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/*
 * ====================================================================
 * Project:     openMDX/Core, http://www.openmdx.org/
 * Description: JSONArray
 * Owner:       OMEX AG, Switzerland, http://www.omex.ch
 * ====================================================================
 *
 * This software is published under the BSD license as listed below.
 * 
 * Copyright (c) 2014, OMEX AG, Switzerland
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the following
 * conditions are met:
 * 
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * 
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in
 *   the documentation and/or other materials provided with the
 *   distribution.
 * 
 * * Neither the name of the openMDX team nor the names of its
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * ------------------
 * 
 * Copyright 2006 Envoi Solutions LLC
 * 
 * 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 org.openmdx.base.json.stream;

import java.io.IOException;
import java.io.Serializable;
import java.io.Writer;
import java.util.ArrayList;
import java.util.Collection;
import java.util.ListIterator;
import java.util.Map;

/**
 * A JSONArray is an ordered sequence of values. Its external text form is a
 * string wrapped in square brackets with commas separating the values. The
 * internal form is an object having get and opt
 * methods for accessing the values by index, and put methods for
 * adding or replacing values. The values can be any of these types:
 * Boolean, JSONArray, JSONObject,
 * Number, String, or the
 * JSONObject.NULL object.
 * 

* The constructor can convert a JSON text into a Java object. The * toString method converts to JSON text. *

* A get method returns a value if one can be found, and throws an * exception if one cannot be found. An opt method returns a * default value instead of throwing an exception, and so is useful for * obtaining optional values. *

* The generic get() and opt() methods return an * object which you can cast or query for type. There are also typed * get and opt methods that do type checking and type * coersion for you. *

* The texts produced by the toString methods strictly conform to * JSON syntax rules. The constructors are more forgiving in the texts they will * accept: *

