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1
5 package org.h2.bnf;
6
7 import java.io.ByteArrayInputStream  ;
8 import java.io.InputStreamReader ;
9 import java.io.Reader ;
10 import java.sql.ResultSet ;
11 import java.util.ArrayList ;
12 import java.util.HashMap ;
13 import java.util.Iterator ;
14 import java.util.Random ;
15 import java.util.StringTokenizer ;
16
17 import org.h2.server.web.DbContextRule;
18 import org.h2.tools.Csv;
19 import org.h2.util.Resources;
20 import org.h2.util.StringUtils;
21
22 public class Bnf {
23
24 static boolean COMBINE_KEYWORDS;
25
26 private static final String SEPARATORS = " [](){}|.,\r\n<>:-+*/=<\">!'";
27 private static final long MAX_PARSE_TIME = 100;
28
29 private Random random;
30 private HashMap ruleMap = new HashMap ();
31 private String syntax;
32 private String currentToken;
33 private String [] tokens;
34 private char firstChar;
35 private int index;
36 private Rule lastRepeat;
37 private ArrayList statements;
38 private String currentTopic;
39
40
46 public static Bnf getInstance(Reader csv) throws Exception {
47 Bnf bnf = new Bnf();
48 if(csv == null) {
49 byte[] data = Resources.get("/org/h2/res/help.csv");
50 csv = new InputStreamReader (new ByteArrayInputStream (data));
51 }
52 bnf.parse(csv);
53 return bnf;
54 }
55
56 Bnf() {
57 this.random = new Random ();
58 random.setSeed(1);
59 }
60
61 void addFixedRule(String name, int fixedType) {
62 Rule rule = new RuleFixed(fixedType);
63 addRule(name, 0, "Fixed", rule);
64 }
65
66 RuleHead addRule(String topic, int id, String section, Rule rule) {
67 RuleHead head = new RuleHead(id, section, topic, rule);
68 if(ruleMap.get(StringUtils.toLowerEnglish(topic)) != null) {
69 throw new Error ("already exists: " + topic);
70 }
71 ruleMap.put(StringUtils.toLowerEnglish(topic), head);
72 return head;
73 }
74
75 public Random getRandom() {
76 return random;
77 }
78
79 public HashMap getRuleMap() {
80 return ruleMap;
81 }
82
83 public void parse(Reader csv) throws Exception {
84 Rule functions = null;
85 statements = new ArrayList ();
86 ResultSet rs = Csv.getInstance().read(csv, null);
87 for(int id=0; rs.next(); id++) {
88 String section = rs.getString("SECTION").trim();
89 if(section.startsWith("System")) {
90 continue;
91 }
92 String topic = StringUtils.toLowerEnglish(rs.getString("TOPIC").trim());
93 topic = StringUtils.replaceAll(topic, " ", "");
94 topic = StringUtils.replaceAll(topic, "_", "");
95 syntax = rs.getString("SYNTAX").trim();
96 currentTopic = section;
97 if(section.startsWith("Function")) {
98 int end = syntax.indexOf(':');
99 syntax = syntax.substring(0, end);
100 }
101 tokens = tokenize();
102 index = 0;
103 Rule rule = parseRule();
104 if(section.startsWith("Command")) {
105 rule = new RuleList(rule, new RuleElement(";\n\n", currentTopic), false);
106 }
107 RuleHead head = addRule(topic, id, section, rule);
108 if(section.startsWith("Function")) {
109 if(functions == null) {
110 functions = rule;
111 } else {
112 functions = new RuleList(rule, functions, true);
113 }
114 } else if(section.startsWith("Commands")) {
115 statements.add(head);
116 }
117 }
118 addRule("@func@", 0, "Function", functions);
119 addFixedRule("@ymd@", RuleFixed.YMD);
