how to clear input buffer in java

问题

For avoiding any unwanted character which has been entered in console like \n

we use nextInt() or nextLine() etc.

But in these cases actually the control is going a step ahead leaving the unwanted string or something like this. But I want to delete or flush out the memory of buffer in which other unwanted data is taken by the system. For example -->

Scanner scan=new Scanner(System.in);
scan.nextInt();
scan.nextline();//this statement will be skipped

because the system is taking \n as a line next to the integer given as input. In this case without using scan.nextLine() I want to simply clear/flush out the buffer memory where the \n was stored. Now please tell me how to delete the input buffer memory in java

Thank you. :)

回答1:

You can use this to clear all existing data in the buffer:

while(sc.hasNext()) {
    sc.next();
}

If you are only doing this to remove the newline (\n) characters from the input, you can use:

while(sc.hasNext("\n")) {
    sc.next();
}

If the goal is to only read integers and skip any other characters, this would work:

while(sc.hasNext() && !sc.hasNextInt()) {
    sc.next();
}

来源：https://stackoverflow.com/questions/30985691/how-to-clear-input-buffer-in-java