001: /*
002: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
003: *
004: * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
005: *
006: * The contents of this file are subject to the terms of either the GNU
007: * General Public License Version 2 only ("GPL") or the Common
008: * Development and Distribution License("CDDL") (collectively, the
009: * "License"). You may not use this file except in compliance with the
010: * License. You can obtain a copy of the License at
011: * http://www.netbeans.org/cddl-gplv2.html
012: * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the
013: * specific language governing permissions and limitations under the
014: * License. When distributing the software, include this License Header
015: * Notice in each file and include the License file at
016: * nbbuild/licenses/CDDL-GPL-2-CP. Sun designates this
017: * particular file as subject to the "Classpath" exception as provided
018: * by Sun in the GPL Version 2 section of the License file that
019: * accompanied this code. If applicable, add the following below the
020: * License Header, with the fields enclosed by brackets [] replaced by
021: * your own identifying information:
022: * "Portions Copyrighted [year] [name of copyright owner]"
023: *
024: * Contributor(s):
025: *
026: * The Original Software is NetBeans. The Initial Developer of the Original
027: * Software is Sun Microsystems, Inc. Portions Copyright 1997-2007 Sun
028: * Microsystems, Inc. All Rights Reserved.
029: *
030: * If you wish your version of this file to be governed by only the CDDL
031: * or only the GPL Version 2, indicate your decision by adding
032: * "[Contributor] elects to include this software in this distribution
033: * under the [CDDL or GPL Version 2] license." If you do not indicate a
034: * single choice of license, a recipient has the option to distribute
035: * your version of this file under either the CDDL, the GPL Version 2 or
036: * to extend the choice of license to its licensees as provided above.
037: * However, if you add GPL Version 2 code and therefore, elected the GPL
038: * Version 2 license, then the option applies only if the new code is
039: * made subject to such option by the copyright holder.
040: */
041:
042: package org.netbeans.lib.lexer;
043:
044: import org.netbeans.lib.editor.util.ArrayUtilities;
045:
046: /**
047: * Provides characters to the clients.
048: * <br/>
049: * It's implemented either by lexer input operation or preprocessor operation.
050: *
051: * @author Miloslav Metelka
052: * @version 1.00
053: */
054:
055: public interface CharProvider {
056:
057: /**
058: * Read next char from input.
059: */
060: int read();
061:
062: /**
063: * Read char that was already read.
064: */
065: char readExisting(int index);
066:
067: /**
068: * Present read index.
069: */
070: int readIndex();
071:
072: /**
073: * Get cumulative length in the parent character providers
074: * that corresponds to the length in this provider.
075: */
076: int deepRawLength(int length);
077:
078: /**
079: * Get cumulative length shift in the parent character providers
080: * that corresponds to the given index.
081: */
082: int deepRawLengthShift(int index);
083:
084: /**
085: * Backup given number of characters.
086: * <br/>
087: * The EOF cannot be backup-ed.
088: */
089: void backup(int count);
090:
091: /**
092: * Retrieve present token length assigned
093: * during tokenRecognized() method.
094: */
095: int tokenLength();
096:
097: /**
098: * Notify this provider that a token with the given length was recognized.
099: * <br/>
100: * The token length for this particular provider may differ from the real
101: * token length in the root lexer input operation due to character
102: * preprocessing.
103: * <br/>
104: * The tokenLength should be cached by this provider.
105: * @param skip whether the token will be skipped due to filtering of its id.
106: * @return true if the token is preprocessed or false otherwise.
107: */
108: void tokenRecognized(int tokenLength);
109:
110: /**
111: * Notify this provider that the token was approved and
112: * that the tokenLength number of characters should be skipped
113: * (tokenLength should be cached by the provider).
114: */
115: void tokenApproved();
116:
117: /**
118: * Collect extra preprocessed characters from the parent providers.
119: * <br/>
120: * They can consist from extra characters before the preprocessed characters
121: * in the top provider and the extra characters after
122: * the preprocessed characters in the top provider.
123: *
124: * @param epc non-null extra preprocessed characters.
125: * @param prepStartIndex first preprocessed index in the parent provider.
126: * @param prepEndIndex first non-preprocessed index in the parent provider.
127: * @param topPrepEndIndex top provider's prep end index - needed for proper
128: * computation of raw length shift.
129: */
130: void collectExtraPreprocessedChars(ExtraPreprocessedChars epc,
131: int prepStartIndex, int prepEndIndex, int topPrepEndIndex);
132:
133: /**
134: * Storage of the extra preprocessed characters in parent providers.
135: */
136: public static final class ExtraPreprocessedChars {
137:
138: private int preStartIndex;
139:
140: private int postEndIndex;
141:
142: private char[] extraPrepChars = ArrayUtilities.emptyCharArray();
143:
144: private int[] extraRawLengthShifts;
145:
146: public void ensureExtraLength(int length) {
147: int preLength = extraPrepChars.length - preStartIndex;
148: length += postEndIndex + preLength;
149: if (length > extraPrepChars.length) {
150: length <<= 1;
151: extraPrepChars = ArrayUtilities.charArray(
152: extraPrepChars, length, postEndIndex,
153: preStartIndex - postEndIndex);
154: extraRawLengthShifts = ArrayUtilities.intArray(
155: extraRawLengthShifts, length, postEndIndex,
156: preStartIndex - postEndIndex);
157: preStartIndex = extraPrepChars.length - preLength;
158: }
159: }
160:
161: public void insert(char ch, int rawLengthShift) {
162: preStartIndex--;
163: extraPrepChars[extraPrepChars.length - preStartIndex] = ch;
164: extraRawLengthShifts[extraPrepChars.length - preStartIndex] = rawLengthShift;
165: }
166:
167: public void append(char ch, int rawLengthShift) {
168: extraPrepChars[postEndIndex] = ch;
169: extraRawLengthShifts[postEndIndex] = rawLengthShift;
170: postEndIndex++;
171: }
172:
173: public void clear() {
174: preStartIndex = extraPrepChars.length;
175: postEndIndex = 0;
176: }
177:
178: public int preStartIndex() {
179: return preStartIndex;
180: }
181:
182: public int postEndIndex() {
183: return postEndIndex;
184: }
185:
186: public char[] extraPrepChars() {
187: return extraPrepChars;
188: }
189:
190: public int[] extraRawLengthShifts() {
191: return extraRawLengthShifts;
192: }
193:
194: }
195:
196: }
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