问题描述
我想在控制台上执行后打印地图"的每一步.
I want to print each step of my "map" after its execution on the console.
有点像
System.out.println("完成第一步");System.out.println("完成第二步");
System.out.println("Completed Step one");System.out.println("Completed Step two");
等等
是否有一个特殊的命令可以做到这一点,或者根本不可能,因为 System.out.println 似乎根本不起作用?
Is there a special command to do that or is it not possible at all, as System.out.println doesn't seem to work at all ?
请指导
推荐答案
您可以使用 System.out.println(..
.要查看打印的内容,请打开 jobtracker Web 控制台.然后导航到您提交的作业的链接.在作业页面上,您将看到指向所有单独的 Map/Reduce 任务的链接.点击这些链接.. 您将找到一个链接,该链接显示标准输出以及标准错误的转储.
You can use System.out.println(..
. To see whats been printed, open the jobtracker web console. Then navigate to your submitted job's link. On the Job page, you will see links to all your individual Map/Reduce tasks. Follow the links.. you will find a link that displays the dump of both the Standard output as well as the Standard error.
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