StringUtils empty check

We often would check if a String object is null or empty, so here is the code snippet

public static boolean isEmpty(String s) {
    return s==null||s.trim().length()==0;
}
public static boolean isNotEmpty(String s) {
    return !isEmpty(s);
}
/**
 * check if all params is empty
 */
public static boolean isNotEmpty(String ... params) {
    boolean foundEmpty = false;
    for(String param:params) {
        if(isEmpty(param)) {
            foundEmpty = true;
            break;
        }
    }
    if(!foundEmpty) {
        return true;
    }
    return false;
}