src/dolda/jsvc/next/Parser.java

   1 package dolda.jsvc.next;
   2
   3 import java.io.*;
   4 import java.util.*;
   5 import org.w3c.dom.*;
   6 import org.w3c.dom.bootstrap.*;
   7
   8 public class Parser {
   9     private static final DOMImplementation domimp;
  10
  11     static {
  12         DOMImplementationRegistry reg;
  13         try {
  14             reg = DOMImplementationRegistry.newInstance();
  15         } catch(Exception e) {
  16             throw(new Error(e));
  17         }
  18         DOMImplementation di = reg.getDOMImplementation("");
  19         if(di == null)
  20             throw(new RuntimeException("Could not get a DOM implemenation"));
  21         domimp = di;
  22     }
  23
  24     private static boolean namechar(char c) {
  25         return((c == ':') || (c == '_') || (c == '$') || (c == '.') || (c == '-') || ((c >= '0') && (c <= '9')) || ((c >= 'A') && (c <= 'Z')) || ((c >= 'a') && (c <= 'z')));
  26     }
  27
  28     protected String entity(String name) {
  29         if(name.equals("amp"))
  30             return("&");
  31         if(name.equals("lt"))
  32             return("<");
  33         if(name.equals("gt"))
  34             return(">");
  35         if(name.equals("apos"))
  36             return("'");
  37         if(name.equals("quot"))
  38             return("\"");
  39         return(null);
  40     }
  41
  42     protected Element makenode(Document doc, String name) {
  43         return(doc.createElementNS(null, name));
  44     }
  45
  46     protected Attr makeattr(Document doc, Element el, String name) {
  47         return(doc.createAttributeNS(el.getNamespaceURI(), name));
  48     }
  49
  50     public DocumentFragment parse(Reader in) throws IOException {
  51         Stack<Node> stack = new Stack<Node>();
  52         Document doc = domimp.createDocument(null, "dummy", null);
  53         DocumentFragment frag = doc.createDocumentFragment();
  54         stack.push(frag);
  55         String st = "content";
  56         int c = in.read();
  57         StringBuilder buf = new StringBuilder();
  58         StringBuilder ebuf = new StringBuilder();
  59         char atype = 0;
  60         int cdashcnt = 0;
  61         while(true) {
  62             if(st == "content") {
  63                 if(c == '<') {
  64                     st = "tag";
  65                     c = in.read();
  66                 } else if(c < 0) {
  67                     if(stack.peek() == frag)
  68                         return(frag);
  69                     else
  70                         throw(new ParseException("Unexpected end-of-file while parsing non-root element"));
  71                 } else {
  72                     st = "text";
  73                 }
  74             } else if(st == "tag") {
  75                 if(Character.isWhitespace((char)c)) {
  76                     c = in.read();
  77                 } else if(c == '!') {
  78                     cdashcnt = 0;
  79                     c = in.read();
  80                     st = "comment";
  81                 } else if(namechar((char)c)) {
  82                     st = "stag";
  83                 } else if(c == '/') {
  84                     c = in.read();
  85                     st = "etag";
  86                 } else if(c < 0) {
  87                     throw(new ParseException("Unexpected end-of-file while parsing tag"));
  88                 } else {
  89                     throw(new ParseException("Unexpected character `" + printable((char)c) + "' encountered in tag name"));
  90                 }
  91             } else if(st == "stag") {
  92                 boolean flush = false;
  93                 if(namechar((char)c)) {
  94                     buf.append((char)c);
  95                     c = in.read();
  96                 } else if(c == '>') {
  97                     flush = true;
  98                 } else if(Character.isWhitespace((char)c)) {
  99                     flush = true;
 100                     c = in.read();
 101                 } else if(c < 0) {
 102                     throw(new ParseException("Unexpected end-of-file while parsing tag name"));
 103                 } else {
 104                     throw(new ParseException("Unexpected character `" + printable((char)c) + "' encountered in tag name"));
 105                 }
 106                 if(flush) {
 107                     Element n = makenode(doc, buf.toString());
 108                     buf = new StringBuilder();
 109                     stack.peek().appendChild(n);
 110                     stack.push(n);
 111                     st = "attr";
 112                 }
 113             } else if(st == "comment") {
 114                 if(c == '-') {
 115                     cdashcnt++;
 116                     c = in.read();
