AtomFeedSyndFeedProvider.java

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 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
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package org.apache.wink.common.internal.providers.entity.atom;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;

import javax.ws.rs.Consumes;
import javax.ws.rs.Produces;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.ext.MessageBodyReader;
import javax.ws.rs.ext.MessageBodyWriter;
import javax.ws.rs.ext.Provider;
import javax.ws.rs.ext.Providers;

import org.apache.wink.common.internal.utils.MediaTypeUtils;
import org.apache.wink.common.model.atom.AtomFeed;
import org.apache.wink.common.model.synd.SyndFeed;

@Provider
@Consumes( {MediaType.APPLICATION_ATOM_XML, MediaType.APPLICATION_JSON, MediaTypeUtils.JAVASCRIPT})
@Produces( {MediaType.APPLICATION_ATOM_XML, MediaType.APPLICATION_JSON, MediaTypeUtils.JAVASCRIPT})
public class AtomFeedSyndFeedProvider implements MessageBodyReader<SyndFeed>,
    MessageBodyWriter<SyndFeed> {
    
    @Context
    private Providers providers;

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

    public SyndFeed readFrom(Class<SyndFeed> type,
                             Type genericType,
                             Annotation[] annotations,
                             MediaType mediaType,
                             MultivaluedMap<String, String> httpHeaders,
                             InputStream entityStream) throws IOException, WebApplicationException {

        MessageBodyReader<AtomFeed> reader =
            providers.getMessageBodyReader(AtomFeed.class, genericType, annotations, mediaType);
        AtomFeed feed =
            reader.readFrom(AtomFeed.class,
                            genericType,
                            annotations,
                            mediaType,
                            httpHeaders,
                            entityStream);
        return feed.toSynd(new SyndFeed());
    }

    public boolean isWriteable(Class<?> type,
                               Type genericType,
                               Annotation[] annotations,
                               MediaType mediaType) {
        MessageBodyWriter<AtomFeed> writer =
            providers.getMessageBodyWriter(AtomFeed.class, genericType, annotations, mediaType);
        return ((type.isAssignableFrom(SyndFeed.class)) && (writer != null));
    }

    public void writeTo(SyndFeed t,
                        Class<?> type,
                        Type genericType,
                        Annotation[] annotations,
                        MediaType mediaType,
                        MultivaluedMap<String, Object> httpHeaders,
                        OutputStream entityStream) throws IOException, WebApplicationException {
        AtomFeed feed = new AtomFeed(t);
        MessageBodyWriter<AtomFeed> writer =
            providers.getMessageBodyWriter(AtomFeed.class, genericType, annotations, mediaType);

        // already checked for non-null writer in isWriteable
        
        writer.writeTo(feed,
                       AtomFeed.class,
                       genericType,
                       annotations,
                       mediaType,
                       httpHeaders,
                       entityStream);
    }

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