| /* |
| * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package jdk.nashorn.internal.parser; |
| |
| import static jdk.nashorn.internal.parser.TokenType.COLON; |
| import static jdk.nashorn.internal.parser.TokenType.COMMARIGHT; |
| import static jdk.nashorn.internal.parser.TokenType.EOF; |
| import static jdk.nashorn.internal.parser.TokenType.ESCSTRING; |
| import static jdk.nashorn.internal.parser.TokenType.RBRACE; |
| import static jdk.nashorn.internal.parser.TokenType.RBRACKET; |
| import static jdk.nashorn.internal.parser.TokenType.STRING; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| import jdk.nashorn.internal.ir.Expression; |
| import jdk.nashorn.internal.ir.LiteralNode; |
| import jdk.nashorn.internal.ir.Node; |
| import jdk.nashorn.internal.ir.ObjectNode; |
| import jdk.nashorn.internal.ir.PropertyNode; |
| import jdk.nashorn.internal.ir.UnaryNode; |
| import jdk.nashorn.internal.runtime.ErrorManager; |
| import jdk.nashorn.internal.runtime.Source; |
| |
| /** |
| * Parses JSON text and returns the corresponding IR node. This is derived from the objectLiteral production of the main parser. |
| * |
| * See: 15.12.1.2 The JSON Syntactic Grammar |
| */ |
| public class JSONParser extends AbstractParser { |
| |
| /** |
| * Constructor |
| * @param source the source |
| * @param errors the error manager |
| */ |
| public JSONParser(final Source source, final ErrorManager errors) { |
| super(source, errors, false, 0); |
| } |
| |
| /** |
| * Implementation of the Quote(value) operation as defined in the ECMA script spec |
| * It wraps a String value in double quotes and escapes characters within in |
| * |
| * @param value string to quote |
| * |
| * @return quoted and escaped string |
| */ |
| public static String quote(final String value) { |
| |
| final StringBuilder product = new StringBuilder(); |
| |
| product.append("\""); |
| |
| for (final char ch : value.toCharArray()) { |
| // TODO: should use a table? |
| switch (ch) { |
| case '\\': |
| product.append("\\\\"); |
| break; |
| case '"': |
| product.append("\\\""); |
| break; |
| case '\b': |
| product.append("\\b"); |
| break; |
| case '\f': |
| product.append("\\f"); |
| break; |
| case '\n': |
| product.append("\\n"); |
| break; |
| case '\r': |
| product.append("\\r"); |
| break; |
| case '\t': |
| product.append("\\t"); |
| break; |
| default: |
| if (ch < ' ') { |
| product.append(Lexer.unicodeEscape(ch)); |
| break; |
| } |
| |
| product.append(ch); |
| break; |
| } |
| } |
| |
| product.append("\""); |
| |
| return product.toString(); |
| } |
| |
| /** |
| * Public parsed method - start lexing a new token stream for |
| * a JSON script |
| * |
| * @return the JSON literal |
| */ |
| public Node parse() { |
| stream = new TokenStream(); |
| |
| lexer = new Lexer(source, stream) { |
| |
| @Override |
| protected boolean skipComments() { |
| return false; |
| } |
| |
| @Override |
| protected boolean isStringDelimiter(final char ch) { |
| return ch == '\"'; |
| } |
| |
| // ECMA 15.12.1.1 The JSON Lexical Grammar - JSONWhiteSpace |
| @Override |
| protected boolean isWhitespace(final char ch) { |
| return Lexer.isJsonWhitespace(ch); |
| } |
| |
| @Override |
| protected boolean isEOL(final char ch) { |
| return Lexer.isJsonEOL(ch); |
| } |
| |
| // ECMA 15.12.1.1 The JSON Lexical Grammar - JSONNumber |
| @Override |
| protected void scanNumber() { |
| // Record beginning of number. |
| final int startPosition = position; |
