ShortestWordDistance.java

public int shortestDistance(String[] words, String word1, String word2) {
    if (words == null || words.length == 0 || word1 == null || word2 == null || word1.equals(word2)) {
        return -1;
    }
    int minDistance = words.length;

    int wordIndex1 = -1;
    int wordIndex2 = -1;

    for (int i = 0; i < words.length; i++) {
        if (words[i].equals(word1)) {
            wordIndex1 = i;
            if (wordIndex2 != -1) {
                minDistance = Math.min(minDistance, Math.abs(wordIndex1 - wordIndex2));
            }
        }
        if (words[i].equals(word2)) {
            wordIndex2 = i;
            if (wordIndex1 != -1) {
                minDistance = Math.min(minDistance, Math.abs(wordIndex1 - wordIndex2));
            }
        }
    }

    return minDistance;
}