package caseStudy;

public abstract class SaveAsXML {
    public static String findInXML(String xml, String startTag, String endTag) {
        if (xml.isEmpty() || xml.indexOf(startTag) < 0) {
            return null;
        }
        return xml.substring(xml.indexOf(startTag) + startTag.length(), xml.indexOf(endTag));
    }
    public static String removeFirst(String xml, String startTag, String endTag) {
        if(xml.isEmpty()) {
            return null;
        }
        String beforeTag = xml.substring(0, xml.indexOf(startTag));
        String afterTag = xml.substring(xml.indexOf(endTag) + endTag.length());
        return beforeTag + afterTag;
    }
    abstract public String save();
    abstract public void load(String xml);
}