 117                 } else if((c == '>') && (cdashcnt == 4)) {
 118                     stack.peek().appendChild(doc.createComment(buf.toString()));
 119                     buf = new StringBuilder();
 120                     st = "content";
 121                     c = in.read();
 122                 } else if(cdashcnt >= 2) {
 123                     if(cdashcnt > 2)
 124                         cdashcnt = 2;
 125                     buf.append((char)c);
 126                     c = in.read();
 127                 } else if(c < 0) {
 128                     throw(new ParseException("Unexpected end-of-file while parsing comment"));
 129                 } else {
 130                     throw(new ParseException("Unexpected character `" + printable((char)c) + "' encountered in comment"));
 131                 }
 132             } else if(st == "attr") {
 133                 if(namechar((char)c)) {
 134                     st = "aname";
 135                 } else if(c == '>') {
 136                     st = "content";
 137                     c = in.read();
 138                 } else if(c == '/') {
 139                     st = "stagend";
 140                     c = in.read();
 141                 } else if(Character.isWhitespace((char)c)) {
 142                     c = in.read();
 143                 } else if(c < 0) {
 144                     throw(new ParseException("Unexpected end-of-file while parsing attributes"));
 145                 } else {
 146                     throw(new ParseException("Unexpected character `" + printable((char)c) + "' encountered inside tag"));
 147                 }
 148             } else if(st == "stagend") {
 149                 if(c == '>') {
 150                     stack.pop();
 151                     c = in.read();
 152                     st = "content";
 153                 } else if(Character.isWhitespace((char)c)) {
 154                     c = in.read();
 155                 } else if(c < 0) {
 156                     throw(new ParseException("Unexpected end-of-file at end of empty tag"));
 157                 } else {
 158                     throw(new ParseException("Unexpected character `" + printable((char)c) + "' encountered at and of empty tag"));
 159                 }
 160             } else if(st == "aname") {
 161                 if(namechar((char)c)) {
 162                     buf.append((char)c);
 163                     c = in.read();
 164                 } else if(Character.isWhitespace((char)c)) {
 165                     c = in.read();
 166                 } else if(c == '=') {
 167                     Element el = (Element)stack.peek();
 168                     Attr attr = makeattr(doc, el, buf.toString());
 169                     el.setAttributeNodeNS(attr);
 170                     buf = new StringBuilder();
 171                     stack.push(attr);
 172                     st = "avalstart";
 173                     c = in.read();
 174                 } else if(c < 0) {
 175                     throw(new ParseException("Unexpected end-of-file while parsing attribute name"));
 176                 } else {
 177                     throw(new ParseException("Unexpected character `" + printable((char)c) + "' encountered in attribute name"));
 178                 }
 179             } else if(st == "avalstart") {
 180                 if((c == '\'') || (c == '"')) {
 181                     atype = (char)c;
 182                     c = in.read();
 183                     st = "aval";
 184                 } else if(Character.isWhitespace((char)c)) {
 185                     c = in.read();
 186                 } else if(c < 0) {
 187                     throw(new ParseException("Unexpected end-of-file while parsing attribute value"));
 188                 } else {
 189                     throw(new ParseException("Unexpected character `" + printable((char)c) + "' encountered in attribute value"));
 190                 }
 191             } else if(st == "aval") {
 192                 if(c == atype) {
 193                     c = in.read();
 194                     Attr a = (Attr)stack.pop();
 195                     a.setValue(buf.toString());
 196                     buf = new StringBuilder();
 197                     st = "attr";
 198                 } else if(c == '&') {
 199                     c = in.read();
 200                     st = "aent";
 201                 } else if(c < 0) {
 202                     throw(new ParseException("Unexpected end-of-file while parsing attribute value"));
 203                 } else {
 204                     buf.append((char)c);
 205                     c = in.read();
 206                 }
 207             } else if(st == "etag") {
 208                 if(namechar((char)c)) {
 209                     buf.append((char)c);
