/**

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

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 * The Original Software is NetBeans. The Initial Developer of the Original

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package org.netbeans.html.json.spi;

import java.io.IOException;

import java.io.InputStream;

import org.netbeans.html.context.spi.Contexts.Builder;

import org.netbeans.html.context.spi.Contexts.Id;

/** A {@link Builder service provider interface} responsible for 

 * conversion of JSON objects to Java ones and vice-versa.

 * Since introduction of {@link Id technology identifiers} one can choose between

 * different background implementations to handle the conversion and

 * communication requests. The known providers include

 * <code>org.netbeans.html:ko4j</code> module which registers 

 * a native browser implementation called <b>xhr</b>, and a

 * <code>org.netbeans.html:ko-ws-tyrus</code> module which registers 

 * Java based implementation named <b>tyrus</b>.

 *

 * @author Jaroslav Tulach

 */

public interface Transfer {

    /**

     * Called to inspect properties of an object (usually a JSON or JavaScript

     * wrapper).

     *

     * @param obj the object to inspect

     * @param props the names of properties to check on the object

     * <code>obj</code>

     * @param values array of the same length as <code>props</code> should be

     * filled by values of properties on the <code>obj</code>. If a property is

     * not defined, a <code>null</code> value should be stored in the array

     */

    public void extract(Object obj, String[] props, Object[] values);

    /** Reads content of a stream and creates its JSON representation.

     * The returned object is implementation dependant. It however needs

     * to be acceptable as first argument of {@link #extract(java.lang.Object, java.lang.String[], java.lang.Object[]) extract}

     * method. If the stream contains representation or a JSON array,

     * an Object[] should be returned - each of its members should, by itself

     * be acceptable argument to 

     * the {@link #extract(java.lang.Object, java.lang.String[], java.lang.Object[]) extract} method.

     * 

     * @param is input stream to read data from

     * @return an object representing the JSON data

     * @throws IOException if something goes wrong

     */

    public Object toJSON(InputStream is) throws IOException;

    /** Starts the JSON or JSONP query. 

     * 

     * @param call description of the call to make

     */

    public void loadJSON(JSONCall call);

}