go知识重新整理

Go/DesignPattern/visitor/visitor.go

@@ -0,0 +1,88 @@
+/**
+* @Author:zhoutao
+* @Date:2020/12/12 下午4:12
+* @Desc:
+ */
+
+package visitor
+
+import "fmt"
+
+//访问者模式： 可以给一系列对象透明的添加功能，并且把相关代码封装到一个类中
+//对象只要预留访问者接口Accept，则在后期为独享添加功能的时候就不需要改动对象了
+
+type Customer interface {
+	Accept(Visitor)
+}
+
+type Visitor interface {
+	Visit(Customer)
+}
+
+type CustomerCol struct {
+	customers []Customer
+}
+
+func (c *CustomerCol) Add(customer Customer) {
+	c.customers = append(c.customers, customer)
+}
+
+func (c *CustomerCol) Accept(visitor Visitor) {
+	for _, customer := range c.customers {
+		customer.Accept(visitor)
+	}
+}
+
+//New EnterpriseCustomer
+func NewEnterpriseCustomer(name string) *EnterpriseCustomer {
+	return &EnterpriseCustomer{
+		name: name,
+	}
+}
+
+type EnterpriseCustomer struct {
+	name string
+}
+
+func (c *EnterpriseCustomer) Accept(visitor Visitor) {
+	visitor.Visit(c)
+}
+
+//New IndividualCustomer
+func NewIndividualCustomer(name string) *IndividualCustomer {
+	return &IndividualCustomer{
+		name: name,
+	}
+}
+
+type IndividualCustomer struct {
+	name string
+}
+
+func (i *IndividualCustomer) Accept(visitor Visitor) {
+	visitor.Visit(i)
+}
+
+//
+type ServiceRequestVisitor struct {
+}
+
+func (s *ServiceRequestVisitor) Visit(customer Customer) {
+	switch c := customer.(type) {
+	case *EnterpriseCustomer:
+		fmt.Printf("serving enterprise customer %s\n", c.name)
+	case *IndividualCustomer:
+		fmt.Printf("serving Individual customer %s\n", c.name)
+	}
+}
+
+//
+type AnalisisVisitor struct {
+}
+
+func (*AnalisisVisitor) Visit(customer Customer) {
+	switch c := customer.(type) {
+	case *EnterpriseCustomer:
+		fmt.Printf("analysis enterprise customer %s\n", c.name)
+	}
+}

Go/DesignPattern/visitor/visitor_test.go

@@ -0,0 +1,31 @@
+/**
+* @Author:zhoutao
+* @Date:2020/12/13 上午10:31
+* @Desc:
+ */
+
+package visitor
+
+func ExampleRequestVisitor() {
+	c := CustomerCol{}
+	c.Add(NewEnterpriseCustomer("NO.1"))
+	c.Add(NewEnterpriseCustomer("NO.2"))
+	c.Add(NewIndividualCustomer("bob"))
+	c.Accept(&ServiceRequestVisitor{})
+	//output :
+	// enterprise
+	// enterprise
+	// individual
+}
+
+func ExampleAnalisis() {
+	c := CustomerCol{}
+	c.Add(NewEnterpriseCustomer("A"))
+	c.Add(NewIndividualCustomer("B"))
+	c.Add(NewEnterpriseCustomer("C"))
+	c.Accept(&AnalisisVisitor{})
+	//output :
+	// enterprise
+	// enterprise
+
+}