String insertData (String template){

    template=template.replace("###menu1Link###",tbMenu1Link.getText());
    template=template.replace("###menu1Title###",tbMenu1Title.getText());
    template=template.replace("###content###",epContent.getText());
    template=template.replace("###footer###",epFooter.getText());
    template=template.replace("###image1###",jfc2.getSelectedFile().getPath());
    template=template.replace("###image2###",jfc2.getSelectedFile().getPath());

    return template ;
}

void doStuff(String template) {

        Map<String,String> vars = new HashMap<String, String>();
        vars.put("###menu1Link###",tbMenu1Link.getText());
        vars.put("###menu1Title###",tbMenu1Title.getText());
        vars.put("###content###",epContent.getText());
        //...
        String templateWithData = insertData(template, vars);
    }

    String insertData (String template, Map<String, String> vars){
        for (String key : vars.keySet()) {
            template = template.replace(key, vars.get(key));
        }
        return template ;
    }

... <a href="###menu1Link###">###menu1Title###</a> ...

... <a href="%s">%s</a> ...

String insertData(String template) {
    return String.format(template,
        tbMenu1Link.getText(),
        tbMenu1Title.getText()
    );
}