More help on java modifications

[Troy Johnson]

Hello. Thanks for everyones assistance on this problem. Again, I am working on making two modifications to the program. The first is to Ignore cases, which I have successfully completed. The second is to Use a command-line argument. I have utilized suggestions on using the command-line argument into the program and have implemented them into my program. My program compiles, but I get the following error message when I run the application: Exception in thread "main" java.lang.NoSuchMethodError: main. Could anyone offer any more suggestions or insight on this. Thanks.
Here is my code before using the command-line argument:

public class Palindrome {
  public static void main(String[] args) {
    // Prompt the user to enter a string
     String s = JOptionPane.showInputDialog(
              null, "Enter a string:",
      " Input", JOptionPane.QUESTION_MESSAGE);

    if (isPalindrome(s)) {
      System.out.println(s + " is a palindrome");
    }
    else {
      System.out.println(s + " is not a palindrome");
    }
}

  /** Check if a string is a palindrome */
  public static boolean isPalindrome(String s) {
    // The index of the first character in the string
    int low = 0;

    // The index of the last character in the string
    int high = s.length() - 1;

    while (low < high) {
      if (!equals(s.charAt(low), s.charAt(high)))
        return false; // Not a palindrome

      low++;
      high--;
    }

    return true; // The string is a palindrome
  }

  /** Return true if two letters are the same regardless case */
  public static boolean equals(char c1, char c2) {
    return lowercase(c1) == lowercase(c2);
  }

  public static char lowercase(char c) {
    if (c >= 'A' && c <= 'Z') {
      int offset = (int)'a' - (int)'A';
      char lowercase = (char)((int)c + offset);
      return lowercase;
    }
    else
      return c;
  }
}

Here is my code after using a command-line argument, which I get the NoSuchError method when trying to run the application.

class Palindrome
{
public  Palindrome(String word)
{
System.out.println(word + " = "+ isPalindrome(word)+", as a palindrome");
}
private boolean isPalindrome(String s)
{
s = s.toLowerCase();
for(int i = 0; i < s.length()/2; i++)
{
if(s.charAt(i) != s.charAt(s.length()-1-i)) return false;
}
return true;
}
public static void main(String[] args)
{
new Palindrome(args[0]);
  }
}

 public class problem {
  /** Check if a string is a palindrome */
  public static boolean isPalindrome(String s) {
    // The index of the first character in the string
    int low = 0;
    // The index of the last character in the string
    int high = s.length() - 1;
    while (low < high) {
      if (!equals(s.charAt(low), s.charAt(high)))
        return false; // Not a palindrome
      low++;
      high--;
    }
    return true; // The string is a palindrome
  }
  /** Return true if two letters are the same regardless case */
  public static boolean equals(char c1, char c2) {
    return lowercase(c1) == lowercase(c2);
  }
  public static char lowercase(char c) {
    if (c >= 'A' && c <= 'Z') {
      int offset = (int)'a' - (int)'A';
      char lowercase = (char)((int)c + offset);
      return lowercase;
    }
    else
      return c;
  }
}

[ October 12, 2003: Message edited by: Troy Johnson ]
[ October 12, 2003: Message edited by: Troy Johnson ]

[Ernest Friedman-Hill]

Only the "Palindrome" class has a main(), so you can only run that class -i.e., "java Palindrome". If you try to run "problem" you'll get this error. (Not sure what the other class is for, actually.)

[Wirianto Djunaidi]

Actually the second code does not compile, because the main() method is in Palindrome class and it was declared with default access modifier. Instead you have your problem class declared as coderanch.
You should declare your Palindrom class as public instead of problem.

[Michael Dunn]

You only need that part of code I posted in your other thread, and run it with an argument

[Troy Johnson]

Michael, thanks for your help. I guess I am still a little unclear on running an argument to that code? Thanks.