Golang设计模式之组合模式

创建文件：Component.go

package Composite

//有的时候是父节点，叶子
type Component interface {
    Parent() Component
    SetParent(Component)
    Name() string
    SetName(string)
    AddChild(Component)
    Print(string)
}

const (
    LeafNode = iota
    CompositeNode
)

type component struct {
    parent Component
    name   string
}

func NewComponent(kind int, name string) Component {
    var c Component
    switch kind {
    case LeafNode: //根据不同的类型
        c = NewLeaf()
    case CompositeNode:
        c = NewComposite()
    }
    c.SetName(name)
    return c
}

func (c *component) Parent() Component {
    return c.parent
}

func (c *component) SetParent(parent Component) {
    c.parent = parent
}

func (c *component) Name() string {
    return c.name
}

func (c *component) SetName(name string) {
    c.name = name
}

func (c *component) AddChild(child Component) {

}

func (c *component) Print(string2 string) {

}

创建文件：Leafs.go

package Composite

import "fmt"

type Leaf struct {
    component
}

func NewLeaf() *Leaf { // 开辟一个叶子
    return &Leaf{}
}

func (c *Leaf) Print(pre string) {
    fmt.Println(pre, c.Name())
}

type Composite struct {
    component
    childs []Component // 叶子集合
}

// 创建一个组合结构体
func NewComposite() *Composite {
    return &Composite{childs: make([]Component, 0)}
}

func (c *Composite) AddChild(child Component) {
    child.SetParent(c)
    c.childs = append(c.childs, child)
}

func (c *Composite) Print(pre string) { // 打印显示每一个节点
    fmt.Println(pre, c.name)
    pre += "   "
    for _, comp := range c.childs {
        comp.Print(pre)
    }
}

main.go

package main

import "test/design/Composite"

func main() {
    root := Composite.NewComponent(Composite.CompositeNode, "root")
    r1 := Composite.NewComponent(Composite.CompositeNode, "r1")
    r2 := Composite.NewComponent(Composite.CompositeNode, "r2")
    r3 := Composite.NewComponent(Composite.CompositeNode, "r3")

    l1 := Composite.NewComponent(Composite.LeafNode, "l1")
    l2 := Composite.NewComponent(Composite.LeafNode, "l2")
    l3 := Composite.NewComponent(Composite.LeafNode, "l3")

    root.AddChild(r1)
    root.AddChild(r2)
    root.AddChild(r3)

    r1.AddChild(l1)
    r2.AddChild(l2)
    r3.AddChild(l3)

    root.Print("")
}