Java While循环打印

为什么我的while循环继续打印请输入stock lengthm:

代码：

输出：

Please enter stock length(mm): 4
Please enter quantities of this stock length: 4
Are you done? (y/n): Please enter stock length(mm): 

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使用sc.nextLine代替sc.nextLine

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问题仍然存在=/@Liondancer请参见上文，如果它进入if块并检查done的值。嗯，它不会进入块在进入循环之前检查done的值。即使输入y或yes，也只会输入空格

Please enter stock length(mm): 4
Please enter quantities of this stock length: 4
Are you done? (y/n): Please enter stock length(mm): 

String done = sc.next();
if (done.equalsIgnoreCase("y") || done.equalsIgnoreCase("yes")) {
     System.out.println("breaking out of loop " + "Value of done: " + done)
     break;
}