src/org/nutz/lang/Strings.java
public static boolean isUrl(String s) {
        try {
            new java.net.URL(s);
        }
        catch (MalformedURLException e) {
            return false;
        }
        return true;
    }
public static boolean isUrl(String s) {
        try {
            new java.net.URL(s);
        }
        catch (MalformedURLException e) {
            return false;
        }
        return true;
    }
判断字符串是否为URL

@param s
字符串内容
@return 判断结果