Java Programming

Hello Everyone,

I am tackling an algorithmic problem trying to find the longest palindrome inside of a text file. As of right now, I know how to determine if a word is or is not a palindrome. However, the issue that I am having at the moment is trying to come up with an efficient algorithm that can solve this in the fastest way possible. Please help give ideas/suggestions on an algorithm that I should follow to achieve this.

So for example, lets say we have a text file that has 10,000 characters. One of the things that I have concluded is that in order to determine if a word is a palindrome, you must be able to know the first and last characters. Right now, the only thing that I can think of is to:

for( start with the first character x,  until the last character 10,0000)
{
          int Y = index 10,000
          while( X < Y )
          {
                if(the substring from X to the last character Y is not a palindrome)
                 {
                Y = Y - 1;
                }
                else
                {
                         currentLongestPalindrome = substring from X to Y;
                         BREAK;
                }
          }
}

Sorry everyone for the incorrect Java syntax, but that is the basic idea that I have come up with. This looks terrible as it is taking over an hour to be able to run this solution. Do you guys have any suggestions?

Thanks in advance.