    *
  • An extra , (comma) may appear just * before the closing bracket.
  • *
  • The null value will be inserted when there * is , (comma) elision.
  • *
  • Strings may be quoted with ' (single * quote).
  • *
  • Strings do not need to be quoted at all if they do not begin with a quote * or single quote, and if they do not contain leading or trailing spaces, * and if they do not contain any of these characters: * { } [ ] / \ : , = ; # and if they do not look like numbers * and if they are not the reserved words true, * false, or null.
  • *
  • Values can be separated by ; (semicolon) as * well as by , (comma).
  • *
  • Numbers may have the 0- (octal) or * 0x- (hex) prefix.
  • *
  • Comments written in the slashshlash, slashstar, and hash conventions * will be ignored.
  • *
* @author JSON.org * @version 2 */ @SuppressWarnings("serial") public class JSONArray implements Serializable { /** * The arrayList where the JSONArray's properties are kept. */ private ArrayList myArrayList; /** * Construct an empty JSONArray. */ public JSONArray() { this.myArrayList = new ArrayList(); } /** * Construct an empty JSONArray with a given capacity. */ public JSONArray(int capacity) { this.myArrayList = new ArrayList(capacity); } /** * Construct a JSONArray from a JSONTokener. * @param x A JSONTokener * @throws JSONException If there is a syntax error. */ public JSONArray(JSONTokener x) throws JSONException { this(); if (x.nextClean() != '[') { throw x.syntaxError("A JSONArray text must start with '['"); } if (x.nextClean() == ']') { return; } x.back(); for (;;) { if (x.nextClean() == ',') { x.back(); this.myArrayList.add(null); } else { x.back(); this.myArrayList.add(x.nextValue()); } switch (x.nextClean()) { case ';': case ',': if (x.nextClean() == ']') { return; } x.back(); break; case ']': return; default: throw x.syntaxError("Expected a ',' or ']'"); } } } /** * Construct a JSONArray from a source sJSON text. * @param string A string that begins with * [ (left bracket) * and ends with ] (right bracket). * @throws JSONException If there is a syntax error. */ public JSONArray(String string) throws JSONException { this(new JSONTokener(string)); } /** * Construct a JSONArray from a Collection. * @param collection A Collection. */ @SuppressWarnings("unchecked") public JSONArray(Collection collection) { this.myArrayList = (collection == null) ? new ArrayList() : new ArrayList(collection); // ensure a pure hierarchy of JSONObjects and JSONArrays for (ListIterator iter = myArrayList.listIterator(); iter.hasNext();) { Object e = iter.next(); if (e instanceof Collection) { iter.set(new JSONArray((Collection) e)); } if (e instanceof Map) { iter.set(new JSONObject((Map) e)); } } } /** * Get the object value associated with an index. * @param index * The index must be between 0 and length() - 1. * @return An object value. * @throws JSONException If there is no value for the index. */ public Object get(int index) throws JSONException { Object o = opt(index); if (o == null) { throw new JSONException("JSONArray[" + index + "] not found."); } return o; } /** * Get the boolean value associated with an index. * The string values "true" and "false" are converted to boolean. * * @param index The index must be between 0 and length() - 1. * @return The truth. * @throws JSONException If there is no value for the index or if the * value is not convertable to boolean. */ public boolean getBoolean(int index) throws JSONException { Object o = get(index); if (o.equals(Boolean.FALSE) || (o instanceof String && ((String)o).equalsIgnoreCase("false"))) { return false; } else if (o.equals(Boolean.TRUE) || (o instanceof String && ((String)o).equalsIgnoreCase("true"))) { return true; } throw new JSONException("JSONArray[" + index + "] is not a Boolean."); } /** * Get the double value associated with an index. * * @param index The index must be between 0 and length() - 1. * @return The value. * @throws JSONException If the key is not found or if the value cannot * be converted to a number. */ public double getDouble(int index) throws JSONException { Object o = get(index); try { return o instanceof Number ? ((Number)o).doubleValue() : Double.valueOf((String)o).doubleValue(); } catch (Exception e) { throw new JSONException("JSONArray[" + index + "] is not a number."); } } /** * Get the int value associated with an index. * * @param index The index must be between 0 and length() - 1. * @return The value. * @throws JSONException If the key is not found or if the value cannot * be converted to a number. * if the value cannot be converted to a number. */ public int getInt(int index) throws JSONException { Object o = get(index); return o instanceof Number ? ((Number)o).intValue() : (int)getDouble(index); } /** * Get the JSONArray associated with an index. * @param index The index must be between 0 and length() - 1. * @return A JSONArray value. * @throws JSONException If there is no value for the index. or if the * value is not a JSONArray */ public JSONArray getJSONArray(int index) throws JSONException { Object o = get(index); if (o instanceof JSONArray) { return (JSONArray)o; } throw new JSONException("JSONArray[" + index + "] is not a JSONArray."); } /** * Get the JSONObject associated with an index. * @param index subscript * @return A JSONObject value. * @throws JSONException If there is no value for the index or if the * value is not a JSONObject */ public JSONObject getJSONObject(int index) throws JSONException { Object o = get(index); if (o instanceof JSONObject) { return (JSONObject)o; } throw new JSONException("JSONArray[" + index + "] is not a JSONObject."); } /** * Get the long value associated with an index. * * @param index The index must be between 0 and length() - 1. * @return The value. * @throws JSONException If the key is not found or if the value cannot * be converted to a number. */ public long getLong(int index) throws JSONException { Object o = get(index); return o instanceof Number ? ((Number)o).longValue() : (long)getDouble(index); } /** * Get the string associated with an index. * @param index The index