Check Palindrome()

Step 1: Understand the problem

Before we write any code, we first need to understand what a palindrome is. A palindrome is a word, number, phrase, or other sequence of characters that reads the same forward and backwards, ignoring spaces, punctuation, and capitalization. "Anna", "racecar", and "Able was I ere I saw Elba" are all examples of palindromes.

So, our task is to write a function in Java that takes a string and returns true if it's a palindrome and false otherwise.

public boolean isPalindrome(String str) {
    // Implementation will go here.
}

Step 2: Approach to solve the problem

We know that a palindrome reads the same forward and backwards. One approach to check if a string is a palindrome is to reverse the string and compare it with the original string. If they are the same, the string is a palindrome.

Step 3: Reverse the string

In Java, we can use a StringBuilder to reverse a string. Here's how you do it:

public boolean isPalindrome(String str) {
    String reversed = new StringBuilder(str).reverse().toString();
    // Comparison will go here.
}

Step 4: Compare the reversed string with the original

Now that we have the reversed string, we can compare it with the original string.

public boolean isPalindrome(String str) {
    String reversed = new StringBuilder(str).reverse().toString();
    return str.equals(reversed);
}

Step 5: Making the function case-insensitive

There's one final step. Our function is currently case-sensitive, but we want it to ignore case. To solve this, we can convert both the original and reversed strings to lower case before comparing them.

Here's our final code:

public boolean isPalindrome(String str) {
    String lowerCaseStr = str.toLowerCase();
    String reversed = new StringBuilder(lowerCaseStr).reverse().toString();
    return lowerCaseStr.equals(reversed);
}

Conclusion

And there you have it, a function that checks if a string is a palindrome. This function works by reversing the string and comparing it with the original, case-insensitive string. This is one of many ways to solve this problem, and showcases the power and flexibility of computer programming.