Go 的并发 Java 示例

Question

我有以下来自GoByExamples的并发通道示例Java中是否有等价的东西？我原以为实现同样的事情会更加冗长。// Basic sends and receives on channels are blocking.// However, we can use `select` with a `default` clause to// implement _non-blocking_ sends, receives, and even// non-blocking multi-way `select`s.package mainimport "fmt"func main() {    messages := make(chan string)    signals := make(chan bool)    // Here's a non-blocking receive. If a value is    // available on `messages` then `select` will take    // the `<-messages` `case` with that value. If not    // it will immediately take the `default` case.    select {    case msg := <-messages:        fmt.Println("received message", msg)    default:        fmt.Println("no message received")    }    // A non-blocking send works similarly.    msg := "hi"    select {    case messages <- msg:        fmt.Println("sent message", msg)    default:        fmt.Println("no message sent")    }    // We can use multiple `case`s above the `default`    // clause to implement a multi-way non-blocking    // select. Here we attempt non-blocking receives    // on both `messages` and `signals`.    select {    case msg := <-messages:        fmt.Println("received message", msg)    case sig := <-signals:        fmt.Println("received signal", sig)    default:        fmt.Println("no activity")    }}

Answer 1

Select语句是在 Go 语言语法级别引入并发的原因。并发函数调用可以（并且通常完成）在库级别使用辅助函数spawn( function())和通道实现，就像大多数其他语言中具有互斥锁或锁的数据结构一样。但select声明不能。