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 Map<String,Object> 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 } else {
78 token = lookAhead;
79 }
80 switch (token) {
81 case STRING:
82 return stringBuffer.toString();
83 case OPEN_ARRAY:
84 return parseArray();
85 case OPEN_PAIR:
86 return parsePair();
87 default:
88 error("Expecting value");
89 }
90 return null;
91 }
92
93 protected Object parseArray() throws IOException {
94 List<Object> array = new ArrayList<>();
95 int token;
96
97 while ((token = getToken()) != CLOSE_ARRAY) {
98 if (token == MORE) {
99 token = getToken();
100 }
101 if (token != CLOSE_ARRAY) {
102 array.add(parseValue(token));
103 }
104 }
105 return array;
106 }
107
108 protected Map<String,Object> parsePair() throws IOException {
109 Map<String,Object> ht = new HashMap<>(11);
110 int token;
111
112 while ((token = getToken()) != CLOSE_PAIR) {
113 if (token != STRING) {
114 error("Pair expecting string got");
115 }
116 String key = stringBuffer.toString();
117
118 if (getToken() != EQUAL) {
119 error("Expecting = ");
120 }
121
122 Object value = parseValue(-1);
123 ht.put(key, value);
124 }
125 return ht;
126 }
127
128 protected void ungetToken() {
129 if (bufferedToken) {
130 error("Can not buffer more than one token");
131 }
132 bufferedToken = true;
133 }
134
135 protected int getToken() throws IOException {
136 int token = getToken(false, false);
137
138 return token;
139 }
140
141 @SuppressWarnings("fallthrough")
142 protected int getToken(boolean wantsWS, boolean inString)
143 throws IOException {
144 if (bufferedToken) {
145 bufferedToken = false;
146 if (lastToken != WS || wantsWS) {
147 return lastToken;
148 }
149 }
150 while ((lastChar = reader.read()) != -1) {
151 // If a line starts with '#', skip the line.
152 if (column == 0 && lastChar == '#') {
153 while ((lastChar = reader.read()) != -1
154 && lastChar != '\n') {
155 }
156 if (lastChar == -1) {
157 break;
158 }
159 }
160
161 column++;
162 switch(lastChar) {
163 case '\n':
164 lineNumber++;
165 column = 0;
166 case ' ':
167 case '\r':
168 case '\t':
169 if (wantsWS) {
170 lastToken = WS;
171 return WS;
172 }
173 break;
174 case ',':
175 lastToken = MORE;
176 return MORE;
177 case '(':
178 lastToken = OPEN_ARRAY;
179 return OPEN_ARRAY;
180 case ')':
181 lastToken = CLOSE_ARRAY;
182 return CLOSE_ARRAY;
183 case '{':
184 lastToken = OPEN_PAIR;
185 return OPEN_PAIR;
186 case '}':
187 lastToken = CLOSE_PAIR;
188 return CLOSE_PAIR;
189 case '=':
190 lastToken = EQUAL;
191 return EQUAL;
192 case '"':
193 lastToken = STRING;
194 if (!inString) {
195 stringBuffer.setLength(0);
196 while (true) {
197 getToken(true, true);
198 if (lastChar == '"') {
199 lastToken = STRING;
200 return STRING;
201 }
202 stringBuffer.append((char)lastChar);
203 }
204 }
205 return STRING;
206 default:
207 lastToken = STRING;
208 if (!inString) {
209 stringBuffer.setLength(0);
210 stringBuffer.append((char)lastChar);
211 while (getToken(true, true) == STRING) {
212 if (lastChar == '"') {
213 error("Unexpected quote");
214 }
215 stringBuffer.append((char)lastChar);
216 }
217 ungetToken();
218 }
219 return STRING;
220 }
221 }
222 return -1;
223 }
224
225 protected void error(String errorString) {
226 throw new RuntimeException(errorString + " at line " + lineNumber + " column " + column);
227 }
228
229 @SuppressWarnings("unchecked")
230 public static void dump(Object o) {
231 if (o instanceof String) {
232 System.out.print(o);
233 } else if(o instanceof List) {
234 dump(" (");
235 ((List)o).forEach((l) -> {
236 dump(l);
237 dump(" -- ");
238 });
239 dump(" )");
240 } else {
241 Map<String,Object> ht = (Map<String,Object>)o;
242 dump(" {");
243 ht.keySet().forEach(l -> {
244 dump(l);
245 dump(" = ");
246 dump(ht.get(l));
247 dump(";");
248 });
249 dump(" }");
250 }
251 }
252
253 public static void main(String[] args) {
254 if (args.length == 0) {
255 System.out.println("need filename");
256 } else {
257 try {
258 FileReader fr = new FileReader(args[0]);
259 PParser parser = new PParser();
260 Map<String,Object> ht = parser.parse(fr);
261
262 dump(ht);
263 System.out.println();
264 }
265 catch (IOException ioe) {
266 System.out.println("Couldn't parse: " + ioe);
267 }
268 }
269 }
270 }