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/*
 * oauth2-oidc-sdk
 *
 * Copyright 2012-2016, Connect2id Ltd and contributors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
 * this file except in compliance with the License. You may obtain a copy of the
 * License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed
 * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
 * CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 */

package com.nimbusds.oauth2.sdk.util;


import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.*;

import net.minidev.json.JSONArray;
import net.minidev.json.JSONObject;

import com.nimbusds.jose.jwk.JWKSet;
import com.nimbusds.jwt.JWTClaimsSet;
import com.nimbusds.oauth2.sdk.ParseException;


/**
 * JSON object helper methods for parsing and typed retrieval of member values.
 */
public final class JSONObjectUtils {
	
	
	/**
	 * Returns {@code true} if the JSON object is defined and contains the 
	 * specified key.
	 *
	 * @param jsonObject The JSON object to check. May be {@code null}.
	 * @param key        The key to check. Must not be {@code null}.
	 *
	 * @return {@code true} if the JSON object is defined and contains the
	 *         specified key, else {@code false}.
	 */
	public static boolean containsKey(final JSONObject jsonObject, final String key) {

		return jsonObject != null && jsonObject.containsKey(key);
	}
	
	
	/**
	 * Parses a JSON object.
	 *
	 * 
Specific JSON to Java entity mapping (as per JSON Simple):
	 *
	 * 
    
	 *     
  • JSON numbers mapped to {@code java.lang.Number}.
	 *     
  • JSON integer numbers mapped to {@code long}.
	 *     
  • JSON fraction numbers mapped to {@code double}.
	 * 

	 *
	 * @param s The JSON object string to parse. Must not be {@code null}.
	 *
	 * @return The JSON object.
	 *
	 * @throws ParseException If the string cannot be parsed to a JSON 
	 *                        object.
	 */
	public static JSONObject parse(final String s)
		throws ParseException {
		
		Object o = JSONUtils.parseJSON(s);
		
		if (o instanceof JSONObject)
			return (JSONObject)o;
		else
			throw new ParseException("The JSON entity is not an object");
	}
	
	
	/**
	 * Parses a JSON object while keeping the order of JSON object members.
	 *
	 * 
Specific JSON to Java entity mapping (as per JSON Simple):
	 *
	 * 
    
	 *     
  • JSON numbers mapped to {@code java.lang.Number}.
	 *     
  • JSON integer numbers mapped to {@code long}.
	 *     
  • JSON fraction numbers mapped to {@code double}.
	 * 

	 *
	 * @param s The JSON object string to parse. Must not be {@code null}.
	 *
	 * @return The JSON object as linked hash map.
	 *
	 * @throws ParseException If the string cannot be parsed to a JSON
	 *                        object.
	 */
	public static LinkedHashMap parseKeepingOrder(final String s)
		throws ParseException {
		
		Object o = JSONUtils.parseJSONKeepingOrder(s);
		
		if (o instanceof LinkedHashMap)
			return (LinkedHashMap)o;
		else
			throw new ParseException("The JSON entity is not an object");
	}


	/**
	 * Use {@link #parse(String)} instead.
	 *
	 * @param s The JSON object string to parse. Must not be {@code null}.
	 *
	 * @return The JSON object.
	 *
	 * @throws ParseException If the string cannot be parsed to a JSON
	 *                        object.
	 */
	@Deprecated
	public static JSONObject parseJSONObject(final String s)
		throws ParseException {

		return parse(s);
	}
	
	
	/**
	 * Gets a generic member of a JSON object.
	 *
	 * @param o     The JSON object. Must not be {@code null}.
	 * @param key   The JSON object member key. Must not be {@code null}.
	 * @param clazz The expected class of the JSON object member value. Must
	 *              not be {@code null}.
	 *
	 * @return The JSON object member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static  T getGeneric(final JSONObject o, final String key, final Class clazz)
		throws ParseException {
	
		if (! o.containsKey(key))
			throw new ParseException("Missing JSON object member with key " + key + "");
		
		Object value = o.get(key);
		
		if (value == null) {
			throw new ParseException("JSON object member with key " + key + " has null value");
		}
		
		try {
			return JSONUtils.to(value, clazz);
		} catch (ParseException e) {
			throw new ParseException("Unexpected type of JSON object member with key " + key + "", e);
		}
	}


