所以我得到了一个项目,我必须在那里验证ISBN-10和ISBN-13号码。我的问题是我想根据用户输入的内容使用ArrayList(用户将所需数量添加到ArrayList中)。这是我的代码(没有ArrayList)。如何修改此项以便用户可以根据需要添加多少个ISBN号?
public static void main(String args[]) {
Scanner input = new Scanner(System.in);
String isbn;
//Get the ISBN
System.out.print("Enter an ISBN number ");
isbn = input.nextLine();
input.close();
//Strip out the spaces/System.out.println("Press 1 to enter a list of ISBN numbers to verify. ");System.out.println("Press 1 to enter a list of ISBN numbers to verify. ");dashes by replacing with empty character.
isbn = isbn.replaceAll("( |-)", "");
//Check depending on length.
boolean isValid = false;
if(isbn.length()== 10){
isValid = CheckISBN10(isbn);
}else if (isbn.length()== 13){
isValid = CheckISBN13(isbn);
}else{
isValid = false;
}
//Print check Status
if(isValid){
System.out.println(isbn + " IS a valid ISBN");
}else{
System.out.println(isbn + " IS NOT a valid ISBN");
}
}
//Checking ISBN-10 numbers are valid
//
private static boolean CheckISBN10(String isbn){
int sum = 0;
String dStr;
for (int d = 0; d < 10; d++){
dStr = isbn.substring(d, d + 1);
if (d < 9 || dStr != "X"){
sum += Integer.parseInt(dStr) * (10-d);
}else {
sum += 10;
}
}
return (sum %11 == 10);
}
private static boolean CheckISBN13(String isbn){
int sum = 0;
int dVal;
for (int d = 0; d < 13; d++){
dVal = Integer.parseInt(isbn.substring(d, d + 1));
if (d % 2 == 0){
sum += dVal * 1;
}else {
sum += dVal * 3;
}
}
return (sum % 10 == 0);
}
}
答案 0 :(得分:2)
public static List<String> scanNumberToListUntilAppears(String end) {
if(end == null || end.isEmpty())
end = "end";
List<String> numbers = new ArrayList<>();
String message = "Enter an ISBN number: ";
try (Scanner input = new Scanner(System.in)) {
System.out.print(message);
while(input.hasNext()) {
String isbn = input.nextLine();
if(isbn.equalsIgnoreCase(end)) {
if(!numbers.isEmpty())
break;
} else {
numbers.add(isbn);
if(numbers.size() == 1)
message = "Enter the next ISBN number or '" + end + "': ";
}
System.out.print(message);
}
input.close();
}
return numbers;
}
答案 1 :(得分:1)
while (istr.get() != std::char_traits<char>::eof())
max++;