X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=Robust%2Fsrc%2FLex%2FLexer.java;fp=Robust%2Fsrc%2FLex%2FLexer.java;h=0000000000000000000000000000000000000000;hb=refs%2Ftags%2Fbuildscript;hp=fee2448e8db45e13218c3e937271361e71b2b9f9;hpb=ac6191b514c0e54b468623bf868134e1ce809df5;p=IRC.git

diff --git a/Robust/src/Lex/Lexer.java b/Robust/src/Lex/Lexer.java
deleted file mode 100644
index fee2448e..00000000
--- a/Robust/src/Lex/Lexer.java
+++ /dev/null
@@ -1,561 +0,0 @@
-package Lex;
-
-import java.io.Reader;
-import java.io.LineNumberReader;
-import Parse.Sym;
-
-/* Java lexer.
- * Copyright (C) 2002 C. Scott Ananian <cananian@alumni.princeton.edu>
- * This program is released under the terms of the GPL; see the file
- * COPYING for more details.  There is NO WARRANTY on this code.
- */
-
-public class Lexer {
-  LineNumberReader reader;
-  boolean isJava12;
-  boolean isJava14;
-  boolean isJava15;
-  String line = null;
-  int line_pos = 1;
-  int line_num = 0;
-  LineList lineL = new LineList(-line_pos, null); // sentinel for line #0
-
-  public Lexer(Reader reader) {
-    this.reader = new LineNumberReader(new EscapedUnicodeReader(reader));
-    this.isJava12 = true;
-    this.isJava14 = true;
-  }
-
-  public java_cup.runtime.Symbol nextToken() throws java.io.IOException {
-    java_cup.runtime.Symbol sym =
-      lookahead==null ? _nextToken() : lookahead.get();
-    last = sym;
-    return sym;
-  }
-  private boolean shouldBePLT() throws java.io.IOException {
-    // look ahead to see if this LT should be changed to a PLT
-    if (last==null || last.sym!=Sym.IDENTIFIER)
-      return false;
-    if (lookahead==null) lookahead = new FIFO(new FIFO.Getter() {
-                                                java_cup.runtime.Symbol next() throws java.io.IOException
-                                                { return _nextToken(); }
-					      });
-    int i=0;
-    // skip past IDENTIFIER (DOT IDENTIFIER)*
-    if (lookahead.peek(i++).sym != Sym.IDENTIFIER)
-      return false;
-    while (lookahead.peek(i).sym == Sym.DOT) {
-      i++;
-      if (lookahead.peek(i++).sym != Sym.IDENTIFIER)
-	return false;
-    }
-    // skip past (LBRACK RBRACK)*
-    while (lookahead.peek(i).sym == Sym.LBRACK) {
-      i++;
-      if (lookahead.peek(i++).sym != Sym.RBRACK)
-	return false;
-    }
-    // now the next sym has to be one of LT GT COMMA EXTENDS IMPLEMENTS
-    switch(lookahead.peek(i).sym) {
-    default:
-      return false;
-
-    case Sym.LT:
-    case Sym.GT:
-    case Sym.COMMA:
-    case Sym.EXTENDS:
-      return true;
-    }
-  }
-  private java_cup.runtime.Symbol last = null;
-  private FIFO lookahead = null;
-  public java_cup.runtime.Symbol _nextToken() throws java.io.IOException {
-    /* tokens are:
-     *  Identifiers/Keywords/true/false/null (start with java letter)
-     *  numeric literal (start with number)
-     *  character literal (start with single quote)
-     *  string (start with double quote)
-     *  separator (parens, braces, brackets, semicolon, comma, period)
-     *  operator (equals, plus, minus, etc)
-     *  whitespace
-     *  comment (start with slash)
-     */
-    InputElement ie;
-    int startpos, endpos;
-    do {
-      startpos = lineL.head + line_pos;
-      ie = getInputElement();
-      if (ie instanceof DocumentationComment)
-	comment = ((Comment)ie).getComment();
-    } while (!(ie instanceof Token));
-    endpos = lineL.head + line_pos - 1;
-
-    // System.out.println(ie.toString()); // uncomment to debug lexer.
-    java_cup.runtime.Symbol sym = ((Token)ie).token();
-    // fix up left/right positions.
-    sym.left = startpos; sym.right = endpos;
-    // return token.
-    return sym;
-  }
-  public boolean debug_lex() throws java.io.IOException {
-    InputElement ie = getInputElement();
-    System.out.println(ie);
-    return !(ie instanceof EOF);
-  }
-
-  String comment;
-  public String lastComment() {
-    return comment;
-  }
-  public void clearComment() {
-    comment="";
-  }
-
-  InputElement getInputElement() throws java.io.IOException {
-    if (line_num == 0)
-      nextLine();
-    if (line==null)
-      return new EOF();
-    if (line.length()<=line_pos) {      // end of line.
