| /* |
| * 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.TokenKind.LITERAL; |
| |
| import jdk.nashorn.internal.runtime.Source; |
| |
| /** |
| * Basic parse/lex unit. |
| * |
| */ |
| public class Token { |
| |
| private Token() { |
| } |
| |
| /** |
| * Create a compact form of token information. |
| * @param type Type of token. |
| * @param position Start position of the token in the source. |
| * @param length Length of the token. |
| * @return Token descriptor. |
| */ |
| public static long toDesc(final TokenType type, final int position, final int length) { |
| return (long)position << 32 | |
| (long)length << 8 | |
| type.ordinal(); |
| } |
| |
| /** |
| * Extract token position from a token descriptor. |
| * @param token Token descriptor. |
| * @return Start position of the token in the source. |
| */ |
| public static int descPosition(final long token) { |
| return (int)(token >>> 32); |
| } |
| |
| /** |
| * Normally returns the token itself, except in case of string tokens |
| * which report their position past their opening delimiter and thus |
| * need to have position and length adjusted. |
| * |
| * @param token Token descriptor. |
| * @return same or adjusted token. |
| */ |
| public static long withDelimiter(final long token) { |
| final TokenType tokenType = Token.descType(token); |
| switch(tokenType) { |
| case STRING: case ESCSTRING: case EXECSTRING: { |
| final int start = Token.descPosition(token) - 1; |
| final int len = Token.descLength(token) + 2; |
| return toDesc(tokenType, start, len); |
| } |
| default: { |
| return token; |
| } |
| } |
| } |
| |
| /** |
| * Extract token length from a token descriptor. |
| * @param token Token descriptor. |
| * @return Length of the token. |
| */ |
| public static int descLength(final long token) { |
| return (int)token >>> 8; |
| } |
| |
| /** |
| * Extract token type from a token descriptor. |
| * @param token Token descriptor. |
| * @return Type of token. |
| */ |
| public static TokenType descType(final long token) { |
| return TokenType.getValues()[(int)token & 0xff]; |
| } |
| |
| /** |
| * Change the token to use a new type. |
| * |
| * @param token The original token. |
| * @param newType The new token type. |
| * @return The recast token. |
| */ |
| public static long recast(final long token, final TokenType newType) { |
| return token & ~0xFFL | newType.ordinal(); |
| } |
| |
| /** |
| * Return a string representation of a token. |
| * @param source Token source. |
| * @param token Token descriptor. |
| * @param verbose True to include details. |
| * @return String representation. |
| */ |
| public static String toString(final Source source, final long token, final boolean verbose) { |
| final TokenType type = Token.descType(token); |
| String result; |
| |
| if (source != null && type.getKind() == LITERAL) { |
| result = source.getString(token); |
| } else { |
| result = type.getNameOrType(); |
| } |
| |
| if (verbose) { |
| final int position = Token.descPosition(token); |
| final int length = Token.descLength(token); |
| result += " (" + position + ", " + length + ")"; |
| } |
| |
| return result; |
| } |
| |
| /** |
| * String conversion of token |
| * |
| * @param source the source |
| * @param token the token |
| * |
| * @return token as string |
| */ |
| public static String toString(final Source source, final long token) { |
| return Token.toString(source, token, false); |
| } |
| |
| /** |
| * String conversion of token - version without source given |
| * |
| * @param token the token |
| * |
| * @return token as string |
| */ |
| public static String toString(final long token) { |
| return Token.toString(null, token, false); |
| } |
| |
| /** |
| * Static hash code computation function token |
| * |
| * @param token a token |
| * |
| * @return hash code for token |
| */ |
| public static int hashCode(final long token) { |
| return (int)(token ^ token >>> 32); |
| } |
| |
| } |