Re: [Simple-support] Transitioning from ElementList to ElementMap

[Niall G. - Y. <Nia...@yi...>]

On the @Element use required=false

From: Kiran Rao [mailto:tec...@gm...]
Sent: Thursday, 17 January 2013 1:53 AM
To: simple-support
Subject: [Simple-support] Transitioning from ElementList to ElementMap

I have an XML format that looks like this:
<devices>
    <device id="10">
        <name>Nexus 7</name>
        <os>Android</os>
    </device>
    <device id="20">
        <name>Samsung Galaxy S3</name>
        <os>Android</os>
    </device>
    <device id="30">
        <name>Apple iPad3</name>
        <os>iOS</os>
    </device>
</devices>

Currently, I am treating this as an ElementList as follows:
@Root(name="devices")
class Devices{
    @ElementList(inline="true")
    List<Device> devices;
    // ... Constructors, getters, setters
}
@Root(name="device")
class Device{
    @Attribute(name="id")
    long id;
    @Element(name="name")
    String name;
    @Element(name="os")
    String os;

    //... Constructors, getters, setters
}

So far, so good. I have been parsing this as an ArrayList. However, I almost always want to access a device by ID, not by its position. So, I thought, I'd instead parse this as a Map, not a List. I can map a device ID to the device object itself.
I tried to use ElementMap annotation, but I can't seem to get it right. Here's what I've tried:

@Root(name="devices")
public class DeviceMap {

    @ElementMap(entry="device", key="id",  attribute = true, inline = true)
    private Map<Long, Device> map;

    public Map<Long, Device> getMap(){
        return this.map;
    }
}

@Root(name = "device")
public class Device {
    @Element(name="os")
    String os;

    @Element(name="name")
    String name;

    //... Constructors, getters, setters}
}
However, this fails with a ValueRequiredException:

org.simpleframework.xml.core.ValueRequiredException: Unable to satisfy @org.simpleframework.xml.Element(name=OS, data=false, required=true, type=void) on field 'os' java.lang.String


Note that the value of the Map in my case turns out to be neither a primitive, nor an object - it is a bunch of what would have been inline elements.

Any pointers on how to proceed with this?

--
Regards,
=======
Kiran Rao
http://curioustechizen.blogspot.com/
http://stackoverflow.com/users/570930/curioustechizen