must be between 0 and length() - 1. * @return A string value. * @throws JSONException If there is no value for the index. */ public String getString(int index) throws JSONException { return get(index).toString(); } /** * Determine if the value is null. * @param index The index must be between 0 and length() - 1. * @return true if the value at the index is null, or if there is no value. */ public boolean isNull(int index) { return JSONObject.NULL.equals(opt(index)); } /** * Make a string from the contents of this JSONArray. The * separator string is inserted between each element. * Warning: This method assumes that the data structure is acyclical. * @param separator A string that will be inserted between the elements. * @return a string. * @throws JSONException If the array contains an invalid number. */ public String join(String separator) throws JSONException { int len = length(); StringBuilder sb = new StringBuilder(); for (int i = 0; i < len; i += 1) { if (i > 0) { sb.append(separator); } sb.append(JSONObject.valueToString(this.myArrayList.get(i))); } return sb.toString(); } /** * Get the number of elements in the JSONArray, included nulls. * * @return The length (or size). */ public int length() { return this.myArrayList.size(); } /** * Get the optional object value associated with an index. * @param index The index must be between 0 and length() - 1. * @return An object value, or null if there is no * object at that index. */ public Object opt(int index) { return (index < 0 || index >= length()) ? null : this.myArrayList.get(index); } /** * Get the optional boolean value associated with an index. * It returns false if there is no value at that index, * or if the value is not Boolean.TRUE or the String "true". * * @param index The index must be between 0 and length() - 1. * @return The truth. */ public boolean optBoolean(int index) { return optBoolean(index, false); } /** * Get the optional boolean value associated with an index. * It returns the defaultValue if there is no value at that index or if * it is not a Boolean or the String "true" or "false" (case insensitive). * * @param index The index must be between 0 and length() - 1. * @param defaultValue A boolean default. * @return The truth. */ public boolean optBoolean(int index, boolean defaultValue) { try { return getBoolean(index); } catch (Exception e) { return defaultValue; } } /** * Get the optional double value associated with an index. * NaN is returned if there is no value for the index, * or if the value is not a number and cannot be converted to a number. * * @param index The index must be between 0 and length() - 1. * @return The value. */ public double optDouble(int index) { return optDouble(index, Double.NaN); } /** * Get the optional double value associated with an index. * The defaultValue is returned if there is no value for the index, * or if the value is not a number and cannot be converted to a number. * * @param index subscript * @param defaultValue The default value. * @return The value. */ public double optDouble(int index, double defaultValue) { try { return getDouble(index); } catch (Exception e) { return defaultValue; } } /** * Get the optional int value associated with an index. * Zero is returned if there is no value for the index, * or if the value is not a number and cannot be converted to a number. * * @param index The index must be between 0 and length() - 1. * @return The value. */ public int optInt(int index) { return optInt(index, 0); } /** * Get the optional int value associated with an index. * The defaultValue is returned if there is no value for the index, * or if the value is not a number and cannot be converted to a number. * @param index The index must be between 0 and length() - 1. * @param defaultValue The default value. * @return The value. */ public int optInt(int index, int defaultValue) { try { return getInt(index); } catch (Exception e) { return defaultValue; } } /** * Get the optional JSONArray associated with an index. * @param index subscript * @return A JSONArray value, or null if the index has no value, * or if the value is not a JSONArray. */ public JSONArray optJSONArray(int index) { Object o = opt(index); return o instanceof JSONArray ? (JSONArray)o : null; } /** * Get the optional JSONObject associated with an index. * Null is returned if the key is not found, or null if the index has * no value, or if the value is not a JSONObject. * * @param index The index must be between 0 and length() - 1. * @return A JSONObject value. */ public JSONObject optJSONObject(int index) { Object o = opt(index); return o instanceof JSONObject ? (JSONObject)o : null; } /** * Get the optional long value associated with an index. * Zero is returned if there is no value for the index, * or if the value is not a number and cannot be converted to a number. * * @param index The index must be between 0 and length() - 1. * @return The value. */ public long optLong(int index) { return optLong(index, 0); } /** * Get the optional long value associated with an index. * The defaultValue is returned if there is no value for the index, * or if the value is not a number and cannot be converted to a number. * @param index The index must be between 0 and length() - 1. * @param defaultValue The default value. * @return The value. */ public long optLong(int index, long defaultValue) { try { return getLong(index); } catch (Exception e) { return defaultValue; } } /** * Get the optional string value associated with an index. It returns an * empty string if there is no value at that index. If the value * is not a string and is not null, then it is coverted to a string. * * @param index The index must be between 0 and length() - 1. * @return A String value. */ public String optString(int index) { return optString(index, ""); } /** * Get the optional string associated with an index. * The defaultValue is returned if the key is not found. * * @param index The index must be between 0 and length() - 1. * @param defaultValue The default value. * @return A String value. */ public String optString(int index, String