go語言接口適配，適配器模式

直接上代碼：

package main                                                                   
                                                                               
import "log"                                                                   
                                                                               
type LogIN interface {                                                         
    WARN(string)                                                               
    INFO(string)                                                               
    //其他省略                                                                 
}                                                                              
                                                                               
/*                                                                             
假設你寫了一個框架,框架里需要打日志，具體是個什么樣的日志由使用者決定          
*/                                                                             
type Frame struct {                                                            
    name string                                                                
    log  LogIN                                                                 
}                                                                              
                                                                               
func (f *Frame) Start() {                                                      
    f.log.INFO("frame start...")                                               
}                                                                              
                                                                               
//但是問題來了，使用者用了一個這樣的日志庫                                     
                                                                               
type RealLog struct {                                                          
}                                                                              
                                                                               
func (l *RealLog) warn(s string) {                                             
    log.Print(s)                                                               
}                                                                              
                                                                               
func (l *RealLog) info(s string) {                                             
    log.Print(s)                                                               
}                                                                              
                                                                               
//可以看到，真正使用的日志與框架定義的日志接口不一樣，如此我們就需要適配       
                                                                               
type AdaptLog struct {                                                         
    rellog *RealLog                                                            
}                                                                              
                                                          
func (alog *AdaptLog) WARN(s string) {                                         
    alog.rellog.warn(s)                                                        
}

func (alog *AdaptLog) INFO(s string) {
    alog.rellog.info(s)
}

//有了這個適配器，我們就可以很好的在框架里使用RealLog了

func main() {
    adaptlog := AdaptLog{&RealLog{}}
    frame := Frame{name: "frame", log: &adaptlog}

    frame.Start()
}