How can I eliminate duplicate words from String in Java?

Question

I have an ArrayList of Strings and it contains records such as:

this is a first sentence
hello my name is Chris 
what's up man what's up man
today is tuesday

I need to clear this list, so that the output does not contain repeated content. In the case above, the output should be:

this is a first sentence
hello my name is Chris 
what's up man
today is tuesday

as you can see, the 3rd String has been modified and now contains only one statement what's up man instead of two of them. In my list there is a situation that sometimes the String is correct, and sometimes it is doubled as shown above.

I want to get rid of it, so I thought about iterating through this list:

for (String s: myList) {

but I cannot find a way of eliminating duplicates, especially since the length of each string is not determined, and by that I mean there might be record:

this is a very long sentence this is a very long sentence

or sometimes short ones:

single word singe word

is there some native java function for that maybe?

Answer 1

Assuming the String is repeated just twice, and with an space in between as in your examples, the following code would remove repetitions:

for (int i=0; i<myList.size(); i++) {
    String s = myList.get(i);
    String fs = s.substring(0, s.length()/2);
    String ls = s.substring(s.length()/2+1, s.length());
    if (fs.equals(ls)) {
        myList.set(i, fs);
    }
}

The code just split each entry of the list into two substrings (dividing by the half point). If both are equal, substitute the original element with only one half, thus removing the repetition.

I was testing the code and did not see @Brendan Robert answer. This code follows the same logic as his answer.