defaultValue) { Object o = opt(index); return o != null ? o.toString() : defaultValue; } /** * Append a boolean value. This increases the array's length by one. * * @param value A boolean value. * @return this. */ public JSONArray put(boolean value) { put(value ? Boolean.TRUE : Boolean.FALSE); return this; } /** * Put a value in the JSONArray, where the value will be a * JSONArray which is produced from a Collection. * @param value A Collection value. * @return this. */ public JSONArray put(Collection value) { put(new JSONArray(value)); return this; } /** * Append a double value. This increases the array's length by one. * * @param value A double value. * @throws JSONException if the value is not finite. * @return this. */ public JSONArray put(double value) throws JSONException { Double d = new Double(value); JSONObject.testValidity(d); put(d); return this; } /** * Append an int value. This increases the array's length by one. * * @param value An int value. * @return this. */ public JSONArray put(int value) { put(Integer.valueOf(value)); return this; } /** * Append an long value. This increases the array's length by one. * * @param value A long value. * @return this. */ public JSONArray put(long value) { put(new Long(value)); return this; } /** * Put a value in the JSONArray, where the value will be a * JSONObject which is produced from a Map. * @param value A Map value. * @return this. */ public JSONArray put(Map value) { put(new JSONObject(value)); return this; } /** * Append an object value. This increases the array's length by one. * @param value An object value. The value should be a * Boolean, Double, Integer, JSONArray, JSONObject, Long, or String, or the * JSONObject.NULL object. * @return this. */ public JSONArray put(Object value) { this.myArrayList.add(value); return this; } public JSONArray remove(Object value) { this.myArrayList.remove(value); return this; } /** * Put or replace a boolean value in the JSONArray. If the index is greater * than the length of the JSONArray, then null elements will be added as * necessary to pad it out. * @param index The subscript. * @param value A boolean value. * @return this. * @throws JSONException If the index is negative. */ public JSONArray put(int index, boolean value) throws JSONException { put(index, value ? Boolean.TRUE : Boolean.FALSE); return this; } /** * Put a value in the JSONArray, where the value will be a * JSONArray which is produced from a Collection. * @param index The subscript. * @param value A Collection value. * @return this. * @throws JSONException If the index is negative or if the value is * not finite. */ public JSONArray put(int index, Collection value) throws JSONException { put(index, new JSONArray(value)); return this; } /** * Put or replace a double value. If the index is greater than the length of * the JSONArray, then null elements will be added as necessary to pad * it out. * @param index The subscript. * @param value A double value. * @return this. * @throws JSONException If the index is negative or if the value is * not finite. */ public JSONArray put(int index, double value) throws JSONException { put(index, new Double(value)); return this; } /** * Put or replace an int value. If the index is greater than the length of * the JSONArray, then null elements will be added as necessary to pad * it out. * @param index The subscript. * @param value An int value. * @return this. * @throws JSONException If the index is negative. */ public JSONArray put(int index, int value) throws JSONException { put(index, Integer.valueOf(value)); return this; } /** * Put or replace a long value. If the index is greater than the length of * the JSONArray, then null elements will be added as necessary to pad * it out. * @param index The subscript. * @param value A long value. * @return this. * @throws JSONException If the index is negative. */ public JSONArray put(int index, long value) throws JSONException { put(index, new Long(value)); return this; } /** * Put a value in the JSONArray, where the value will be a * JSONObject which is produced from a Map. * @param index The subscript. * @param value The Map value. * @return this. * @throws JSONException If the index is negative or if the the value is * an invalid number. */ public JSONArray put(int index, Map value) throws JSONException { put(index, new JSONObject(value)); return this; } /** * Put or replace an object value in the JSONArray. If the index is greater * than the length of the JSONArray, then null elements will be added as * necessary to pad it out. * @param index The subscript. * @param value The value to put into the array. The value should be a * Boolean, Double, Integer, JSONArray, JSONObject, Long, or String, or the * JSONObject.NULL object. * @return this. * @throws JSONException If the index is negative or if the the value is * an invalid number. */ public JSONArray put(int index, Object value) throws JSONException { JSONObject.testValidity(value); if (index < 0) { throw new JSONException("JSONArray[" + index + "] not found."); } if (index < length()) { this.myArrayList.set(index, value); } else { while (index != length()) { put(JSONObject.NULL); } put(value); } return this; } /** * Produce a JSONObject by combining a JSONArray of names with the values * of this JSONArray. * @param names A JSONArray containing a list of key strings. These will be * paired with the values. * @return A JSONObject, or null if there are no names or if this JSONArray * has no values. * @throws JSONException If any of the names are null. */ public JSONObject toJSONObject(JSONArray names) throws JSONException { if (names == null || names.length() == 0 || length() == 0) { return null; } JSONObject jo = new JSONObject(); for (int i = 0; i < names.length(); i += 1) { jo.put(names.getString(i), this.opt(i)); } return jo; } /** * Make a JSON text of this JSONArray. For compactness, no * unnecessary whitespace is added. If it is not possible to produce a * syntactically correct JSON text then null will be returned instead. This * could occur if the array contains an invalid number. *

