Golang工厂模式实现与对象创建方法

type Logger interface {
    Log(message string)
}

type ConsoleLogger struct{}

func (c *ConsoleLogger) Log(message string) {
    fmt.Println("[CONSOLE]", message)
}

type FileLogger struct {
    filename string
}

func (f *FileLogger) Log(message string) {
    fmt.Printf("[FILE %s] %s\n", f.filename, message)
}

type LoggerFactory func() Logger

var (
    ConsoleLoggerFactory LoggerFactory = func() Logger { return &ConsoleLogger{} }
    FileLoggerFactory    LoggerFactory = func(filename string) Logger {
        return &FileLogger{filename: filename}
    }
)

func NewFileLoggerFactory(filename string) LoggerFactory {
    return func() Logger {
        return &FileLogger{filename: filename}
    }
}

func NewNetworkLoggerFactory(addr string) LoggerFactory {
    return func() Logger {
        return &NetworkLogger{addr: addr}
    }
}

func RunWithLogger(factory LoggerFactory) {
    logger := factory() // 调用工厂方法，得到具体实例
    logger.Log("Application started")
}

// 使用示例
RunWithLogger(ConsoleLoggerFactory)
RunWithLogger(NewFileLoggerFactory("app.log"))
RunWithLogger(NewNetworkLoggerFactory("127.0.0.1:9000"))

var logFactories = map[string]LoggerFactory{
    "console": ConsoleLoggerFactory,
    "file":    NewFileLoggerFactory("log.txt"),
    "network": NewNetworkLoggerFactory("logs.example.com:8080"),
}

func CreateLogger(kind string) (Logger, error) {
    factory, ok := logFactories[kind]
    if !ok {
        return nil, fmt.Errorf("unknown logger type: %s", kind)
    }
    return factory(), nil
}