Question

How can I serialize java.util.concurrent.TimeUnit with the Simple XML lib (version 2.6.5 / 2.6.6)?

Here’s my class I want to serialize:

@Root(name="settings")
public class Config
{
    // some more code

    @Element(name="timeunit", required=true)
    private static final TimeUnit timeunit = TimeUnit.SECONDS;


    // some more code
}

Using Simple:

File f = // ...
Config cfg = new Config();
Serializer ser = new Persister();

ser.write(cfg, f);

And I’m getting this Exception:

org.simpleframework.xml.transform.TransformException: Transform of class java.util.concurrent.TimeUnit$4 not supported

I tested other Annotations like @Default so far, but same problem. Wondering why Simple has a problem with TimeUnits – all other Types (Classes / primitive Types) work without any problem.

Answer 1

Here’s a possible solution:

Annotation:

@Element(name="timeunit", required=true)
@Convert(TimeUnitConverter.class)
private static final TimeUnit timeunit = TimeUnit.SECONDS;

Converter:

public class TimeUnitConverter implements Converter<TimeUnit>
{
    @Override
    public TimeUnit read(InputNode node) throws Exception
    {
        return TimeUnit.valueOf(node.getValue().toUpperCase());
    }


    @Override
    public void write(OutputNode node, TimeUnit value) throws Exception
    {
        node.getAttributes().remove("class"); /* Not required */
        node.setValue(value.toString().toLowerCase());
    }

}