 210                     c = in.read();
 211                 } else if(c == '>') {
 212                     String nm = buf.toString();
 213                     buf = new StringBuilder();
 214                     Node n = stack.pop();
 215                     if(n instanceof DocumentFragment)
 216                         throw(new ParseException("Unexpected end tag for `" + nm + "' while parsing root content"));
 217                     Element el = (Element)n;
 218                     if(!nm.equals(el.getTagName()))
 219                         throw(new ParseException("Unexpected end tag for `" + nm + "' while parsing `" + el.getTagName() + "'"));
 220                     c = in.read();
 221                     st = "content";
 222                 } else if(c < 0) {
 223                     throw(new ParseException("Unexpected end-of-file while parsing end tag"));
 224                 } else {
 225                     throw(new ParseException("Unexpected character `" + printable((char)c) + "' encountered in end tag"));
 226                 }
 227             } else if(st == "text") {
 228                 boolean flush = false;
 229                 if(c == '&') {
 230                     st = "ent";
 231                     c = in.read();
 232                 } else if(c == '<') {
 233                     flush = true;
 234                     st = "content";
 235                 } else if(c < 0) {
 236                     flush = true;
 237                     st = "content";
 238                 } else {
 239                     buf.append((char)c);
 240                     c = in.read();
 241                 }
 242                 if(flush) {
 243                     Text n = doc.createTextNode(buf.toString());
 244                     buf = new StringBuilder();
 245                     stack.peek().appendChild(n);
 246                 }
 247             } else if(st == "ent") {
 248                 if(c == ';') {
 249                     String ename = ebuf.toString();
 250                     ebuf = new StringBuilder();
 251                     String rep = entity(ename);
 252                     if(rep == null)
 253                         throw(new ParseException("Unknown entity `" + ename + "' encountered"));
 254                     buf.append(rep);
 255                     st = "text";
 256                     c = in.read();
 257                 } else if(c < 0) {
 258                     throw(new ParseException("Unexpected end-of-file while parsing entity name"));
 259                 } else if(namechar((char)c)) {
 260                     ebuf.append((char)c);
 261                     c = in.read();
 262                 } else {
 263                     throw(new ParseException("Unexpected character `" + printable((char)c) + "' encountered in entity name"));
 264                 }
 265             } else if(st == "aent") {
 266                 if(c == ';') {
 267                     String ename = ebuf.toString();
 268                     ebuf = new StringBuilder();
 269                     String rep = entity(ename);
 270                     if(rep == null)
 271                         throw(new ParseException("Unknown entity `" + ename + "' encountered"));
 272                     buf.append(rep);
 273                     st = "aval";
 274                     c = in.read();
 275                 } else if(c < 0) {
 276                     throw(new ParseException("Unexpected end-of-file while parsing entity name"));
 277                 } else if(namechar((char)c)) {
 278                     ebuf.append((char)c);
 279                     c = in.read();
 280                 } else {
 281                     throw(new ParseException("Unexpected character `" + printable((char)c) + "' encountered in entity name"));
 282                 }
 283             } else {
 284                 throw(new Error("BUG: Typoed state " + st));
 285             }
 286         }
 287     }
 288
 289     private static String printable(char c) {
 290         if(c < 32)
 291             return(String.format("\\%03o", (int)c));
 292         return(Character.toString(c));
 293     }
 294
 295     public static void main(String[] args) throws Exception {
 296         Parser p = new Parser();
 297         DocumentFragment f = p.parse(new FileReader(args[0]));
 298         javax.xml.transform.TransformerFactory fac = javax.xml.transform.TransformerFactory.newInstance();
 299         fac.setAttribute("indent-number", 2);
 300         javax.xml.transform.Transformer t = fac.newTransformer();
 301         t.setOutputProperty(javax.xml.transform.OutputKeys.INDENT, "yes");
 302         t.transform(new javax.xml.transform.dom.DOMSource(f), new javax.xml.transform.stream.StreamResult(System.out));
 303         System.out.println(t.getClass());
 304     }
 305 }