* Warning: This method assumes that the data structure is acyclical. * * @return a printable, displayable, transmittable * representation of the array. */ public String toString() { try { return '[' + join(",") + ']'; } catch (Exception e) { return null; } } /** * Make a prettyprinted JSON text of this JSONArray. * Warning: This method assumes that the data structure is acyclical. * @param indentFactor The number of spaces to add to each level of * indentation. * @return a printable, displayable, transmittable * representation of the object, beginning * with [ (left bracket) and ending * with ] (right bracket). * @throws JSONException */ public String toString(int indentFactor) throws JSONException { return toString(indentFactor, 0); } /** * Make a prettyprinted JSON text of this JSONArray. * Warning: This method assumes that the data structure is acyclical. * @param indentFactor The number of spaces to add to each level of * indentation. * @param indent The indention of the top level. * @return a printable, displayable, transmittable * representation of the array. * @throws JSONException */ String toString(int indentFactor, int indent) throws JSONException { int len = length(); if (len == 0) { return "[]"; } int i; StringBuilder sb = new StringBuilder("["); if (len == 1) { sb.append(JSONObject.valueToString(this.myArrayList.get(0), indentFactor, indent)); } else { int newindent = indent + indentFactor; sb.append('\n'); for (i = 0; i < len; i += 1) { if (i > 0) { sb.append(",\n"); } for (int j = 0; j < newindent; j += 1) { sb.append(' '); } sb.append(JSONObject.valueToString(this.myArrayList.get(i), indentFactor, newindent)); } sb.append('\n'); for (i = 0; i < indent; i += 1) { sb.append(' '); } } sb.append(']'); return sb.toString(); } @Override public int hashCode() { return myArrayList.hashCode(); } @Override public boolean equals(Object obj) { if (obj instanceof JSONArray) { return myArrayList.equals(((JSONArray)obj).myArrayList); } else { return false; } } /** * Write the contents of the JSONArray as JSON text to a writer. * For compactness, no whitespace is added. *

* Warning: This method assumes that the data structure is acyclical. * * @return The writer. * @throws JSONException */ public Writer write(Writer writer) throws JSONException { try { boolean b = false; int len = length(); writer.write('['); for (int i = 0; i < len; i += 1) { if (b) { writer.write(','); } Object v = this.myArrayList.get(i); if (v instanceof JSONObject) { ((JSONObject)v).write(writer); } else if (v instanceof JSONArray) { ((JSONArray)v).write(writer); } else { writer.write(JSONObject.valueToString(v)); } b = true; } writer.write(']'); return writer; } catch (IOException e) { throw new JSONException(e); } } }