-      nextLine();
-      if (line==null)
-	return new EOF();
-    }
-
-    switch (line.charAt(line_pos)) {
-
-      // White space:
-    case ' ':    // ASCII SP
-    case '\t':    // ASCII HT
-    case '\f':    // ASCII FF
-    case '\n':    // LineTerminator
-      return new WhiteSpace(consume());
-
-      // EOF character:
-    case '\020': // ASCII SUB
-      consume();
-      return new EOF();
-
-      // Comment prefix:
-    case '/':
-      return getComment();
-
-      // else, a Token
-    default:
-      return getToken();
-    }
-  }
-  // May get Token instead of Comment.
-  InputElement getComment() throws java.io.IOException {
-    String comment;
-    // line.charAt(line_pos+0) is '/'
-    switch (line.charAt(line_pos+1)) {
-    case '/': // EndOfLineComment
-      comment = line.substring(line_pos+2);
-      line_pos = line.length();
-      return new EndOfLineComment(comment);
-
-    case '*': // TraditionalComment or DocumentationComment
-      line_pos += 2;
-      if (line.charAt(line_pos)=='*') { // DocumentationComment
-	return snarfComment(new DocumentationComment());
-      } else { // TraditionalComment
-	return snarfComment(new TraditionalComment());
-      }
-
-    default: // it's a token, not a comment.
-      return getToken();
-    }
-  }
-
-  Comment snarfComment(Comment c) throws java.io.IOException {
-    StringBuffer text=new StringBuffer();
-    while(true) { // Grab CommentTail
-      while (line.charAt(line_pos)!='*') { // Add NotStar to comment.
-	int star_pos = line.indexOf('*', line_pos);
-	if (star_pos<0) {
-	  text.append(line.substring(line_pos));
-	  c.appendLine(text.toString()); text.setLength(0);
-	  line_pos = line.length();
-	  nextLine();
-	  if (line==null)
-	    throw new Error("Unterminated comment at end of file.");
-	} else {
-	  text.append(line.substring(line_pos, star_pos));
-	  line_pos=star_pos;
-	}
-      }
-      // At this point, line.charAt(line_pos)=='*'
-      // Grab CommentTailStar starting at line_pos+1.
-      if (line.charAt(line_pos+1)=='/') { // safe because line ends with '\n'
-	c.appendLine(text.toString()); line_pos+=2; return c;
-      }
-      text.append(line.charAt(line_pos++)); // add the '*'
-    }
-  }
-
-  Token getToken() {
-    // Tokens are: Identifiers, Keywords, Literals, Separators, Operators.
-    switch (line.charAt(line_pos)) {
-      // Separators: (period is a special case)
-    case '(':
-    case ')':
-    case '{':
-    case '}':
-    case '[':
-    case ']':
-    case ';':
-    case ',':
-      return new Separator(consume());
-
-      // Operators:
-    case '=':
-    case '>':
-    case '<':
-    case '!':
-    case '~':
-    case '?':
-    case ':':
-    case '&':
-    case '|':
-    case '+':
-    case '-':
-    case '*':
-    case '/':
-    case '^':
-    case '%':
-      return getOperator();
-
-    case '\'':
-      return getCharLiteral();
-
-    case '\"':
-      return getStringLiteral();
-
-      // a period is a special case:
-    case '.':
-      if (Character.digit(line.charAt(line_pos+1),10)!=-1)
-	return getNumericLiteral();
-      else if (isJava15 &&
-               line.charAt(line_pos+1)=='.' &&
-               line.charAt(line_pos+2)=='.') {
-	consume(); consume(); consume();
-	return new Separator('\u2026'); // unicode ellipsis character.
-      } else return new Separator(consume());
-
-    default:
-      break;
-    }
-    if (Character.isJavaIdentifierStart(line.charAt(line_pos)))
-      return getIdentifier();
-    if (Character.isDigit(line.charAt(line_pos)))
-      return getNumericLiteral();
-    throw new Error("Illegal character on line "+line_num);
-  }
-
-  static final String[] keywords = new String[] {
-    "abstract", "assert", "atomic", "boolean", "break", "byte", "case", "catch", "char",
-    "class", "const", "continue", "default", "do", "double", "else", "enum",
-    "extends", "external", "final", "finally",
-    "flag", //keyword for failure aware computation
-    "float", "for", "global", "goto", "if",
-    "implements", "import", "instanceof", "int", "interface", "isavailable",
-    "long",
-    "native", "new", "optional", "package", "private", "protected", "public",
-    "return", "short", "static", "strictfp", "super", "switch", "synchronized",
-    "tag", "task", "taskexit", //keywords for failure aware computation
-    "this", "throw", "throws", "transient", "try", "void",
-    "volatile", "while"
-  };
-  Token getIdentifier() {
-    // Get id string.
