MessageBodyWorkers.java

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package com.sun.jersey.spi;

import java.lang.annotation.Annotation;
import java.lang.reflect.Type;
import java.util.List;
import java.util.Map;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.ext.MessageBodyReader;
import javax.ws.rs.ext.MessageBodyWriter;
        
/**
 * An injectable interface providing lookup of {@link MessageBodyReader} and
 * {@link MessageBodyWriter} instances. 
 * 
 * @see javax.ws.rs.core.Context
 * @see MessageBodyReader
 * @see MessageBodyWriter
 * @author Paul.Sandoz@Sun.Com
 */
public interface MessageBodyWorkers {
    /**
     * Get the map of media type to list of message body writers that are
     * compatible with a media type.
     * 
     * @param mediaType the compatible media type.
     * @return the map of media type to list of message body writers.
     */
    public Map<MediaType, List<MessageBodyReader>> getReaders(MediaType mediaType);

    /**
     * Get the map of media type to list of message body writers that are
     * compatible with a media type.
     *
     * @param mediaType the compatible media type.
     * @return the map of media type to list of message body writers.
     */
    public Map<MediaType, List<MessageBodyWriter>> getWriters(MediaType mediaType);

    /**
     * Convert a map media type to list of message body readers to a string.
     * 
     * @param readers the map media type to list of message body readers
     * @return the string representation.
     */
    public String readersToString(Map<MediaType, List<MessageBodyReader>> readers);

    /**
     * Convert a map media type to list of message body writers to a string.
     *
     * @param writers the map media type to list of message body readers
     * @return the string representation.
     */
    public String writersToString(Map<MediaType, List<MessageBodyWriter>> writers);

    /**
     * Get a message body reader that matches a set of criteria.
     * 
     * @param <T> the type of object to be read.
     *
     * @param mediaType the media type of the data that will be read, this will
     * be compared to the values of {@link javax.ws.rs.Consumes} for
     * each candidate reader and only matching readers will be queried.
     * 
     * @param type the class of object to be read.
     * 
     * @param genericType the type of object to be produced. E.g. if the 
     * message body is to be converted into a method parameter, this will be
     * the formal type of the method parameter as returned by 
     * <code>Class.getGenericParameterTypes</code>.
     * 
     * @param annotations an array of the annotations on the declaration of the
     * artifact that will be initialized with the produced instance. E.g. if the 
     * message body is to be converted into a method parameter, this will be
     * the annotations on that parameter returned by 
     * <code>Class.getParameterAnnotations</code>.
     * 
     * @return a MessageBodyReader that matches the supplied criteria or null
     * if none is found.
     */
    <T> MessageBodyReader<T> getMessageBodyReader(Class<T> type, Type genericType, 
            Annotation annotations[], MediaType mediaType);
    
    /**
     * Get a message body writer that matches a set of criteria.
     * 
     * @param <T> the type of the object that is to be written.
     * 
     * @param mediaType the media type of the data that will be written, this will
     * be compared to the values of {@link javax.ws.rs.Produces} for
     * each candidate writer and only matching writers will be queried.
     * 
     * @param type the class of object that is to be written.
     * 
     * @param genericType the type of object to be written. E.g. if the 
     * message body is to be produced from a field, this will be
     * the declared type of the field as returned by 
     * <code>Field.getGenericType</code>.
     * 
     * @param annotations an array of the annotations on the declaration of the
     * artifact that will be written. E.g. if the 
     * message body is to be produced from a field, this will be
     * the annotations on that field returned by 
     * <code>Field.getDeclaredAnnotations</code>.
     * 
     * @return a MessageBodyReader that matches the supplied criteria or null
     * if none is found.
     */
    <T> MessageBodyWriter<T> getMessageBodyWriter(Class<T> type, Type genericType, 
            Annotation annotations[], MediaType mediaType);
    
    /**
     * Get the list of media types supported for a Java type.
     * 
     * @param <T> the type of object that is to be written.
     * 
     * @param type the class of object that is to be written.
     * 
     * @param genericType the type of object to be written. E.g. if the 
     * message body is to be produced from a field, this will be
     * the declared type of the field as returned by 
     * <code>Field.getGenericType</code>.
     * 
     * @param annotations an array of the annotations on the declaration of the
     * artifact that will be written. E.g. if the 
     * message body is to be produced from a field, this will be
     * the annotations on that field returned by 
     * <code>Field.getDeclaredAnnotations</code>.
     * 
     * @return the list of supported media types, the list is ordered as
     * follows: a/b < a/* < *\\/*
     */
    <T> List<MediaType> getMessageBodyWriterMediaTypes(
            Class<T> type, 
            Type genericType,
            Annotation[] annotations);

    /**
     * Get the most acceptable media type supported for a Java type given a set
     * of acceptable media types.
     *
     * @param <T> the type of object that is to be written.
     *
     * @param type the class of object that is to be written.
     *
     * @param genericType the type of object to be written. E.g. if the
     * message body is to be produced from a field, this will be
     * the declared type of the field as returned by
     * <code>Field.getGenericType</code>.
     *
     * @param annotations an array of the annotations on the declaration of the
     * artifact that will be written. E.g. if the
     * message body is to be produced from a field, this will be
     * the annotations on that field returned by
     * <code>Field.getDeclaredAnnotations</code>.
     *
     * @param acceptableMediaTypes the list of acceptable media types, sorted
     *        according to the quality with the media type of highest quality
     *        occurring first first.
     * @return the best media types
     */
    <T> MediaType getMessageBodyWriterMediaType(
            Class<T> type,
            Type genericType,
			Annotation[] annotations,
            List<MediaType> acceptableMediaTypes);
}