Boyer–Moore string search algorithm.

BoyerMooreSearch.java

/**
* Search if a string (pattern) is contained in another string (text)
* according to the Boyer–Moore string search algorithm.
* 
* @param pattern string to search for
* @param text string to search in
* @return true if text contains pattern, otherwise false
*/
public static Boolean search(String pattern, String text) {

	if (null == pattern || pattern.isEmpty()) return false;
	if (null == text || text.isEmpty()) return false;
	if (pattern.length() > text.length()) return false;

	int textLength = text.length();
	int patternLength = pattern.length();

	int textIndex = patternLength - 1;
	int patternIndex = patternLength - 1;

	while (textIndex < textLength) {

		if (pattern.charAt(patternIndex) == text.charAt(textIndex)) {
			if (patternIndex == 0) return true;
			textIndex--;
			patternIndex--;
		} else {
  			textIndex += patternLength - Math.min(patternIndex, textLength + 1);
			patternIndex = patternLength - 1;
		}
	}

	return false;
}