X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=src%2Forg%2Fxwt%2Fjs%2FLexer.java;h=81066bb88cb96efe7a165f4271ddb9069591d4d8;hb=bbf5ef35ca37016d19d92deffc0c992428c3bf6d;hp=f7039f47a07d7c6a596e90b4195baa64650e3e4b;hpb=50e2af974eb7f486af60f2ea831a305972db2749;p=org.ibex.core.git diff --git a/src/org/xwt/js/Lexer.java b/src/org/xwt/js/Lexer.java index f7039f4..81066bb 100644 --- a/src/org/xwt/js/Lexer.java +++ b/src/org/xwt/js/Lexer.java @@ -25,13 +25,16 @@ class Lexer implements Tokens { /** for debugging */ public static void main(String[] s) throws Exception { - Lexer l = new Lexer(new InputStreamReader(System.in)); - int tok = 0; - while((tok = l.getToken()) != -1) System.out.println(codeToString[tok]); + Lexer l = new Lexer(new InputStreamReader(System.in), "stdin", 0); + int tok = 0; + while((tok = l.getToken()) != -1) System.out.println(codeToString[tok]); } /** the token that was just parsed */ protected int op; + + /** the most recently parsed token, regardless of pushbacks */ + protected int mostRecentlyReadToken; /** if the token just parsed was a NUMBER, this is the numeric value */ protected Number number = null; @@ -39,17 +42,25 @@ class Lexer implements Tokens { /** if the token just parsed was a NAME or STRING, this is the string value */ protected String string = null; - /** the line number of the current token */ - protected int line = 0; + /** the line number of the most recently lexed token */ + private int line = 0; + + /** the line number of the most recently parsed token */ + protected int parserLine = 0; /** the column number of the current token */ protected int col = 0; /** the name of the source code file being lexed */ - protected String sourceName = "unknown"; + protected String sourceName; private SmartReader in; - public Lexer(Reader r) throws IOException { in = new SmartReader(r); } + public Lexer(Reader r, String sourceName, int line) throws IOException { + this.sourceName = sourceName; + this.line = line; + this.parserLine = line; + in = new SmartReader(r); + } // Predicates /////////////////////////////////////////////////////////////////////// @@ -67,8 +78,8 @@ class Lexer implements Tokens { // Token Subtype Handlers ///////////////////////////////////////////////////////// private int getKeyword(String s) throws IOException { - char c; - switch (s.length()) { + char c; + switch (s.length()) { case 2: c=s.charAt(1); if (c=='f') { if (s.charAt(0)=='i') return IF; } else if (c=='n') { if (s.charAt(0)=='i') return IN; } @@ -87,45 +98,45 @@ class Lexer implements Tokens { case 'c': c=s.charAt(3); if (c=='e') { if (s.charAt(2)=='s' && s.charAt(1)=='a') return CASE; } else if (c=='r') { if (s.charAt(2)=='a' && s.charAt(1)=='h') return RESERVED; } - return -1; + return -1; case 'e': c=s.charAt(3); if (c=='e') { if (s.charAt(2)=='s' && s.charAt(1)=='l') return ELSE; } else if (c=='m') { if (s.charAt(2)=='u' && s.charAt(1)=='n') return RESERVED; } - return -1; + return -1; case 'g': return s.equals("goto") ? RESERVED : -1; - case 'l': return s.equals("long") ? RESERVED : -1; + case 'l': return s.equals("long") ? RESERVED : -1; case 'n': return s.equals("null") ? NULL : -1; case 't': c=s.charAt(3); if (c=='e') { if (s.charAt(2)=='u' && s.charAt(1)=='r') return TRUE; } else if (c=='s') { if (s.charAt(2)=='i' && s.charAt(1)=='h') return THIS; } - return -1; - case 'w': if (s.equals("with")) return RESERVED; else return -1; - case 'v': if (s.equals("void")) return RESERVED; else return -1; + return -1; + case 