120 addFixedRule("@hms@", RuleFixed.HMS);
121 addFixedRule("@nanos@", RuleFixed.NANOS);
122 addFixedRule("anythingExceptSingleQuote", RuleFixed.ANY_EXCEPT_SINGLE_QUOTE);
123 addFixedRule("anythingExceptDoubleQuote", RuleFixed.ANY_EXCEPT_DOUBLE_QUOTE);
124 addFixedRule("anythingUntilEndOfLine", RuleFixed.ANY_UNTIL_EOL);
125 addFixedRule("anythingUntilEndComment", RuleFixed.ANY_UNTIL_END);
126 addFixedRule("anything", RuleFixed.ANY_WORD);
127 addFixedRule("@hexStart@", RuleFixed.HEXSTART);
128 addFixedRule("@concat@", RuleFixed.CONCAT);
129 addFixedRule("@az_@", RuleFixed.AZ_);
130 addFixedRule("@af@", RuleFixed.AF);
131 addFixedRule("@digit@", RuleFixed.DIGIT);
132 }
133
134 public String getSyntax(String rule, String syntax) {
135 StringTokenizer tokenizer = new StringTokenizer (syntax, SEPARATORS, true);
136 StringBuffer buff = new StringBuffer ();
137 while(tokenizer.hasMoreTokens()) {
138 String s = tokenizer.nextToken();
139 if(s.length() == 1 || StringUtils.toUpperEnglish(s).equals(s)) {
140 buff.append(s);
141 continue;
142 }
143 String section = null;
144 int id = -1;
145 for(int i=0; i<s.length(); i++) {
146 String test = StringUtils.toLowerEnglish(s.substring(i));
147 RuleHead r = (RuleHead)ruleMap.get(test);
148 if(r != null) {
149 id = r.id;
150 section = r.section;
151 break;
152 }
153 }
154 if(id == -1) {
155 buff.append(s);
156 continue;
157 }
158 String page = "grammar.html";
159 if(section.startsWith("Data Types")) {
160 page = "datatypes.html";
161 } else if(section.startsWith("Functions")) {
162 page = "functions.html";
163 }
164 buff.append("<a HREF=\""+page+"#sql"+id+"\">");
165 buff.append(s);
166 buff.append("</a>");
167 }
168 return buff.toString();
169 }
170
171 private Rule parseRule() {
172 read();
173 Rule r= parseOr();
174 return r;
175 }
176
177 private Rule parseOr() {
178 Rule r = parseList();
179 if(firstChar == '|') {
180 read();
181 r = new RuleList(r, parseOr(), true);
182 }
183 lastRepeat = r;
184 return r;
185 }
186
187 private Rule parseList() {
188 Rule r = parseToken();
189 if(firstChar != '|' && firstChar != ']' && firstChar != '}' && firstChar != 0) {
190 r = new RuleList(r, parseList(), false);
191 }
192 lastRepeat = r;
193 return r;
194 }
195
196 private Rule parseToken() {
197 Rule r;
198 if((firstChar >= 'A' && firstChar <= 'Z') || (firstChar >= 'a' && firstChar <= 'z')) {
199 r = new RuleElement(currentToken, currentTopic);
201 } else if(firstChar == '[') {
202 read();
203 Rule r2 = parseOr();
204 boolean repeat = false;
205 if(r2.last() instanceof RuleRepeat) {
206 repeat = true;
207 }
208 r = new RuleOptional(r2, repeat);
209 if(firstChar != ']') {
210 throw new Error ("expected ], got " + currentToken + " syntax:" + syntax);
211 }
212 } else if(firstChar == '{') {
213 read();
214 r = parseOr();
215 if(firstChar != '}') {
216 throw new Error ("expected }, got " + currentToken+ " syntax:" + syntax);
217 }
218 } else if("@commadots@".equals(currentToken)) {
219 r = new RuleList(new RuleElement(",", currentTopic), lastRepeat, false);
220 r = new RuleRepeat(r);
221 } else if("@dots@".equals(currentToken)) {
222 r = new RuleRepeat(lastRepeat);
223 } else {
224 r = new RuleElement(currentToken, currentTopic);
225 }