| // Assume value is a decimal. |
| TokenType valueType = TokenType.DECIMAL; |
| |
| // floating point can't start with a "." with no leading digit before |
| if (ch0 == '.') { |
| error(Lexer.message("json.invalid.number"), STRING, position, limit); |
| } |
| |
| // First digit of number. |
| final int digit = convertDigit(ch0, 10); |
| |
| // skip first digit |
| skip(1); |
| |
| if (digit != 0) { |
| // Skip over remaining digits. |
| while (convertDigit(ch0, 10) != -1) { |
| skip(1); |
| } |
| } |
| |
| if (ch0 == '.' || ch0 == 'E' || ch0 == 'e') { |
| // Must be a double. |
| if (ch0 == '.') { |
| // Skip period. |
| skip(1); |
| |
| boolean mantissa = false; |
| // Skip mantissa. |
| while (convertDigit(ch0, 10) != -1) { |
| mantissa = true; |
| skip(1); |
| } |
| |
| if (! mantissa) { |
| // no digit after "." |
| error(Lexer.message("json.invalid.number"), STRING, position, limit); |
| } |
| } |
| |
| // Detect exponent. |
| if (ch0 == 'E' || ch0 == 'e') { |
| // Skip E. |
| skip(1); |
| // Detect and skip exponent sign. |
| if (ch0 == '+' || ch0 == '-') { |
| skip(1); |
| } |
| boolean exponent = false; |
| // Skip exponent. |
| while (convertDigit(ch0, 10) != -1) { |
| exponent = true; |
| skip(1); |
| } |
| |
| if (! exponent) { |
| // no digit after "E" |
| error(Lexer.message("json.invalid.number"), STRING, position, limit); |
| } |
| } |
| |
| valueType = TokenType.FLOATING; |
| } |
| |
| // Add number token. |
| add(valueType, startPosition); |
| } |
| |
| // ECMA 15.12.1.1 The JSON Lexical Grammar - JSONEscapeCharacter |
| @Override |
| protected boolean isEscapeCharacter(final char ch) { |
| switch (ch) { |
| case '"': |
| case '/': |
| case '\\': |
| case 'b': |
| case 'f': |
| case 'n': |
| case 'r': |
| case 't': |
| // could be unicode escape |
| case 'u': |
| return true; |
| default: |
| return false; |
| } |
| } |
| }; |
| |
| k = -1; |
| |
| next(); |
| |
| final Node resultNode = jsonLiteral(); |
| expect(EOF); |
| |
| return resultNode; |
| } |
| |
| @SuppressWarnings("fallthrough") |
| private LiteralNode<?> getStringLiteral() { |
| final LiteralNode<?> literal = getLiteral(); |
| final String str = (String)literal.getValue(); |
| |
| for (int i = 0; i < str.length(); i++) { |
| final char ch = str.charAt(i); |
| switch (ch) { |
| default: |
| if (ch > 0x001f) { |
| break; |
| } |
| case '"': |
| case '\\': |
| throw error(AbstractParser.message("unexpected.token", str)); |
| } |
| } |
| |
| return literal; |
| } |
| |
| /** |
| * Parse a JSON literal from the token stream |
| * @return the JSON literal as a Node |
| */ |
| private Expression jsonLiteral() { |
| final long literalToken = token; |
| |
| switch (type) { |
| case STRING: |
| return getStringLiteral(); |
| case ESCSTRING: |
| case DECIMAL: |
| case FLOATING: |
| return getLiteral(); |
| case FALSE: |
| next(); |
| return LiteralNode.newInstance(literalToken, finish, false); |
| case TRUE: |
| next(); |
| return LiteralNode.newInstance(literalToken, finish, true); |
| case NULL: |
| next(); |
| return LiteralNode.newInstance(literalToken, finish); |
| case LBRACKET: |
| return arrayLiteral(); |
| case LBRACE: |
| return objectLiteral(); |
| /* |
| * A.8.1 JSON Lexical Grammar |
| * |
| * JSONNumber :: See 15.12.1.1 |
| * -opt DecimalIntegerLiteral JSONFractionopt ExponentPartopt |
| */ |
| case SUB: |
| next(); |
| |
| final long realToken = token; |
| final Object value = getValue(); |
| |
| if (value instanceof Number) { |
