Java constructor with method that creates instance of that object

Question

I want to create constructor which takes xml as string and all variables would be fill from that. That xml is created by XStream so I think that something like this would work but don´t know what to add to left side:

    public xmlpacket(String xml)
    {
        XStream xstream = new XStream(new DomDriver());
       .... =  (xmlpacket)xstream.fromXML(xml);
    }

Thank you

http://xstream.codehaus.org/tutorial.html – pap May 03 '12 at 10:57 — pap, May 03 '12 at 10:57

score 1 · Accepted Answer · answered May 03 '12 at 10:59

You can make use of a static method.

public static XMLPacket unmarshall(String xml) {
    XStream xstream = new XStream(new DomDriver());

    return (XMLPacket)xstream.fromXML(xml);

}

Notice how I renamed your class. Now it adheres to Java Naming Conventions.

score 1 · Answer 2 · answered May 03 '12 at 11:04

1

If you've created the classes you need and the xstream aliases for the classes then

XMLPacket packet = (XMLPacket)xstream.fromXML(xml);

But you should probably create a method for this and not do it in the constructor.

answered May 03 '12 at 11:04

ChadNC

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score 0 · Answer 3 · answered May 03 '12 at 11:04

XStream will create the instance of the object for you. So unless you want to copy all the attributes of the XStream-created packet to the packet you're constructing, it makes no sense to do that in a constructor. Create a factory method instead:

public static XmlPacket fromXml(String xml) {
    XStream xstream = new XStream(new DomDriver());
    return (XmlPacket) xstream.fromXML(xml);
}

Java constructor with method that creates instance of that object

3 Answers3