void init() {
        for (MimeType type : types.values()) {
            magics.addAll(type.getMagics());
            if (type.hasRootXML()) {
                xmls.add(type);
            }
        }
        Collections.sort(magics);
        Collections.sort(xmls);
    }
Called after all configured types have been loaded.
Initializes the magics and xmls sets.
tika-core/src/main/java/org/apache/tika/mime/MimeTypes.java