我对显示数组方法有疑问。我不知道如何使它格式化：
Credit Card # 4:
8908 9014 8812 1331
我需要做的是为每个数组元素调用 display 方法并在标签的字符串中传递数组的索引，我只是不知道该怎么做，我试过了，但它是错误的：
System.out.println(display("Credit Card # %d", cred1[i]));
谁能建议一种方法来做到这一点？
package homework4;
import java.util.Scanner;
public class Prog4 {
static Scanner scanner = new Scanner(System.in);
public static void main(String[] args)
{ CreditCardNumber[] cred1;
CreditCardNumber cred2 = getInput();
Display("The complete number from your input:", cred2);
cred1 = getInputArray();
DisplayArray(cred1);
TryAnother();
}
public static CreditCardNumber getInput() {
String ID;
String accNum;
CreditCardNumber tempCred;
System.out.printf("Please enter issuer ID:");
ID = scanner.next();
System.out.printf("Please enter account number:");
accNum = scanner.next();
tempCred = new CreditCardNumber(ID, accNum);
return tempCred;
}
public static void Display(String ch, CreditCardNumber cred2)
{
System.out.println(ch);
System.out.println(cred2.toString().replaceAll(".{4}", "$0 "));
}
public static CreditCardNumber[] getInputArray()
{
CreditCardNumber[] tempArray;
String tempID;
int size;
System.out.printf("Please enter size of the aray:");
size = scanner.nextInt();
if(size < 1)
{
size = 1;
}
tempArray = new CreditCardNumber[size];
System.out.printf("Please enter issuer ID:");
tempID = scanner.next();
System.out.print(tempArray.length);
for(int i = 0; i < tempArray.length; i++)
{
tempArray[i] = new CreditCardNumber();
tempArray[i].CreateCred(tempID);
}
return tempArray;
}
public static void DisplayArray(CreditCardNumber[] cred1)
{
for(int i = 0; i< cred1.length; i++)
{
System.out.println(display("Credit Card # %d", cred1[i]));
}
}
public static boolean TryAnother()
{
String s;
System.out.printf("Get more credit card numbers? (n for no):");
s = scanner.next();
if(s.charAt(0) != 'N' && s.charAt(0) != 'n')
{
return true;
}
return false;
}
}