<span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">Golang</span>
的优点有很多,以前的文章中也有提到过,但也有很多槽点为Gopher所诟病,尤其是 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">错误处理<code style="white-space-collapse: preserve-breaks; box-sizing: border-box; background: rgb(243, 241, 241); color: rgb(88, 88, 88); line-height: 18px;"><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">错误处理</span>
。在说错误和异常之前,先要说两个概念:
错误处理:错误是业务中的一部分,是可以预见的。
异常处理:非业务的一部分,不可预见的。
错误处理
首先看一下示例代码:
file, err := os.Open("/usr/local/test.txt")
Golang官方推荐上述代码中的错误处理方式,并且建议 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">err<code style="box-sizing: border-box;background: rgb(243, 241, 241);color: rgb(88, 88, 88);line-height: 18px;"><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">err</span>
放在返回值的最后。我们在日常的编码中也需要遵循这样的规则来定义 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">func<code style="box-sizing: border-box;background: rgb(243, 241, 241);color: rgb(88, 88, 88);line-height: 18px;"><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">func</span>
。
在Gopher间流传着这样一个笑话:一半时间在编写代码,一半时间在写错误处理。
示例代码:
func Open(name string) (*File, error) { return OpenFile(name, O_RDONLY, 0) }
但通常不是每个方法都需要处理 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">err</span>
,可以适当的将 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">err</span>
返回给上层函数,由上层函数统一打印或者处理错误。例如:<span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">http</span>
路由中的错误可以在路由返回数据前处理,将错误信息和错误码格式化后返回给 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">Client</span>
。
异常处理
Golang的异常处理比较特立独行,需要 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">defer</span>
<span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">err</span>
<span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">recover</span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">()</span>
三者配合使用 ,而Java只要 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">try</span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">{</span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;"></span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">}</span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">Catch</span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">()</span>
就可以搞定,还是来看一下示例代码:
package main import ( "fmt" ) func main() { test() } func test() { defer func() { if e := recover(); e != nil { fmt.Println("Worng!") } }() panic("panic") }
如上代码在 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">test</span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">()</span>
函数及其子函数中如果发生panic的错误,就会打印:
Worng!
代码封装
当然,在每个方法最上面写这么一大堆冗余的代码是很不优雅的,也不符合面向对象的特性:<span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">封装</span>
,于是便可以封装成 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">CoverErrorMessage</span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">()</span>
,而 <span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">test</span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">()</span>
函数改写如下:
package main import ( "fmt" ) func main() { test() } func test() { defer tools.CoverErrorMessage() panic("panic") } func CoverErrorMessage() { if message := recover(); message != nil { var err error switch x := message.(type) { case string: err = errors.New(x) case error: err = x default: err = errors.New("Unknow panic") } Logger.Error("Recovered panic error : ",err) } }
defer 处理异常时只能将
<span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">recover</span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">()</span>
写在第一层函数中,否则将无法<span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">recover</span><span style="box-sizing: border-box;background-image: initial;background-position: initial;background-size: initial;background-repeat: initial;background-attachment: initial;background-origin: initial;background-clip: initial;display: inline-block;padding-right: 2px;padding-left: 2px;font-size: 14px;">()</span>
到panic错误
以上是Golang的异常处理的详细内容。更多信息请关注PHP中文网其他相关文章!

Golang和Python的主要区别在于并发模型、类型系统、性能和执行速度。1.Golang使用CSP模型,适用于高并发任务;Python依赖多线程和GIL,适合I/O密集型任务。2.Golang是静态类型,Python是动态类型。3.Golang编译型语言执行速度快,Python解释型语言开发速度快。

Golang通常比C 慢,但Golang在并发编程和开发效率上更具优势:1)Golang的垃圾回收和并发模型使其在高并发场景下表现出色;2)C 通过手动内存管理和硬件优化获得更高性能,但开发复杂度较高。

Golang在云计算和DevOps中的应用广泛,其优势在于简单性、高效性和并发编程能力。1)在云计算中,Golang通过goroutine和channel机制高效处理并发请求。2)在DevOps中,Golang的快速编译和跨平台特性使其成为自动化工具的首选。

Golang和C 在执行效率上的表现各有优势。1)Golang通过goroutine和垃圾回收提高效率,但可能引入暂停时间。2)C 通过手动内存管理和优化实现高性能,但开发者需处理内存泄漏等问题。选择时需考虑项目需求和团队技术栈。

Golang更适合高并发任务,而Python在灵活性上更有优势。1.Golang通过goroutine和channel高效处理并发。2.Python依赖threading和asyncio,受GIL影响,但提供多种并发方式。选择应基于具体需求。

Golang和C 在性能上的差异主要体现在内存管理、编译优化和运行时效率等方面。1)Golang的垃圾回收机制方便但可能影响性能,2)C 的手动内存管理和编译器优化在递归计算中表现更为高效。

selectgolangforhighpperformanceandcorrency,ifealforBackendServicesSandNetwork程序; selectpypypythonforrapiddevelopment,dataScience和machinelearningDuetoitsverserverserverserversator versator anderticality andextility andextentensivelibraries。

Golang和Python各有优势:Golang适合高性能和并发编程,Python适用于数据科学和Web开发。 Golang以其并发模型和高效性能着称,Python则以简洁语法和丰富库生态系统着称。


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