Java Palindrome Help

[Kruse]

Basically, I want a method to check if a given string sequence is a palindrome or not, however disregarding the existence of whiespaces, commas, and apostrophes. Also, we cannot find the reverse of a string then compare it to the original; the method we are using is checking/comparing the first and last character then incrementing/decrementing and again comparing.

The method I came up with is:

public static boolean isPalindromePhrase(String str)
    {
        if (str.length() <= 1) // a one-character string is always a palindrome
            return true;
            
        char rightChars, leftChars;
        int first = 0;
        int last = str.length() - 1;
        
        while (first < last)
        {
            leftChars = str.charAt(first); // characters from the left (moving from left to right)
            leftChars = Character.toLowerCase(leftChars); 
            rightChars = str.charAt(last); // characters from the left (moving from right to left)
            rightChars = Character.toLowerCase(rightChars);
            
            if (leftChars == ' ' || leftChars == '\'' || leftChars == ',')
            {
                leftChars = str.charAt(first++);
            }
            if (rightChars == ' ' || rightChars == '\'' || rightChars == ',')
            {
                rightChars = str.charAt(last--);
            }
            
            if (leftChars == rightChars)
            {
                first++;
                last--;
            }
            else
                return false;
        }
        return true;
    }

Logically, this seems okay, but a string such as "Madam, I'm Adam" is not working. Technically, it is not a true palindrome, but again I was the program to disregard spaces, commas, and apostrophes. The assignment is due for tomorrow, and this is the only problem I have yet. I tried asking programming forums, but they all were misleading/complicated to fathom considering I am still an amateur in java.

Any help is appreciated, if any.

*please move to its suitable subforum if not right here.

 

[SpeedyGeek]

Why don't you just make two methods? One that removes all the crap you don't need and one that checks for the palindrome?

 

[Archer]

At a quick glance, you're only doing a single test on whether the given side has an illegal character and incrementing/decrementing respectively. So if you have two ore more adjacent characters, such as a comma and a space, then you are only checking for the first one. Shouldn't they be while loops, instead?

But SpeedyGeek is correct. If you can create a function to trim the string down and another to check palendomicy, that would be much neater. Even if you just nest one inside the other so the variable stays as-is outside of the scope of these two functions.