I have a set of double values, and they can be retrieved by calling the method getArrivalTime()
which belongs to the Customer class. When I run through this while loop, I am unable to print out my output as I cannot exit the loop.
while (sc.hasNextLine()) {
Customer customer = new Customer(sc.nextDouble());
String timeToString = String.valueOf(customer.getArrivalTime());
if (!(timeToString.isEmpty())) {
c.add(customer);
} else {
break;
}
}
eg
Inputs:
0.500
0.600
0.700
I have already included a break;
at the end of the loop. What else can do?
You could make this break from the loop on a blank line if you read the input as strings and then parse them into doubles.
while (sc.hasNextLine()) {
String line = sc.nextLine();
if (line.isEmpty()) {
break;
}
c.add(new Customer(Double.parseDouble(line)));
}
Alternatively you could use hasNextDouble()
instead of hasNextLine()
in your existing code. It is an error to mix hasNextLine()
and nextDouble()
.
I guess you are using a Scanner
. You are iterating line by line. So don't call nextDouble
but nextLine
then parse your line as Double.
Here's a simplified version :
import java.util.Scanner;
public class Snippet {
public static void main(String[] args) {
try (Scanner sc = new Scanner("0.500\r\n" + "0.600\r\n" + "0.700");) {
while (sc.hasNextLine()) {
String line = sc.nextLine();
double customer = Double.parseDouble(line);
System.out.println(customer);
}
}
}
}
Otherwise, if your file format matches the double pattern (it depends on your Locale...), you may want to use hasNextDouble
with nextDouble
:
import java.util.Scanner;
public class Snippet { public static void main(String[] args) {
try (Scanner sc = new Scanner("0,500\r\n" + "0,600\r\n" + "0,700");) {
while (sc.hasNextDouble()) {
double customer = sc.nextDouble();
System.out.println(customer);
}
}
}
}
HTH!
If you don't want use goto
like operations you could always add a boolean
flag condition to you while
.
boolean flag = true;
while (sc.hasNextLine() && flag) {
Customer customer = new Customer(sc.nextDouble());
String timeToString = String.valueOf(customer.getArrivalTime());
if (!(timeToString.isEmpty())) {
c.add(customer);
} else {
flag = false;
}
}
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