小编Mei*_*orn的帖子

我用最少的配置安装了CentOS 7(os + dev工具).我正在尝试打开80端口进行httpd服务,但是我的iptables服务有问题......它出了什么问题？我究竟做错了什么？

# ifconfig/sbin/service iptables save
bash: ifconfig/sbin/service: No such file or directory


# /sbin/service iptables save
The service command supports only basic LSB actions (start, stop, restart, try-restart, reload, force-reload, status). For other actions, please try to use systemctl.

# sudo service iptables status
Redirecting to /bin/systemctl status  iptables.service
iptables.service
   Loaded: not-found (Reason: No such file or directory)
   Active: inactive (dead)

# /sbin/service iptables save
The service command supports only basic LSB actions (start, stop, …

请描述这n| = n >>> x5条线的作用？

我对什么|或>>>运营商不感兴趣.我对数学语言中隐藏的复杂逻辑感兴趣.

/**
 * Returns a power of two size for the given target capacity.
 */
static final int tableSizeFor(int cap) {
    int n = cap - 1;
    n |= n >>> 1;
    n |= n >>> 2;
    n |= n >>> 4;
    n |= n >>> 8;
    n |= n >>> 16;
    return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
}

我在浏览器日志中遇到以下异常:

警报上未找到指令注释

堆栈跟踪:

Error: No Directive annotation found on Alert
at new BaseException (webpack:///./~/angular2/src/facade/exceptions.js?:15:23)
at DirectiveResolver.resolve (webpack:///./~/angular2/src/core/linker/directive_resolver.js?:41:15)
at RuntimeMetadataResolver.getDirectiveMetadata (webpack:///./~/angular2/src/compiler/runtime_metadata.js?:41:51)
at eval (webpack:///./~/angular2/src/compiler/runtime_metadata.js?:98:62)
at Array.map (native)
at Array.map (webpack:///./~/es6-shim/es6-shim.js?:1113:14)
at RuntimeMetadataResolver.getViewDirectivesMetadata (webpack:///./~/angular2/src/compiler/runtime_metadata.js?:98:27)
at TemplateCompiler._compileNestedComponentRuntime (webpack:///./~/angular2/src/compiler/template_compiler.js?:151:65)
at eval (webpack:///./~/angular2/src/compiler/template_compiler.js?:136:87)
at Array.forEach (native)
at Array.forEach (webpack:///./~/es6-shim/es6-shim.js?:1107:14)
at eval (webpack:///./~/angular2/src/compiler/template_compiler.js?:136:43)
at Zone.run (webpack:///./~/zone.js/dist/zone-microtask.js?:1216:24)
at Zone.eval [as run] (webpack:///./~/angular2/src/core/zone/ng_zone.js?:344:42)
at zoneBoundFn (webpack:///./~/zone.js/dist/zone-microtask.js?:1193:26)
at lib$es6$promise$$internal$$tryCatch (webpack:///./~/zone.js/dist/zone-microtask.js?:441:17)
at lib$es6$promise$$internal$$invokeCallback (webpack:///./~/zone.js/dist/zone-microtask.js?:453:18)
at lib$es6$promise$$internal$$publish (webpack:///./~/zone.js/dist/zone-microtask.js?:424:12)
at eval (webpack:///./~/zone.js/dist/zone-microtask.js?:96:10)
at microtask (webpack:///./~/angular2/src/core/zone/ng_zone.js?:384:29)
at Zone.run (webpack:///./~/zone.js/dist/zone-microtask.js?:1216:24)
at Zone.eval [as run] …