我创建了一个示例,其中我同时运行函数,在其中我恐慌并恢复:
package main
import "fmt"
func main() {
// "main" recovery
defer func() {
if r := recover(); r != nil {
fmt.Println("main goroutine paniced:", r)
}
}()
// running function concurrently inside which I panic
chanStr := make(chan string)
go func() {
// this "internal" goroutin recovery
defer func() {
if r := recover(); r != nil {
fmt.Println("internal goroutine paniced:", r)
}
chanStr <- "hello world"
}()
// panicking and wanting recovery not only in "internal" recovery but in "main" recovery as well
panic("NOT main goroutine")
}()
// waiting for chan with "internal" goroutine panicking and recovery
str := <-chanStr
fmt.Println(str)
// panic("main")
}
它提供输出:
internal goroutine panicked: NOT main goroutine
hello world
是否可以更改我的代码以从&#34;内部&#34;到&#34;主要&#34;?换句话说,我希望它写下来到控制台:
internal goroutine paniced: NOT main goroutine
main goroutine paniced: main
hello world
我试图通过删除&#34;内部&#34;来实现这一点。恢复功能,但&#34;主要&#34;恢复不会恢复内部恐慌&#34;内部&#34;在这种情况下goroutine。
我试图关注@ Momer的建议并通过频道发送错误并在主要的goroutine中处理它,而不是试图让恐慌起来:
package main
import (
"errors"
"fmt"
)
func main() {
// "main" recovery
defer func() {
if r := recover(); r != nil {
fmt.Println("main goroutine paniced:", r)
}
}()
// running func concarantly inside which I panic
chanStr := make(chan string)
chanErr := make(chan error)
var err error
go func() {
// this "internal" goroutin recovery
defer func() {
if r := recover(); r != nil {
fmt.Println("internal goroutine paniced:", r)
switch t := r.(type) {
case string:
fmt.Println("err is string")
err = errors.New(t)
case error:
fmt.Println("err is error")
err = t
default:
fmt.Println("err is unknown")
err = errors.New("Unknown error")
}
chanErr <- err
chanStr <- ""
}
}()
// panicing and wanting recovery not only in "internal" recovery but in "main" recovery as well
panic("NOT main goroutine")
chanStr <- "hello world"
chanErr <- nil
}()
// waiting for chan with "internal" goroutin panicing and recovery
str := <-chanStr
err = <-chanErr
fmt.Println(str)
fmt.Println(err)
// panic("main")
}
它给出了错误
all goroutines are asleep - deadlock
完整输出:
go run /goPath/parentRecoverty2.go
internal goroutine paniced: NOT main goroutine
err is string
fatal error: all goroutines are asleep - deadlock!
goroutine 1 [chan receive]:
main.main()
/goPath/parentRecoverty2.go:48 +0x1d4
goroutine 5 [chan send]:
main.func·002()
/goPath/parentRecoverty2.go:37 +0x407
main.func·003()
/goPath/parentRecoverty2.go:42 +0x130
created by main.main
/goPath/parentRecoverty2.go:46 +0x190
exit status 2
答案 0 :(得分:1)
在您更新的问题中,通过写入chanStr
来阻止一个线程,同时通过写入chanErr
阻止另一个线程被阻止。
切换写入顺序应解决死锁问题。
defer func() {
if r := recover(); r != nil {
fmt.Println("internal goroutine paniced:", r)
switch t := r.(type) {
case string:
fmt.Println("err is string")
err = errors.New(t)
case error:
fmt.Println("err is error")
err = t
default:
fmt.Println("err is unknown")
err = errors.New("Unknown error")
}
chanStr <- ""
chanErr <- err
}
}
答案 1 :(得分:1)
我把golang中的恐慌/恢复作为java或c ++中的try / catch / final块。
有关详细信息,请访问Handling panics (from Golang spec)。
所以你可以将恐慌传递给方法的来电者。 下面是一个简单的代码,希望有所帮助
注意:在函数Foo()中,我使用recover()来捕获出错的东西,然后重新发生混乱,以便稍后在外部调用者中捕获它。
package main
import (
"fmt"
"time"
)
func Foo() {
defer func() {
if x := recover(); x != nil {
fmt.Printf("Runtime panic: %v \n", x)
panic("Ah oh ... Panic in defer")
}
}()
panic("Panic in Foo() !")
}
func Game() {
defer func(){
fmt.Println("Clean up in Game()")
}()
defer func() {
if x := recover(); x != nil {
fmt.Println("Catch recover panic !!! In Game()")
}
}()
Foo()
}
func main() {
defer func() {
fmt.Println("Program Quit ... ")
}()
fmt.Println("-----------Split-------------")
go Game()
time.Sleep(1 * time.Millisecond)
fmt.Println("-----------Split-------------")
}