1 /*
2 * Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 import java.io.*;
25 import java.util.*;
26
27 /*
28 assignment : key = value;
29 key : string
30 value : string | array | dict
31 nValue : , value
32 array : ( value nValue )
33 nAssignment: , assignment|value
34 dict : { assignment* }
35 string : "*" or anything but a ,(){}=
36
37 special characters: ,(){}=
38 */
39
40 public class PParser {
41 protected static final int OPEN_PAIR = 1;
42 protected static final int CLOSE_PAIR = 2;
43 protected static final int OPEN_ARRAY = 3;
44 protected static final int CLOSE_ARRAY = 4;
45 protected static final int MORE = 5;
46 protected static final int EQUAL = 6;
47 protected static final int STRING = 7;
48 protected static final int WS = 8;
49
50 protected Reader reader;
51 protected boolean bufferedToken;
52 protected StringBuffer stringBuffer = new StringBuffer();
53 protected int lastChar;
54 protected int lastToken;
55 protected int lineNumber;
56 protected int column;
57
58 public PParser() {
59 }
60
61 public Hashtable parse(Reader r) throws IOException {
62 this.reader = r;
63 bufferedToken = false;
64 lineNumber = 0;
65 column = 0;
66 if (getToken() != OPEN_PAIR) {
67 error("No initial open");
68 }
69 return parsePair();
70 }
71
72 protected Object parseValue(int lookAhead) throws IOException {
73 int token;
74
75 if (lookAhead == -1) {
76 token = getToken();
77 }
78 else {
79 token = lookAhead;
80 }
81 switch (token) {
82 case STRING:
83 return stringBuffer.toString();
84 case OPEN_ARRAY:
85 return parseArray();
86 case OPEN_PAIR:
87 return parsePair();
88 default:
89 error("Expecting value");
90 }
91 return null;
92 }
93
94 protected Object parseArray() throws IOException {
95 Vector array = new Vector();
96 int token;
97
98 while ((token = getToken()) != CLOSE_ARRAY) {
99 if (token == MORE) {
100 token = getToken();
101 }
102 if (token != CLOSE_ARRAY) {
103 array.addElement(parseValue(token));
104 }
105 }
106 return array;
107 }
108
109 protected Hashtable parsePair() throws IOException {
110 Hashtable ht = new Hashtable(11);
111 int token;
112
113 while ((token = getToken()) != CLOSE_PAIR) {
114 if (token != STRING) {
115 error("Pair expecting string got");
116 }
117 String key = stringBuffer.toString();
118
119 if (getToken() != EQUAL) {
120 error("Expecting = ");
121 }
122
123 Object value = parseValue(-1);
124
125 ht.put(key, value);
126 }
127 return ht;
128 }
129
130 protected void ungetToken() {
131 if (bufferedToken) {
132 error("Can not buffer more than one token");
133 }
134 bufferedToken = true;
135 }
136
137 protected int getToken() throws IOException {
138 int token = getToken(false, false);
139
140 return token;
141 }
142
143 protected int getToken(boolean wantsWS, boolean inString)
144 throws IOException {
145 if (bufferedToken) {
146 bufferedToken = false;
147 if (lastToken != WS || wantsWS) {
148 return lastToken;
149 }
150 }
151 while ((lastChar = reader.read()) != -1) {
152 // If a line starts with '#', skip the line.
153 if (column == 0 && lastChar == '#') {
154 while ((lastChar = reader.read()) != -1
155 && lastChar != '\n') {
156 }
157 if (lastChar == -1) {
158 break;
159 }
160 }
161
162 column++;
163 switch(lastChar) {
164 case '\n':
165 lineNumber++;
166 column = 0;
167 case ' ':
168 case '\r':
169 case '\t':
170 if (wantsWS) {
171 lastToken = WS;
172 return WS;
173 }
174 break;
175 case ',':
176 lastToken = MORE;
177 return MORE;
178 case '(':
179 lastToken = OPEN_ARRAY;
180 return OPEN_ARRAY;
181 case ')':
182 lastToken = CLOSE_ARRAY;
183 return CLOSE_ARRAY;
184 case '{':
185 lastToken = OPEN_PAIR;
186 return OPEN_PAIR;
187 case '}':
188 lastToken = CLOSE_PAIR;
189 return CLOSE_PAIR;
190 case '=':
191 lastToken = EQUAL;
192 return EQUAL;
193 case '"':
194 lastToken = STRING;
195 if (!inString) {
196 stringBuffer.setLength(0);
197 while (true) {
198 getToken(true, true);
199 if (lastChar == '"') {
200 lastToken = STRING;
201 return STRING;
202 }
203 stringBuffer.append((char)lastChar);
204 }
205 }
206 return STRING;
207 default:
208 lastToken = STRING;
209 if (!inString) {
210 stringBuffer.setLength(0);
211 stringBuffer.append((char)lastChar);
212 while (getToken(true, true) == STRING) {
213 if (lastChar == '"') {
214 error("Unexpected quote");
215 }
216 stringBuffer.append((char)lastChar);
217 }
218 ungetToken();
219 }
220 return STRING;
221 }
222 }
223 return -1;
224 }
225
226 protected void error(String errorString) {
227 throw new RuntimeException(errorString + " at line " + lineNumber + " column " + column);
228 }
229
230 public static void dump(Object o) {
231 if (o instanceof String) {
232 System.out.print(o);
233 }
234 else if(o instanceof Vector) {
235 Enumeration e = ((Vector)o).elements();
236
237 dump(" (");
238 while (e.hasMoreElements()) {
239 dump(e.nextElement());
240 dump(" -- ");
241 }
242 dump(" )");
243 }
244 else {
245 Hashtable ht = (Hashtable)o;
246 Enumeration e = ht.keys();
247
248 dump(" {");
249 while (e.hasMoreElements()) {
250 Object key = e.nextElement();
251
252 dump(key);
253 dump(" = ");
254 dump(ht.get(key));
255 dump(";");
256 }
257 dump(" }");
258 }
259 }
260
261 public static void main(String[] args) {
262 if (args.length == 0) {
263 System.out.println("need filename");
264 }
265 else {
266 try {
267 FileReader fr = new FileReader(args[0]);
268 PParser parser = new PParser();
269 Hashtable ht = parser.parse(fr);
270
271 dump(ht);
272 System.out.println();
273 }
274 catch (IOException ioe) {
275 System.out.println("Couldn't parse: " + ioe);
276 }
277 }
278 }
279 }