-    StringBuffer sb = new StringBuffer().append(consume());
-
-    if (!Character.isJavaIdentifierStart(sb.charAt(0)))
-      throw new Error("Invalid Java Identifier on line "+line_num);
-    while (Character.isJavaIdentifierPart(line.charAt(line_pos)))
-      sb.append(consume());
-    String s = sb.toString();
-    // Now check against boolean literals and null literal.
-    if (s.equals("null")) return new NullLiteral();
-    if (s.equals("true")) return new BooleanLiteral(true);
-    if (s.equals("false")) return new BooleanLiteral(false);
-    // Check against keywords.
-    //  pre-java 1.5 compatibility:
-    if (!isJava15 && s.equals("enum")) return new Identifier(s);
-    //  pre-java 1.4 compatibility:
-    if (!isJava14 && s.equals("assert")) return new Identifier(s);
-    //  pre-java 1.2 compatibility:
-    if (!isJava12 && s.equals("strictfp")) return new Identifier(s);
-    // use binary search.
-    for (int l=0, r=keywords.length; r > l; ) {
-      int x = (l+r)/2, cmp = s.compareTo(keywords[x]);
-      if (cmp < 0) r=x;else l=x+1;
-      if (cmp== 0) return new Keyword(s);
-    }
-    // not a keyword.
-    return new Identifier(s);
-  }
-  NumericLiteral getNumericLiteral() {
-    int i;
-    // leading decimal indicates float.
-    if (line.charAt(line_pos)=='.')
-      return getFloatingPointLiteral();
-    // 0x indicates Hex.
-    if (line.charAt(line_pos)=='0' &&
-        (line.charAt(line_pos+1)=='x' ||
-         line.charAt(line_pos+1)=='X')) {
-      line_pos+=2; return getIntegerLiteral(/*base*/ 16);
-    }
-    // otherwise scan to first non-numeric
-    for (i=line_pos; Character.digit(line.charAt(i),10)!=-1; )
-      i++;
-    switch(line.charAt(i)) { // discriminate based on first non-numeric
-    case '.':
-    case 'f':
-    case 'F':
-    case 'd':
-    case 'D':
-    case 'e':
-    case 'E':
-      return getFloatingPointLiteral();
-
-    case 'L':
-    case 'l':
-    default:
-      if (line.charAt(line_pos)=='0')
-	return getIntegerLiteral(/*base*/ 8);
-      return getIntegerLiteral(/*base*/ 10);
-    }
-  }
-  NumericLiteral getIntegerLiteral(int radix) {
-    long val=0;
-    while (Character.digit(line.charAt(line_pos),radix)!=-1)
-      val = (val*radix) + Character.digit(consume(),radix);
-    if (line.charAt(line_pos) == 'l' ||
-        line.charAt(line_pos) == 'L') {
-      consume();
-      return new LongLiteral(val);
-    }
-    // we compare MAX_VALUE against val/2 to allow constants like
-    // 0xFFFF0000 to get past the test. (unsigned long->signed int)
-    if ((val/2) > Integer.MAX_VALUE ||
-        val    < Integer.MIN_VALUE)
-      throw new Error("Constant does not fit in integer on line "+line_num);
-    return new IntegerLiteral((int)val);
-  }
-  NumericLiteral getFloatingPointLiteral() {
-    String rep = getDigits();
-    if (line.charAt(line_pos)=='.')
-      rep+=consume() + getDigits();
-    if (line.charAt(line_pos)=='e' ||
-        line.charAt(line_pos)=='E') {
-      rep+=consume();
-      if (line.charAt(line_pos)=='+' ||
-          line.charAt(line_pos)=='-')
-	rep+=consume();
-      rep+=getDigits();
-    }
-    try {
-      switch (line.charAt(line_pos)) {
-      case 'f':
-      case 'F':
-	consume();
-	return new FloatLiteral(Float.valueOf(rep).floatValue());
-
-      case 'd':
-      case 'D':
-	consume();
-
-	/* falls through */
-      default:
-	return new DoubleLiteral(Double.valueOf(rep).doubleValue());
-      }
-    } catch (NumberFormatException e) {
-      throw new Error("Illegal floating-point on line "+line_num+": "+e);
-    }
-  }
-  String getDigits() {
-    StringBuffer sb = new StringBuffer();
-    while (Character.digit(line.charAt(line_pos),10)!=-1)
-      sb.append(consume());
-    return sb.toString();
-  }
-
-  Operator getOperator() {
-    char first = consume();
-    char second= line.charAt(line_pos);
-
-    switch(first) {
-      // single-character operators.