| next(); |
| return new UnaryNode(literalToken, LiteralNode.newInstance(realToken, finish, (Number)value)); |
| } |
| |
| throw error(AbstractParser.message("expected", "number", type.getNameOrType())); |
| default: |
| break; |
| } |
| |
| throw error(AbstractParser.message("expected", "json literal", type.getNameOrType())); |
| } |
| |
| /** |
| * Parse an array literal from the token stream |
| * @return the array literal as a Node |
| */ |
| private LiteralNode<Expression[]> arrayLiteral() { |
| // Unlike JavaScript array literals, elison is not permitted in JSON. |
| |
| // Capture LBRACKET token. |
| final long arrayToken = token; |
| // LBRACKET tested in caller. |
| next(); |
| |
| LiteralNode<Expression[]> result = null; |
| // Prepare to accummulating elements. |
| final List<Expression> elements = new ArrayList<>(); |
| |
| loop: |
| while (true) { |
| switch (type) { |
| case RBRACKET: |
| next(); |
| result = LiteralNode.newInstance(arrayToken, finish, elements); |
| break loop; |
| |
| case COMMARIGHT: |
| next(); |
| // check for trailing comma - not allowed in JSON |
| if (type == RBRACKET) { |
| throw error(AbstractParser.message("trailing.comma.in.json", type.getNameOrType())); |
| } |
| break; |
| |
| default: |
| // Add expression element. |
| elements.add(jsonLiteral()); |
| // Comma between array elements is mandatory in JSON. |
| if (type != COMMARIGHT && type != RBRACKET) { |
| throw error(AbstractParser.message("expected", ", or ]", type.getNameOrType())); |
| } |
| break; |
| } |
| } |
| |
| return result; |
| } |
| |
| /** |
| * Parse an object literal from the token stream |
| * @return the object literal as a Node |
| */ |
| private ObjectNode objectLiteral() { |
| // Capture LBRACE token. |
| final long objectToken = token; |
| // LBRACE tested in caller. |
| next(); |
| |
| // Prepare to accumulate elements. |
| final List<PropertyNode> elements = new ArrayList<>(); |
| |
| // Create a block for the object literal. |
| loop: |
| while (true) { |
| switch (type) { |
| case RBRACE: |
| next(); |
| break loop; |
| |
| case COMMARIGHT: |
| next(); |
| // check for trailing comma - not allowed in JSON |
| if (type == RBRACE) { |
| throw error(AbstractParser.message("trailing.comma.in.json", type.getNameOrType())); |
| } |
| break; |
| |
| default: |
| // Get and add the next property. |
| final PropertyNode property = propertyAssignment(); |
| elements.add(property); |
| |
| // Comma between property assigments is mandatory in JSON. |
| if (type != RBRACE && type != COMMARIGHT) { |
| throw error(AbstractParser.message("expected", ", or }", type.getNameOrType())); |
| } |
| break; |
| } |
| } |
| |
| // Construct new object literal. |
| return new ObjectNode(objectToken, finish, elements); |
| } |
| |
| /** |
| * Parse a property assignment from the token stream |
| * @return the property assignment as a Node |
| */ |
| private PropertyNode propertyAssignment() { |
| // Capture firstToken. |
| final long propertyToken = token; |
| LiteralNode<?> name = null; |
| |
| if (type == STRING) { |
| name = getStringLiteral(); |
| } else if (type == ESCSTRING) { |
| name = getLiteral(); |
| } |
| |
| if (name != null) { |
| expect(COLON); |
| final Expression value = jsonLiteral(); |
| return new PropertyNode(propertyToken, value.getFinish(), name, value, null, null); |
| } |
| |
| // Raise an error. |
| throw error(AbstractParser.message("expected", "string", type.getNameOrType())); |
| } |
| |
| } |
