JAXB 或 JAX-RS 在我的 JSON 响应中用引号包裹数字，将它们变成字符串.为什么这是默认行为，以及如何解决?

To configure MOXy as your JSON-binding provider in a JAX-RS environment, you could create a MessageBodyReader/MessageBodyWriter that looks like:

import java.io.*;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;
import java.util.Collection;
import javax.xml.transform.stream.StreamSource;

import javax.ws.rs.*;
import javax.ws.rs.core.*;
import javax.ws.rs.ext.*;
import javax.xml.bind.*;

@Provider
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public class MOXyJSONProvider implements 
    MessageBodyReader<Object>, MessageBodyWriter<Object>{

    @Context
    protected Providers providers;

    public boolean isReadable(Class<?> type, Type genericType,
        Annotation[] annotations, MediaType mediaType) {
        return true;
    }

    public Object readFrom(Class<Object> type, Type genericType,
        Annotation[] annotations, MediaType mediaType,
        MultivaluedMap<String, String> httpHeaders, InputStream entityStream)
        throws IOException, WebApplicationException {
        try {
            Unmarshaller u = getJAXBContext(type, mediaType).createUnmarshaller();
            u.setProperty("eclipselink.media-type", mediaType.toString());
            u.setProperty("eclipselink.json.include-root", false);//tiny fix
            return u.unmarshal(new StreamSource(entityStream), (Class) genericType);
        } catch(JAXBException jaxbException) {
            throw new WebApplicationException(jaxbException);
        }
    }

    public boolean isWriteable(Class<?> type, Type genericType,
        Annotation[] annotations, MediaType mediaType) {
        return true;
    }

    public void writeTo(Object object, Class<?> type, Type genericType,
        Annotation[] annotations, MediaType mediaType,
        MultivaluedMap<String, Object> httpHeaders,
        OutputStream entityStream) throws IOException,
        WebApplicationException {
        try {
            Marshaller m = getJAXBContext(Customer.class, mediaType).createMarshaller();
            m.setProperty("eclipselink.media-type", mediaType.toString());
            m.setProperty("eclipselink.json.include-root", false);
            m.marshal(object, entityStream);
        } catch(JAXBException jaxbException) {
            throw new WebApplicationException(jaxbException);
        }
    }

    public long getSize(Object t, Class<?> type, Type genericType,
        Annotation[] annotations, MediaType mediaType) {
        return -1;
    }

    private JAXBContext getJAXBContext(Class<?> type, MediaType mediaType) 
        throws JAXBException {
        ContextResolver<JAXBContext> resolver 
            = providers.getContextResolver(JAXBContext.class, mediaType);
        JAXBContext jaxbContext;
        if(null == resolver || null == (jaxbContext = resolver.getContext(type))) {
            return JAXBContext.newInstance(type);
        } else {
            return jaxbContext;
        }
    }

}

更多信息

• https://stackoverflow.com/a/8989659/383861
• http://blog.bdoughan.com/2010/08/creating-restful-web-service-part-15.html
• http://blog.bdoughan.com/2011/04/moxys-xml-metadata-in-jax-rs-service.html