colonymech / docs / www / colonyscout / internal / includes / uploadify / com / adobe / serialization / json / JSONDecoder.as @ f59acf11
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/* |
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Copyright (c) 2008, Adobe Systems Incorporated |
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All rights reserved. |
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|
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Redistribution and use in source and binary forms, with or without |
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modification, are permitted provided that the following conditions are |
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met: |
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|
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* Redistributions of source code must retain the above copyright notice, |
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this list of conditions and the following disclaimer. |
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|
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* Redistributions in binary form must reproduce the above copyright |
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notice, this list of conditions and the following disclaimer in the |
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documentation and/or other materials provided with the distribution. |
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|
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* Neither the name of Adobe Systems Incorporated nor the names of its |
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contributors may be used to endorse or promote products derived from |
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this software without specific prior written permission. |
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|
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS |
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IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
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THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
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PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
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CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
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EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
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PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
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PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
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LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
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NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
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SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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*/ |
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|
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package com.adobe.serialization.json { |
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|
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public class JSONDecoder { |
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|
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/** The value that will get parsed from the JSON string */ |
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private var value:*; |
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|
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/** The tokenizer designated to read the JSON string */ |
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private var tokenizer:JSONTokenizer; |
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|
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/** The current token from the tokenizer */ |
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private var token:JSONToken; |
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|
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/** |
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* Constructs a new JSONDecoder to parse a JSON string |
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* into a native object. |
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* |
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* @param s The JSON string to be converted |
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* into a native object |
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* @langversion ActionScript 3.0 |
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* @playerversion Flash 9.0 |
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* @tiptext |
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*/ |
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public function JSONDecoder( s:String ) { |
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|
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tokenizer = new JSONTokenizer( s ); |
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|
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nextToken(); |
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value = parseValue(); |
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} |
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|
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/** |
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* Gets the internal object that was created by parsing |
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* the JSON string passed to the constructor. |
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* |
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* @return The internal object representation of the JSON |
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* string that was passed to the constructor |
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* @langversion ActionScript 3.0 |
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* @playerversion Flash 9.0 |
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* @tiptext |
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*/ |
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public function getValue():* { |
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return value; |
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} |
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|
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/** |
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* Returns the next token from the tokenzier reading |
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* the JSON string |
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*/ |
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private function nextToken():JSONToken { |
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return token = tokenizer.getNextToken(); |
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} |
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|
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/** |
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* Attempt to parse an array |
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*/ |
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private function parseArray():Array { |
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// create an array internally that we're going to attempt |
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// to parse from the tokenizer |
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var a:Array = new Array(); |
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|
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// grab the next token from the tokenizer to move |
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// past the opening [ |
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nextToken(); |
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|
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// check to see if we have an empty array |
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if ( token.type == JSONTokenType.RIGHT_BRACKET ) { |
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// we're done reading the array, so return it |
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return a; |
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} |
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|
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// deal with elements of the array, and use an "infinite" |
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// loop because we could have any amount of elements |
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while ( true ) { |
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// read in the value and add it to the array |
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a.push ( parseValue() ); |
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|
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// after the value there should be a ] or a , |
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nextToken(); |
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|
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if ( token.type == JSONTokenType.RIGHT_BRACKET ) { |
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// we're done reading the array, so return it |
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return a; |
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} else if ( token.type == JSONTokenType.COMMA ) { |
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// move past the comma and read another value |
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nextToken(); |
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} else { |
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tokenizer.parseError( "Expecting ] or , but found " + token.value ); |
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} |
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} |
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return null; |
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} |
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|
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/** |
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* Attempt to parse an object |
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*/ |
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private function parseObject():Object { |
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// create the object internally that we're going to |
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// attempt to parse from the tokenizer |
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var o:Object = new Object(); |
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|
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// store the string part of an object member so |
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// that we can assign it a value in the object |
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var key:String |
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|
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// grab the next token from the tokenizer |
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nextToken(); |
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|
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// check to see if we have an empty object |
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if ( token.type == JSONTokenType.RIGHT_BRACE ) { |
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// we're done reading the object, so return it |
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return o; |
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} |
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|
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// deal with members of the object, and use an "infinite" |
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// loop because we could have any amount of members |
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while ( true ) { |
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|
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if ( token.type == JSONTokenType.STRING ) { |
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// the string value we read is the key for the object |
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key = String( token.value ); |
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|
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// move past the string to see what's next |
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nextToken(); |
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|
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// after the string there should be a : |
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if ( token.type == JSONTokenType.COLON ) { |
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|
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// move past the : and read/assign a value for the key |
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nextToken(); |
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o[key] = parseValue(); |
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|
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// move past the value to see what's next |
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nextToken(); |
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|
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// after the value there's either a } or a , |
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if ( token.type == JSONTokenType.RIGHT_BRACE ) { |
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// // we're done reading the object, so return it |
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return o; |
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|
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} else if ( token.type == JSONTokenType.COMMA ) { |
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// skip past the comma and read another member |
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nextToken(); |
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} else { |
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tokenizer.parseError( "Expecting } or , but found " + token.value ); |
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} |
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} else { |
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tokenizer.parseError( "Expecting : but found " + token.value ); |
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} |
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} else { |
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tokenizer.parseError( "Expecting string but found " + token.value ); |
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} |
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} |
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return null; |
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} |
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|
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/** |
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* Attempt to parse a value |
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*/ |
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private function parseValue():Object |
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{ |
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// Catch errors when the input stream ends abruptly |
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if ( token == null ) |
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{ |
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tokenizer.parseError( "Unexpected end of input" ); |
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} |
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|
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switch ( token.type ) { |
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case JSONTokenType.LEFT_BRACE: |
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return parseObject(); |
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|
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case JSONTokenType.LEFT_BRACKET: |
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return parseArray(); |
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|
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case JSONTokenType.STRING: |
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case JSONTokenType.NUMBER: |
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case JSONTokenType.TRUE: |
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case JSONTokenType.FALSE: |
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case JSONTokenType.NULL: |
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return token.value; |
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|
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default: |
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tokenizer.parseError( "Unexpected " + token.value ); |
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|
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} |
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return null; |
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} |
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} |
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} |