| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.netbeans.modules.javascript2.lexer; |
| |
| import java.util.Stack; |
| import org.antlr.v4.runtime.CharStream; |
| import org.antlr.v4.runtime.misc.Interval; |
| import org.netbeans.spi.lexer.LexerInput; |
| import org.netbeans.spi.lexer.LexerRestartInfo; |
| |
| /** |
| * |
| * @author Petr Pisl |
| */ |
| public class NbLexerCharStream implements CharStream { |
| |
| private static final String STREAM_NAME = "NbLexerCharStream"; //NOI18N |
| private final LexerInput li; |
| private final Stack<Integer> markers = new Stack<>(); |
| |
| public NbLexerCharStream(LexerRestartInfo lri) { |
| this.li = lri.input(); |
| } |
| |
| @Override |
| public void consume() { |
| read(); |
| } |
| |
| @Override |
| public int LA(int lookahead) { |
| if (lookahead == 0) { |
| return 0; //the behaviour is not defined |
| } |
| |
| int c = 0; |
| for (int i = 0; i < lookahead; i++) { |
| c = read(); |
| } |
| li.backup(lookahead); |
| return c; |
| } |
| |
| @Override |
| public int mark() { |
| markers.push(index()); |
| return markers.size() - 1; |
| } |
| |
| @Override |
| public int index() { |
| return li.readLengthEOF(); |
| } |
| |
| @Override |
| public void release(int marker) { |
| if(markers.size() < marker) { |
| return ; //report? |
| } |
| |
| //remove all markers from the given one, including the requested one |
| do { |
| markers.pop(); |
| } while (marker < markers.size()); |
| } |
| |
| @Override |
| public void seek(int i) { |
| if (i < index()) { |
| //go backward |
| li.backup(index() - i); |
| } else { |
| // go forward |
| while (index() < i) { |
| consume(); |
| } |
| } |
| } |
| |
| @Override |
| public int size() { |
| return -1; //uknown |
| } |
| |
| @Override |
| public String getSourceName() { |
| return STREAM_NAME; |
| } |
| |
| private int read() { |
| int result = li.read(); |
| if (result == LexerInput.EOF) { |
| result = CharStream.EOF; |
| } |
| |
| return result; |
| } |
| |
| @Override |
| public String getText(Interval intrvl) { |
| return li.readText(intrvl.a, intrvl.b).toString(); |
| } |
| } |