PatternMatchUtils.java

package org.googlecode.perftrace.aopmatcher.support;

/**
 * Utility methods for simple pattern matching, in particular for
 * Spring's typical "xxx*", "*xxx" and "*xxx*" pattern styles.
 * 
 */
public abstract class PatternMatchUtils {

	/**
	 * Match a String against the given pattern, supporting the following simple
	 * pattern styles: "xxx*", "*xxx", "*xxx*" and "xxx*yyy" matches (with an
	 * arbitrary number of pattern parts), as well as direct equality.
	 * @param pattern the pattern to match against
	 * @param str the String to match
	 * @return whether the String matches the given pattern
	 */
	public static boolean simpleMatch(String pattern, String str) {
		if (pattern == null || str == null) {
			return false;
		}
		int firstIndex = pattern.indexOf('*');
		if (firstIndex == -1) {
			return pattern.equals(str);
		}
		if (firstIndex == 0) {
			if (pattern.length() == 1) {
				return true;
			}
			int nextIndex = pattern.indexOf('*', firstIndex + 1);
			if (nextIndex == -1) {
				return str.endsWith(pattern.substring(1));
			}
			String part = pattern.substring(1, nextIndex);
			int partIndex = str.indexOf(part);
			while (partIndex != -1) {
				if (simpleMatch(pattern.substring(nextIndex), str.substring(partIndex + part.length()))) {
					return true;
				}
				partIndex = str.indexOf(part, partIndex + 1);
			}
			return false;
		}
		return (str.length() >= firstIndex &&
				pattern.substring(0, firstIndex).equals(str.substring(0, firstIndex)) &&
				simpleMatch(pattern.substring(firstIndex), str.substring(firstIndex)));
	}

	/**
	 * Match a String against the given patterns, supporting the following simple
	 * pattern styles: "xxx*", "*xxx", "*xxx*" and "xxx*yyy" matches (with an
	 * arbitrary number of pattern parts), as well as direct equality.
	 * @param patterns the patterns to match against
	 * @param str the String to match
	 * @return whether the String matches any of the given patterns
	 */
	public static boolean simpleMatch(String[] patterns, String str) {
		if (patterns != null) {
			for (int i = 0; i < patterns.length; i++) {
				if (simpleMatch(patterns[i], str)) {
					return true;
				}
			}
		}
		return false;
	}

}