Java isLetterOrDigit()方法,isDigit(),isLetter()

Question

我试图找出如何检查a String以验证它是否至少有一个字母和一个数字.我会提前说这是家庭作业,我有点困惑.

有一种方法isLetterOrDigit()方法似乎是正确的方法,但我不如我将如何在我的代码中实现它.这是我在下面使用的代码:

import javax.swing.JOptionPane;

public class Password
{
    public static void main(String[] args)
    {

    String initialPassword;
    String secondaryPassword;
    int initialLength;

    initialPassword = JOptionPane.showInputDialog(null, "Enter Your Passowrd.");

    initialLength = initialPassword.length();

    JOptionPane.showMessageDialog(null, "initialLength = " + initialLength);

    while (initialLength < 6 || initialLength > 10)
    {
        initialPassword = JOptionPane.showInputDialog(null, "Your password does not meet the length requirements. It must be at least 6 characters long but no longer than 10.");
        initialLength = initialPassword.length();
    }

    //Needs to contain at least one letter and one digit

    secondaryPassword = JOptionPane.showInputDialog(null, "Please enter your password again to verify.");

    JOptionPane.showMessageDialog(null, "Initial password : " + initialPassword + "\nSecondar Password : " + secondaryPassword);

    while (!secondaryPassword.equals(initialPassword))
    {
        secondaryPassword = JOptionPane.showInputDialog(null, "Your passwords do not match. Please enter you password again."); 
    }

    JOptionPane.showMessageDialog(null, "The program has successfully completed."); 

    }
}

我想实现在注释部分则会使用的方法isDigit(),isLetter()或isLetterOrDigit()方法,但我只是不知道如何做到这一点.

任何指导将不胜感激.在此先感谢您的帮助.

Answer 1

这应该工作.

public boolean containsBothNumbersAndLetters(String password) {
  boolean digitFound = false;
  boolean letterFound = false;
  for (char ch : password.toCharArray()) {
    if (Character.isDigit(ch)) {
      digitFound = true;
    }
    if (Character.isLetter(ch)) {
      letterFound = true;
    }
    if (digitFound && letterFound) {
      // as soon as we got both a digit and a letter return true
      return true;
    }
  }
  // if not true after passing through the entire string, return false
  return false;
}