/**

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

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  * Copyright 2013-2014 Oracle and/or its affiliates. All rights reserved.

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  * Development and Distribution License("CDDL") (collectively, the

  * "License"). You may not use this file except in compliance with the

  * License. You can obtain a copy of the License at

  * http://www.netbeans.org/cddl-gplv2.html

  * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the

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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);

 }