'w': if (s.equals("with")) return RESERVED; else return -1; + case 'v': if (s.equals("void")) return RESERVED; else return -1; } break; case 5: switch (s.charAt(2)) { case 'a': return s.equals("class") ? RESERVED : -1; - case 'e': return s.equals("break") ? BREAK : -1; + case 'e': return s.equals("break") ? BREAK : -1; case 'i': return s.equals("while") ? WHILE : -1; - case 'l': return s.equals("false") ? FALSE : -1; + case 'l': return s.equals("false") ? FALSE : -1; case 'n': c=s.charAt(0); - if (s.equals("const")) return RESERVED; + if (s.equals("const")) return RESERVED; else if (s.equals("final")) return RESERVED; - return -1; - case 'o': c=s.charAt(0); - if (c == 'c') return s.equals("float") ? RESERVED : -1; - else if (c=='s') return s.equals("final") ? RESERVED : -1; - break; - case 'p': return s.equals("super") ? RESERVED : -1; + return -1; + case 'o': c=s.charAt(0); + if (c == 'c') return s.equals("float") ? RESERVED : -1; + else if (c=='s') return s.equals("final") ? RESERVED : -1; + break; + case 'p': return s.equals("super") ? RESERVED : -1; case 'r': return s.equals("throw") ? THROW : -1; case 't': return s.equals("catch") ? CATCH : -1; } break; case 6: switch (s.charAt(1)) { - case 'a': return s.equals("class") ? RESERVED : -1; + case 'a': return s.equals("class") ? RESERVED : -1; case 'e': c=s.charAt(0); if (s.equals("delete")) return RESERVED; else if (c=='r') return s.equals("return") ? RETURN : -1; break; - case 'h': return s.equals("throws") ? RESERVED : -1; + case 'h': return s.equals("throws") ? RESERVED : -1; case 'o': return s.equals("double") ? RESERVED : -1; case 's': return s.equals("assert") ? ASSERT : -1; case 'u': return s.equals("public") ? RESERVED : -1; @@ -158,7 +169,7 @@ class Lexer implements Tokens { break; case 12: return s.equals("synchronized") ? RESERVED : -1; } - return -1; + return -1; } private int getIdentifier(int c) throws IOException { @@ -167,7 +178,7 @@ class Lexer implements Tokens { in.unread(); String str = in.getString(); int result = getKeyword(str); - if (result == RESERVED) throw new LexerException("The reserved word \"" + str + "\" is not permitted in XWT scripts"); + if (result == RESERVED) throw new LexerException("The reserved word \"" + str + "\" is not permitted in XWT scripts"); if (result != -1) return result; this.string = str.intern(); return NAME; @@ -207,7 +218,7 @@ class Lexer implements Tokens { if (isInteger) { longval = Long.parseLong(numString, base); dval = (double)longval; - } else { + } else { dval = Double.parseDouble(numString); longval = (long) dval; if (longval == dval) isInteger = true; @@ -244,20 +255,20 @@ class Lexer implements Tokens { case 't': c = '\t'; break; case 'v': c = '\u000B'; break; case '\\': c = '\\'; break; - case 'u': { - int v = 0; - for(int i=0; i<4; i++) { - int ci = in.read(); - if (!((ci >= '0' && ci <= '9') || (ci >= 'a' && ci <= 'f') || (ci >= 'A' && ci <= 'F'))) - throw new LexerException("illegal character '" + ((char)c) + "' in \\u unicode escape sequence"); - v = (v << 8) | Integer.parseInt(ci + "", 16); - } - c = (char)v; - break; - } + case 'u': { + int v = 0; + for(int i=0; i<4; i++) { + int ci = in.read(); + if (!