	/**
	 * Gets a boolean member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static boolean getBoolean(final JSONObject o, final String key)
		throws ParseException {
		
		return getGeneric(o, key, Boolean.class);
	}


	/**
	 * Gets a boolean member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or.
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static boolean getBoolean(final JSONObject o, final String key, final boolean def)
		throws ParseException {
		
		if (o.get(key) != null) {
			return getBoolean(o, key);
		}
		
		return def;
	}
	
	
	/**
	 * Gets an number member of a JSON object as {@code int}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static int getInt(final JSONObject o, final String key)
		throws ParseException {
		
		return getGeneric(o, key, Number.class).intValue();	
	}
	
	
	/**
	 * Gets an number member of a JSON object as {@code int}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static int getInt(final JSONObject o, final String key, final int def)
		throws ParseException {
		
		if (o.get(key) != null) {
			return getInt(o, key);
		}
		
		return def;
	}
	
	
	/**
	 * Gets a number member of a JSON object as {@code long}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static long getLong(final JSONObject o, final String key)
		throws ParseException {
		
		return getGeneric(o, key, Number.class).longValue();
	}
	
	
	/**
	 * Gets a number member of a JSON object as {@code long}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static long getLong(final JSONObject o, final String key, final long def)
		throws ParseException {
		
		if (o.get(key) != null) {
			return getLong(o, key);
		}
		
		return def;
	}
	
	
	/**
	 * Gets a number member of a JSON object {@code float}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static float getFloat(final JSONObject o, final String key)
		throws ParseException {
		
		return getGeneric(o, key, Number.class).floatValue();
	}
	
	
	/**
	 * Gets a number member of a JSON object {@code float}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static float getFloat(final JSONObject o, final String key, final float def)
		throws ParseException {
		
		if (o.get(key) != null) {
			return getFloat(o, key);
		}
		
		return def;
	}
	
	
	/**
	 * Gets a number member of a JSON object as {@code double}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static double getDouble(final JSONObject o, final String key)
		throws ParseException {
		
		return getGeneric(o, key, Number.class).doubleValue();
	}
	
	
	/**
	 * Gets a number member of a JSON object as {@code double}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static double getDouble(final JSONObject o, final String key, final double def)
		throws ParseException {
		
		if (o.get(key) != null) {
			return getDouble(o, key);
		}
		
		return def;
	}


	/**
	 * Gets a number member of a JSON object as {@code java.lang.Number}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static Number getNumber(final JSONObject o, final String key)
		throws ParseException {

		return getGeneric(o, key, Number.class);
	}


	/**
	 * Gets a number member of a JSON object as {@code java.lang.Number}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static Number getNumber(final JSONObject o, final String key, final Number def)
		throws ParseException {

		if (o.get(key) != null) {
			return getNumber(o, key);
		}
		
		return def;
	}
	
	
	/**
	 * Gets a string member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static String getString(final JSONObject o, final String key)
		throws ParseException {
		
		return getGeneric(o, key, String.class);
	}
	
	
	/**
	 * Gets a string member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static String getString(final JSONObject o, final String key, final String def)
		throws ParseException {
		
		if (o.get(key) != null) {
			return getString(o, key);
		}
		
		return def;
	}


	/**
	 * Gets a string member of a JSON object as an enumerated object.
	 *
	 * @param o         The JSON object. Must not be {@code null}.
	 * @param key       The JSON object member key. Must not be
	 *                  {@code null}.
	 * @param enumClass The enumeration class. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static > T getEnum(final JSONObject o, 
		                                    final String key,
		                                    final Class enumClass)
		throws ParseException {

		String value = getString(o, key);

		for (T en: enumClass.getEnumConstants()) {
			       
			if (en.toString().equalsIgnoreCase(value))
				return en;
		}

		throw new ParseException("Unexpected value of JSON object member with key " + key + "");
	}


	/**
	 * Gets a string member of a JSON object as an enumerated object.
	 *
	 * @param o         The JSON object. Must not be {@code null}.
	 * @param key       The JSON object member key. Must not be
	 *                  {@code null}.
	 * @param enumClass The enumeration class. Must not be {@code null}.
	 * @param def       The default value to return if the key is not
	 *                  present or the value is {@code null}. May be
	 *                  {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static > T getEnum(final JSONObject o,
		                                    final String key,
		                                    final Class enumClass,
						    final T def)
		throws ParseException {

		if (o.get(key) != null) {
			return getEnum(o, key, enumClass);
		}
		
		return def;
	}


	/**
	 * Gets a string member of a JSON object as {@code java.net.URI}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static URI getURI(final JSONObject o, final String key)
		throws ParseException {

		try {
			return new URI(getGeneric(o, key, String.class));

		} catch (URISyntaxException e) {

			throw new ParseException(e.getMessage(), e);
		}
	}


	/**
	 * Gets a string member of a JSON object as {@code java.net.URI}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static URI getURI(final JSONObject o, final String key, final URI def)
		throws ParseException {

		if (o.get(key) != null) {
			return getURI(o, key);
		}
		
		return def;
	}
	
	
	/**
	 * Gets a string member of a JSON object as {@code java.net.URL}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static URL getURL(final JSONObject o, final String key)
		throws ParseException {
		
		try {
			return new URL(getGeneric(o, key, String.class));
			
		} catch (MalformedURLException e) {
		
			throw new ParseException(e.getMessage(), e);
		}
	}
	
	
	/**
	 * Gets a string member of a JSON object as {@code java.net.URL}.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static URL getURL(final JSONObject o, final String key, final URL def)
		throws ParseException {
		
		if (o.get(key) != null) {
			return getURL(o, key);
		}
		
		return def;
	}
	
	
	/**
	 * Gets a JSON array member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static JSONArray getJSONArray(final JSONObject o, final String key)
		throws ParseException {
		
