有没有任何好的+免费+轻量级+ Linux UML设计工具？(Are there any good + free + Lightweight+ Linux UML Design tools? [closed])

 我确信你的缓冲区中有一个额外的未消耗的新行字符。 通过在else-if之后在while循环的末尾添加一行来消费它 
 
   else if(searchagain=='y')
        {
            runnable=true;
        }    
   br.nextLine();
 
 键入第一个输入后按Enter键， Scanner.nextLine()此扫描器超过当前行并返回跳过的输入。 此方法返回当前行的其余部分，不包括末尾的任何行分隔符。 因此，行分隔符\n仍然在缓冲区中，这是在第二次迭代循环时消耗的。我们需要通过调用br.nextLine();来有目的地使用它br.nextLine(); 在while循环结束时，将新行字符\n留在空中，然后进行第二次循环以获得新输入。 这将使其停止并第二次获得输入。 
 
 让我以简单的方式解释你。 你的程序要求 
 
 
 
 输入您希望搜索的图书 
 
 
 现在，您给出Effective Java并按Enter键。 这会变成 
 
 
 
 EffectiveJava \ n 
 
 
 输入结尾的\n （未消耗的char）将不会被br.nextLine() 。 因此，我们需要在while循环结束时明确地删除它。 所以，在第二个循环期间， \n将不会被br.nextLine() ，它将要求您输入 

I am sure that you have an extra unconsumed new line character in your buffer. Consume it by adding a line at the end of the while loop after else-if
 
   else if(searchagain=='y')
        {
            runnable=true;
        }    
   br.nextLine();
 
When you hit enter after keying the first input, Scanner.nextLine() advances this scanner past the current line and returns the input that was skipped. This method returns the rest of the current line, excluding any line separator at the end. so, the line seperator \n is still in the buffer, which is been consumed while iterating the loop for the second time.we need to consume it purposefully by invoking br.nextLine(); at the end of the while loop and leave the new line character \n in air and go for second loop for fresh input. This will make it to stop and get the input for the second time.
 
Let me explain you in a simple way. Your program asks for
 
 
 
Input Books you wish for search
 
 
Now, you give Effective Java and press enter. This would become
 
 
 
EffectiveJava\n
 
 
\n (unconsumed char) in the end of your input will not be consumed by br.nextLine(). So, we need to explicitly get rid of it at the end of while loop. so, that \n will not be consumed by the br.nextLine() during the second loop and it will ask for your input