Simple Framework中的自定义匹配器用于反序列化但不能序列化

Question

I'm trying to get Simple to play nice with XMLGregorianCalendar. In so doing I've created a Matcher and Transform:

public class MyMatcher implements Matcher {

    @Override
    public Transform<?> match(@SuppressWarnings("rawtypes") final Class type) throws Exception {
        if (type.equals(XMLGregorianCalendar.class)) {
            return new XMLGregorianCalendarTransform();
        }

        return null;
    }

}

and

public class XMLGregorianCalendarTransform implements Transform<XMLGregorianCalendar> {

    @Override
    public XMLGregorianCalendar read(final String value) throws Exception {
        return DatatypeFactory.newInstance().newXMLGregorianCalendar(value);
    }

    @Override
    public String write(final XMLGregorianCalendar value) throws Exception {
        return value.toXMLFormat();
    }

}

When this code is used to deserialize, it works great:

        final Serializer serializer = new Persister(new MyMatcher());
        obj = serializer.read(type, new ByteArrayInputStream(xml.getBytes(Charset.forName(UTF8_ENCODING))));

Unfortunately when I try to use it to serialize, it doesn't work, it throws the Failed to create xml string for the object. org.simpleframework.xml.transform.TransformException: Transform of class com.sun.org.apache.xerces.internal.jaxp.datatyp e.XMLGregorianCalendarImpl not supported Failed to create xml string for the object. org.simpleframework.xml.transform.TransformException: Transform of class com.sun.org.apache.xerces.internal.jaxp.datatyp e.XMLGregorianCalendarImpl not supported error, my Transform's write method is never called (check by break point).

Here's the code I use to serialize:

        final ByteArrayOutputStream baos = new ByteArrayOutputStream();
        os = new DataOutputStream(baos);
        final Serializer serializer = new Persister(new MyMatcher());
        serializer.write(this, os);
        os.flush();
        xmlString = new String(baos.toByteArray(), Charset.forName(UTF8_ENCODING));

The write method throws the exception. I've used Serialization third-party classes with Simple XML (org.simpleframework.xml) as a reference, and it's what got me to the deserialization working, but now I'm stuck. I'm not sure how to proceed.

Any help is appreciated.

Answer 1

It turns out the answer was in the question. The error stated XMLGregorianCalendarImpl not supported. This is not what my Matcher checked for. I just had to change:

    if (type.equals(XMLGregorianCalendar.class)) {

to

    if (XMLGregorianCalendar.class.isAssignableFrom(type)) {

I hope this helps someone.