I tried to do an input check (need to take 3 numbers using Scanner).
Before that, I used a similar method (.hasNext(int)
) in another task - everything worked fine. In this case, it doesn't work.
The first "while" loop works correctly, on the second loop .hasNextInt()
returns false and loops the loop - not giving the opportunity to enter data.
boolean num1IsInt = false;
boolean num2IsInt = false;
boolean num3IsInt = false;
int scaicius1 = 0;
int scaicius2 = 0;
int scaicius3 = 0;
System.out.println("Įveskite 3 skaičiai, po viena after each press enter");
while (!num1IsInt) { //check first number is int
Scanner sc1 = new Scanner(System.in);
System.out.println("(1)Įveskyte pirmas skaicius");
if (sc1.hasNextInt()) {
scaicius1 = sc1.nextInt();
num1IsInt = true;
} else {
System.out.println("Not correct integer");
continue;
}
sc1.close();
}
while (!num2IsInt) { //check second number is int
Scanner sc2 = new Scanner(System.in);
System.out.println("(2)Įveskyte antras skaicius");
if (sc2.hasNextInt()) {
scaicius2 = sc2.nextInt();
num2IsInt = true;
} else {
System.out.println("Not correct integer");
continue;
}
sc2.close();
}
while (!num3IsInt) { //check third number is int
Scanner sc3 = new Scanner(System.in);
System.out.println("(3)Įveskyte trecias skaicius");
if (sc3.hasNextInt()) {
scaicius3 = sc3.nextInt();
num3IsInt = true;
sc3.close();
} else {
System.out.println("Not correct integer");
continue;
}
sc3.close();
}
System.out.println("First number = " + scaicius1);
System.out.println("First number = " + scaicius2);
System.out.println("First number = " + scaicius3);
Thank you - @Thomas Kläger. I change code like was at the begin (with only one Scanner, cose with 3 scanners it's didn't work) and add to all else statements reader for this "ghost element which loop my code".
boolean num1IsInt = false;
boolean num2IsInt = false;
boolean num3IsInt = false;
int scaicius1 = 0;
int scaicius2 = 0;
int scaicius3 = 0;
System.out.println("Įveskite 3 skaičiai, po viena after each press enter");
**Scanner sc = new Scanner(System.in);**
while (!num1IsInt) { //check first number is int
System.out.println("(1)Įveskyte pirmas skaicius");
if (sc.hasNextInt()) {
scaicius1 = sc.nextInt();
num1IsInt = true;
} else {
System.out.println("Not correct integer");
**sc.next();**
}
}
while (!num2IsInt) { //check second number is int
System.out.println("(2)Įveskyte antras skaicius");
if (sc.hasNextInt()) {
scaicius2 = sc.nextInt();
num2IsInt = true;
} else {
System.out.println("Not correct integer");
sc.next();
}
}
while (!num3IsInt) { //check third number is int
System.out.println("(3)Įveskyte trecias skaicius");
if (sc.hasNextInt()) {
scaicius3 = sc.nextInt();
num3IsInt = true;
} else {
System.out.println("Not correct integer");
sc.next();
}
}
sc.close();
System.out.println("First number = " + scaicius1);
System.out.println("First number = " + scaicius2);
System.out.println("First number = " + scaicius3);