我遇到的问题是我无法让我的密码验证程序来检查字符串，以确保其中的一个字符为大写字母，而一个字符为小写字母，它将检查整个字符串中是否存在一个字符。其他，并根据要检查的语句打印错误消息。
我已经查看了该站点和Internet上的答案，但是找不到。这是功课。
下面是我当前的代码。
import java.util.Scanner;
public class password
{
public static void main(String[] args)
{
Scanner stdIn = new Scanner(System.in);
String password;
String cont = "y";
char ch;
boolean upper = false;
boolean lower = false;
System.out.println("Setting up your password is easy. To view requirements enter Help.");
System.out.print("Enter password or help: ");
password = stdIn.next();
ch = password.charAt(0);
while (cont.equalsIgnoreCase("y"))
{
while (password.isEmpty())
{
System.out.print("Enter password or help: ");
password = stdIn.next();
}
if (password.equalsIgnoreCase("help"))
{
System.out.println("Password must meet these requirements." +
"\nMust contain 8 characters.\nMust contain 1 lower case letter." +
"\nMust contain 1 upper case letter.\nMust contain 1 numeric digit." +
"\nMust contain 1 special character !@#$%^&*\nDoes not contain the word AND or NOT.");
password = "";
}
else if (password.length() < 8)
{
System.out.println("Invalid password - Must contain 8 charaters.");
password = "";
}
else if (!(Character.isLowerCase(ch)))
{
for (int i=1; i
{
ch = password.charAt(i);
if (!Character.isLowerCase(ch))
{
System.out.println("Invalid password - Must have a Lower Case character.");
password = "";
}
}
}
else if (!(Character.isUpperCase(ch)))
{
for (int i=0; i
{
ch = password.charAt(i);
if (!Character.isUpperCase(ch))
{
System.out.println("Invalid password - Must have an Upper Case character.");
password = "";
}
}
}
else
{
System.out.println("Your password is " + password);
System.out.print("Would you like to change your password? Y/N: ");
cont = stdIn.next();
password = "";
}
while (!cont.equalsIgnoreCase("y") && !cont.equalsIgnoreCase("n"))
{
System.out.print("Invalid Answer. Please enter Y or N: ");
cont = stdIn.next();
}
}
}
}
