Zaham2 :
I'm trying to take multi-line user input in Java and split the lines into an array, I need this to solve a problem for an online judge. I'm using a Scanner to take input. I cant determine the end of input. I always get an infinite loop, since I don't know the size of input (i.e number of lines)
Terminating input with an empty String (clicking enter) is still an infinite loop. Code provided below.
public static void main(String[] args) {
ArrayList<String> in = new ArrayList<String>();
Scanner s = new Scanner(System.in);
while (s.hasNextLine() == true){
in.add(s.nextLine());
//infinite loop
}
}
I'm not even sure why the loop executes the first time. I believe the hasNextLine() should be false the first time ,since no input was taken yet. Any help or clarification appreciated.
Coronero :
You could use the empty line as a loop-breaker:
while (s.hasNextLine()){ //no need for "== true"
String read = s.nextLine();
if(read == null || read.isEmpty()){ //if the line is empty
break; //exit the loop
}
in.add(read);
[...]
}
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