How do you match the individual words as separate words in the input sentence in a string that has just one word

Question

I want to see if multiple words found inside the string. With O(n^2) complexity. For example: sunshine - sun, shine, hine. And will print collection of strings: sun shine and hine if it matches. How do I check if a string contains a matching words?

//String search = sunshine 
public static boolean wordsInsideTheString(String search) { 
    String[] word = {"sun", "shine", "hine"};
    int counter = 0;    
    for(int i = 0; i < word.length; i++) {      
       String[] words = word[i].split("\\s+");
       for (String check : words) 
           if(check.equalsIgnoreCase(search)) {
               counter++;
               break;
           } 
       }    
    return false;
}

Calling the method with:

assert.True(wordsInsideTheString("sunshine");

Answer 1

If you just want to assert whether or not an input string matches a collection of words, then use String#matches :

public static boolean wordsInsideTheString(String search) { 
    String[] word = {"sun", "shine", "hine"};
    List<String> wordList = Arrays.asList(word);
    String regex = ".*(?:" + String.join("|", wordList) + ").*";

    return search.matches(regex);
}

If instead you also want to print which of the terms did match, then we need to do a bit more work. I suggest just iterating the array of word terms and again using String#matches :

public static boolean wordsInsideTheString(String search) { 
    String[] words = {"sun", "shine", "hine"};
    List<String> matches = new ArrayList<>();
    boolean match = false;
    for (String word : words) {
        if (search.contains(word)) {
            match = true;
            matches.add(word);
        }
    }
    System.out.println("Matching words: " + String.join(",", matches));

    return match;
}