markwon-html/src/main/java/ru/noties/markwon/html/jsoup/helper/Validate.java
public static void notEmpty(String string, String msg) {
        if (string == null || string.length() == 0)
            throw new IllegalArgumentException(msg);
    }
public static void notEmpty(String string, String msg) {
        if (string == null || string.length() == 0)
            throw new IllegalArgumentException(msg);
    }
Validates that the string is not empty
@param string the string to test
@param msg message to output if validation fails