| /* |
| * Copyright (c) 2013, the Dart project authors. |
| * |
| * Licensed under the Eclipse Public License v1.0 (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.eclipse.org/legal/epl-v10.html |
| * |
| * 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.google.dart.engine.services.internal.util; |
| |
| import com.google.common.collect.Lists; |
| import com.google.dart.engine.scanner.CharSequenceReader; |
| import com.google.dart.engine.scanner.Keyword; |
| import com.google.dart.engine.scanner.KeywordToken; |
| import com.google.dart.engine.scanner.Scanner; |
| import com.google.dart.engine.scanner.Token; |
| import com.google.dart.engine.scanner.TokenType; |
| |
| import java.util.List; |
| |
| /** |
| * Utilities to work with {@link Token}s. |
| */ |
| public class TokenUtils { |
| |
| /** |
| * @return the first {@link KeywordToken} with given {@link Keyword}, may be <code>null</code> if |
| * not found. |
| */ |
| public static KeywordToken findKeywordToken(List<Token> tokens, Keyword keyword) { |
| for (Token token : tokens) { |
| if (token instanceof KeywordToken) { |
| KeywordToken keywordToken = (KeywordToken) token; |
| if (keywordToken.getKeyword() == keyword) { |
| return keywordToken; |
| } |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * @return the first {@link Token} with given {@link TokenType}, may be <code>null</code> if not |
| * found. |
| */ |
| public static Token findToken(List<Token> tokens, TokenType type) { |
| for (Token token : tokens) { |
| if (token.getType() == type) { |
| return token; |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * @return {@link Token}s of the given Dart source, not <code>null</code>, may be empty if no |
| * tokens or some exception happens. |
| */ |
| public static List<Token> getTokens(final String s) { |
| try { |
| List<Token> tokens = Lists.newArrayList(); |
| Scanner scanner = new Scanner(null, new CharSequenceReader(s), null); |
| Token token = scanner.tokenize(); |
| while (token.getType() != TokenType.EOF) { |
| tokens.add(token); |
| token = token.getNext(); |
| } |
| return tokens; |
| } catch (Throwable e) { |
| return Lists.newArrayList(); |
| } |
| } |
| |
| /** |
| * @return <code>true</code> if given {@link Token}s contain only single {@link Token} with given |
| * {@link TokenType}. |
| */ |
| public static boolean hasOnly(List<Token> tokens, TokenType type) { |
| return tokens.size() == 1 && tokens.get(0).getType() == type; |
| } |
| } |