		List list = getGeneric(o, key, List.class);
		JSONArray jsonArray = new JSONArray();
		jsonArray.addAll(list);
		return jsonArray;
	}
	
	
	/**
	 * Gets a JSON array member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static JSONArray getJSONArray(final JSONObject o, final String key, final JSONArray def)
		throws ParseException {
		
		if (o.get(key) != null) {
			return getJSONArray(o, key);
		}
		
		return def;
	}


	/**
	 * Gets a list member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	@SuppressWarnings("unchecked")
	public static List getList(final JSONObject o, final String key)
		throws ParseException {
		
		return getGeneric(o, key, List.class);
	}


	/**
	 * Gets a list member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static List getList(final JSONObject o, final String key, final List def)
		throws ParseException {
		
		if (o.get(key) != null) {
			return getList(o, key);
		}
		
		return def;
	}


	/**
	 * Gets a string array member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static String[] getStringArray(final JSONObject o, final String key)
		throws ParseException {

		List list = getList(o, key);

		try {
			return list.toArray(new String[0]);

		} catch (ArrayStoreException e) {

			throw new ParseException("JSON object member with key " + key + " is not an array of strings");
		}
	}


	/**
	 * Gets a string array member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static String[] getStringArray(final JSONObject o, final String key, final String[] def)
		throws ParseException {

		if (o.get(key) != null) {
			return getStringArray(o, key);
		}
		
		return def;
	}


	/**
	 * Gets a string list member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static List getStringList(final JSONObject o, final String key)
		throws ParseException {

		return Arrays.asList(getStringArray(o, key));
	}


	/**
	 * Gets a string list member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static List getStringList(final JSONObject o, final String key, final List def)
		throws ParseException {

		if (o.get(key) != null) {
			return getStringList(o, key);
		}
		
		return def;
	}


	/**
	 * Gets a string array member of a JSON object as a string set.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static Set getStringSet(final JSONObject o, final String key)
		throws ParseException {

		List list = getList(o, key);

		Set set = new HashSet<>();

		for (Object item: list) {

			try {
				set.add((String)item);

			} catch (Exception e) {

				throw new ParseException("JSON object member with key " + key + " is not an array of strings");
			}

		}

		return set;
	}


	/**
	 * Gets a string array member of a JSON object as a string set.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static Set getStringSet(final JSONObject o, final String key, final Set def)
		throws ParseException {

		if (o.get(key) != null) {
			return getStringSet(o, key);
		}
		
		return def;
	}
	
	
	/**
	 * Gets a JSON object member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is missing, {@code null} or not
	 *                        of the expected type.
	 */
	public static JSONObject getJSONObject(final JSONObject o, final String key)
		throws ParseException {
		
		@SuppressWarnings("unchecked")
		Map mapObject = getGeneric(o, key, Map.class);
		return new JSONObject(mapObject);
	}
	
	
	/**
	 * Gets a JSON object member of a JSON object.
	 *
	 * @param o   The JSON object. Must not be {@code null}.
	 * @param key The JSON object member key. Must not be {@code null}.
	 * @param def The default value to return if the key is not present or
	 *            the value is {@code null}. May be {@code null}.
	 *
	 * @return The member value.
	 *
	 * @throws ParseException If the value is not of the expected type.
	 */
	public static JSONObject getJSONObject(final JSONObject o, final String key, final JSONObject def)
		throws ParseException {
		
		if (o.get(key) != null) {
			return getJSONObject(o, key);
		}
		
		return def;
	}
	
	
	/**
	 * Returns the JSON object representation of the specified JWT claims
	 * set.
	 *
	 * @param jwtClaimsSet The JWT claims set, {@code null} if not
	 *                     specified.
	 *
	 * @return The JSON object, {@code null} if not specified.
	 */
	public static JSONObject toJSONObject(final JWTClaimsSet jwtClaimsSet) {
		
		if (jwtClaimsSet == null) {
			return null;
		}
		
		if (jwtClaimsSet.getClaims().isEmpty()) {
			return new JSONObject();
		}
		
		// Serialise and parse is the safest method
		final String json = jwtClaimsSet.toString();
		
		try {
			return parse(json);
		} catch (ParseException e) {
			// Should never happen
			return null;
		}
	}
	
	
	/**
	 * Returns the JSON object representation of the specified JWK set.
	 *
	 * @param jwkSet The JWK set, {@code null} if not specified.
	 *
	 * @return The JSON object, {@code null} if not specified.
	 */
	public static JSONObject toJSONObject(final JWKSet jwkSet) {
		
		if (jwkSet == null) {
			return null;
		}
		
		// Serialise and parse is the safest method
		final String json = jwkSet.toString(false);
		
		try {
			return parse(json);
		} catch (ParseException e) {
			// Should never happen
			return null;
		}
	}
	

	/**
	 * Prevents public instantiation.
	 */
	private JSONObjectUtils() {}
}

    

    

    

            

    

            



    
    






    
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