 struct {
    result int
}

func (b *Builder2) Part1() {
    b.result += 1
}

func (b *Builder2) Part2() {
    b.result += 2
}

func (b *Builder2) Part3() {
    b.result += 3
}

func (b *Builder2) GetResult() int {
    return b.result
}

builder_test.go

package builder

import "testing"

func TestBuilder1(t *testing.T) {
    builder := &Builder1{}
    director := NewDirector(builder)
    director.Construct()
    res := builder.GetResult()
    if res != "123" {
        t.Fatalf("Builder1 fail expect 123 acture %s", res)
    }
}

func TestBuilder2(t *testing.T) {
    builder := &Builder2{}
    director := NewDirector(builder)
    director.Construct()
    res := builder.GetResult()
    if res != 6 {
        t.Fatalf("Builder2 fail expect 6 acture %d", res)
    }
}