226 lastRepeat = r;
227 read();
228 return r;
229 }
230
231 private void read() {
232 if(index < tokens.length) {
233 currentToken = tokens[index++];
234 firstChar = currentToken.charAt(0);
235 } else {
236 currentToken = "";
237 firstChar = 0;
238 }
239 }
240
241 private String [] tokenize() {
242 ArrayList list = new ArrayList ();
243 syntax = StringUtils.replaceAll(syntax, "yyyy-MM-dd", "@ymd@");
244 syntax = StringUtils.replaceAll(syntax, "hh:mm:ss", "@hms@");
245 syntax = StringUtils.replaceAll(syntax, "nnnnnnnnn", "@nanos@");
246 syntax = StringUtils.replaceAll(syntax, "function", "@func@");
247 syntax = StringUtils.replaceAll(syntax, "0x", "@hexStart@");
248 syntax = StringUtils.replaceAll(syntax, ",...", "@commadots@");
249 syntax = StringUtils.replaceAll(syntax, "...", "@dots@");
250 syntax = StringUtils.replaceAll(syntax, "||", "@concat@");
251 syntax = StringUtils.replaceAll(syntax, "a-z|_", "@az_@");
252 syntax = StringUtils.replaceAll(syntax, "A-Z|_", "@az_@");
253 syntax = StringUtils.replaceAll(syntax, "a-f", "@af@");
254 syntax = StringUtils.replaceAll(syntax, "A-F", "@af@");
255 syntax = StringUtils.replaceAll(syntax, "0-9", "@digit@");
256 StringTokenizer tokenizer = new StringTokenizer (syntax, SEPARATORS, true);
257 while(tokenizer.hasMoreTokens()) {
258 String s = tokenizer.nextToken();
259 if(s.length() == 1) {
260 if(" \r\n".indexOf(s.charAt(0))>=0) {
261 continue;
262 }
263 }
264 list.add(s);
265 }
266 return (String []) list.toArray(new String [0]);
267 }
268
269 public HashMap getNextTokenList(String query) {
270 HashMap next = new HashMap ();
271 Sentence sentence = new Sentence();
272 sentence.next = next;
273 sentence.text = query;
274 for(int i=0; i<statements.size(); i++) {
275 RuleHead head = (RuleHead) statements.get(i);
276 if(!head.section.startsWith("Commands")) {
277 continue;
278 }
279 sentence.max = System.currentTimeMillis() + MAX_PARSE_TIME;
280 head.getRule().addNextTokenList(query, sentence);
281 }
282 return next;
283 }
284
285 public void linkStatements() {
286 HashMap ruleMap = getRuleMap();
287 for(Iterator it = ruleMap.values().iterator(); it.hasNext(); ) {
288 RuleHead r = (RuleHead) it.next();
289 r.getRule().setLinks(ruleMap);
290 }
291 }
292
293 public void updateTopic(String topic, DbContextRule rule) {
294 topic = StringUtils.toLowerEnglish(topic);
295 RuleHead head = (RuleHead) ruleMap.get(topic);
296 if(head == null) {
297 head = new RuleHead(0, "db", topic, rule);
298 ruleMap.put(topic, head);
299 statements.add(head);
300 } else {
301 head.rule = rule;
302 }
303 }
304
305 public void updateTopic(String topic, String [] array) {
306 topic = StringUtils.toLowerEnglish(topic);
307 ArrayList list = new ArrayList ();
308 for(int i=0; i<array.length; i++) {
309 list.add(new RuleElement(array[i], true, topic));
310 }
311 RuleList rule = new RuleList(list, true);
312 RuleHead head = (RuleHead) ruleMap.get(topic);
313 if(head == null) {
314 head = new RuleHead(0, "db", topic, rule);
315 ruleMap.put(topic, head);
316 statements.add(head);
317 } else {
318 head.rule = rule;
319 }
320 }
321
322 public ArrayList getStatements() {
323 return statements;
324 }
325
326 }
327 |
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