Golang exception handling mechanism Panic-defer-recover

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What is the mechanism used for exception processing in go?

A sentence summary:

You can throw an panic exception in go and then catch the exception through recover in defer and then handle it normally.

package mainimport "fmt"func main() {    defer func() { // 必须要先声明defer，否则不能捕获到panic异常        fmt.Println("1")        if err := recover(); err != nil {            fmt.Println(err) // 这里的err其实就是panic传入的内容，the program is crashed        }        fmt.Println("2")    }()    ftest()    f()}func f() {    fmt.Println("b")    panic("the program is crashed")    fmt.Println("c")}func ftest() {    defer fmt.Println("AA")    defer fmt.Println("BB")    fmt.Println("CC")    return    fmt.Println("DD")}

You may be the first time I have the following questions in my mind:

• when does Q1:defer execute?
• Q2: In What order are multiple defer keywords in the program executed?
• After the Q3:recover recovery, will the program * return to the place where the exception occurred and continue to run downwards?

Shall we answer one by one according to the result of execution?

CCBBAAb1the program is crashed2

A1: CC After printing the program return, and then printing BB , indicating that the function returned before the execution of the defer statement, do not print DD , stating that defer must be written before the program return before the Add execution before returning
A2: Print BB after printing AA , stating that defer execution order is declared after the first execution
A3: The program does not print c , stating that the program after recover recovery * will not return to the place where the exception occurred continue to run downwards

Reference:
Http://www.cnblogs.com/ghj1976/archive/2013/02/11/2910114.html