-    case '~':
-    case '?':
-    case ':':
-      return new Operator(new String(new char[] {first}));
-
-      // doubled operators
-    case '+':
-    case '-':
-    case '&':
-    case '|':
-      if (first==second)
-	return new Operator(new String(new char[] {first, consume()}));
-
-    default:
-      break;
-    }
-    // Check for trailing '='
-    if (second=='=')
-      return new Operator(new String(new char[] {first, consume()}));
-
-    // Special-case '<<', '>>' and '>>>'
-    if ((first=='<' && second=='<') || // <<
-        (first=='>' && second=='>')) {  // >>
-      String op = new String(new char[] {first, consume()});
-      if (first=='>' && line.charAt(line_pos)=='>') // >>>
-	op += consume();
-      if (line.charAt(line_pos)=='=') // <<=, >>=, >>>=
-	op += consume();
-      return new Operator(op);
-    }
-
-    // Otherwise return single operator.
-    return new Operator(new String(new char[] {first}));
-  }
-
-  CharacterLiteral getCharLiteral() {
-    char firstquote = consume();
-    char val;
-    switch (line.charAt(line_pos)) {
-    case '\\':
-      val = getEscapeSequence();
-      break;
-
-    case '\'':
-      throw new Error("Invalid character literal on line "+line_num);
-
-    case '\n':
-      throw new Error("Invalid character literal on line "+line_num);
-
-    default:
-      val = consume();
-      break;
-    }
-    char secondquote = consume();
-    if (firstquote != '\'' || secondquote != '\'')
-      throw new Error("Invalid character literal on line "+line_num);
-    return new CharacterLiteral(val);
-  }
-  StringLiteral getStringLiteral() {
-    char openquote = consume();
-    StringBuffer val = new StringBuffer();
-    while (line.charAt(line_pos)!='\"') {
-      switch(line.charAt(line_pos)) {
-      case '\\':
-	val.append(getEscapeSequence());
-	break;
-
-      case '\n':
-	throw new Error("Invalid string literal on line " + line_num);
-
-      default:
-	val.append(consume());
-	break;
-      }
-    }
-    char closequote = consume();
-    if (openquote != '\"' || closequote != '\"')
-      throw new Error("Invalid string literal on line " + line_num);
-
-    return new StringLiteral(val.toString().intern());
-  }
-
-  char getEscapeSequence() {
-    if (consume() != '\\')
-      throw new Error("Invalid escape sequence on line " + line_num);
-    switch(line.charAt(line_pos)) {
-    case 'b':
-      consume(); return '\b';
-
-    case 't':
-      consume(); return '\t';
-
-    case 'n':
-      consume(); return '\n';
-
-    case 'f':
-      consume(); return '\f';
-
-    case 'r':
-      consume(); return '\r';
-
-    case '\"':
-      consume(); return '\"';
-
-    case '\'':
-      consume(); return '\'';
-
-    case '\\':
-      consume(); return '\\';
-
-    case '0':
-    case '1':
-    case '2':
-    case '3':
-      return (char) getOctal(3);
-
-    case '4':
-    case '5':
-    case '6':
-    case '7':
-      return (char) getOctal(2);
-
-    default:
-      throw new Error("Invalid escape sequence on line " + line_num);
-    }
-  }
-  int getOctal(int maxlength) {
-    int i, val=0;
-    for (i=0; i<maxlength; i++)
-      if (Character.digit(line.charAt(line_pos), 8)!=-1) {
-	val = (8*val) + Character.digit(consume(), 8);
-      } else break;
-    if ((i==0) || (val>0xFF)) // impossible.
-      throw new Error("Invalid octal escape sequence in line " + line_num);
-    return val;
-  }
-
-  char consume() {
-    return line.charAt(line_pos++);
-  }
-  void nextLine() throws java.io.IOException {
-    line=reader.readLine();
-    if (line!=null) line=line+'\n';
-    lineL = new LineList(lineL.head+line_pos, lineL); // for error reporting
-    line_pos=0;
-    line_num++;
-  }
-
-  // Deal with error messages.
-  public void errorMsg(String msg, java_cup.runtime.Symbol info) {
-    int n=line_num, c=info.left-lineL.head;
-    for (LineList p = lineL; p!=null; p=p.tail, n--)
-      if (p.head<=info.left) {
-	c=info.left-p.head; break;
-      }
-    System.err.println(msg+" at line "+n);
-    num_errors++;
-  }
-  private int num_errors = 0;
-  public int numErrors() {
-    return num_errors;
-  }
-
-  class LineList {
-    int head;
-    LineList tail;
-    LineList(int head, LineList tail) {
-      this.head = head; this.tail = tail;
-    }
-  }
-}