((ci >= '0' && ci <= '9') || (ci >= 'a' && ci <= 'f') || (ci >= 'A' && ci <= 'F'))) + throw new LexerException("illegal character '" + ((char)c) + "' in \\u unicode escape sequence"); + v = (v << 8) | Integer.parseInt(ci + "", 16); + } + c = (char)v; + break; + } default: - // just use the character that was escaped - break; + // just use the character that was escaped + break; } } if (stringBuf != null) stringBuf.append((char) c); @@ -272,7 +283,7 @@ class Lexer implements Tokens { return STRING; } - public int _getToken() throws IOException { + private int _getToken() throws IOException { int c; do { c = in.read(); } while (c == '\u0020' || c == '\u0009' || c == '\u000C' || c == '\u000B' || c == '\n' ); if (c == -1) return -1; @@ -303,7 +314,7 @@ class Lexer implements Tokens { case '*': return in.match('=') ? ASSIGN_MUL : MUL; case '<': return !in.match('<') ? (in.match('=') ? LE : LT) : in.match('=') ? ASSIGN_LSH : LSH; case '>': return !in.match('>') ? (in.match('=') ? GE : GT) : - in.match('>') ? (in.match('=') ? ASSIGN_URSH : URSH) : (in.match('=') ? ASSIGN_RSH : RSH); + in.match('>') ? (in.match('=') ? ASSIGN_URSH : URSH) : (in.match('=') ? ASSIGN_RSH : RSH); case '/': if (in.match('=')) return ASSIGN_DIV; if (in.match('/')) { while ((c = in.read()) != -1 && c != '\n'); in.unread(); return getToken(); } @@ -330,9 +341,11 @@ class Lexer implements Tokens { public SmartReader(Reader r) { reader = new PushbackReader(r); } public void unread() throws IOException { unread((char)lastread); } public void unread(char c) throws IOException { - reader.unread(c); - if (accumulator != null) accumulator.setLength(accumulator.length() - 1); - } + reader.unread(c); + if(c == '\n') col = -1; + else col--; + if (accumulator != null) accumulator.setLength(accumulator.length() - 1); + } public boolean match(char c) throws IOException { if (peek() == c) { reader.read(); return true; } else return false; } public int peek() throws IOException { int peeked = reader.read(); @@ -342,17 +355,21 @@ class Lexer implements Tokens { public int read() throws IOException { lastread = reader.read(); if (accumulator != null) accumulator.append((char)lastread); - if (lastread != '\n' && lastread != '\r') col++; - if (lastread == '\n') { line++; col = 0; } + if (lastread != '\n' && lastread != '\r') col++; + if (lastread == '\n') { + // col is -1 if we just unread a newline, this is sort of ugly + if (col != -1) parserLine = ++line; + col = 0; + } return lastread; } // FEATURE: could be much more efficient StringBuffer accumulator = null; public void startString() { - accumulator = new StringBuffer(); - accumulator.append((char)lastread); - } + accumulator = new StringBuffer(); + accumulator.append((char)lastread); + } public String getString() throws IOException { String ret = accumulator.toString(); accumulator = null; @@ -368,45 +385,48 @@ class Lexer implements Tokens { private Object[] pushBackObjects = new Object[10]; /** push back a token */ - public void pushBackToken(int op, Object obj) { - if (pushBackDepth >= pushBackInts.length - 1) { - int[] newInts = new int[pushBackInts.length * 2]; - System.arraycopy(pushBackInts, 0, newInts, 0, pushBackInts.length); - pushBackInts = newInts; - Object[] newObjects = new Object[pushBackObjects.length * 2]; - System.arraycopy(pushBackObjects, 0, newObjects, 0, pushBackObjects.length); - pushBackObjects = newObjects; - } - pushBackInts[pushBackDepth] = op; - pushBackObjects[pushBackDepth] = obj; - pushBackDepth++; + public final void pushBackToken(int op, Object obj) { + if (pushBackDepth >= pushBackInts.length - 1) { + int[] newInts = new int[pushBackInts.length * 2]; + System.arraycopy(pushBackInts, 0, newInts, 0, pushBackInts.length); + pushBackInts = newInts; + Object[] newObjects = new Object[pushBackObjects.length * 2]; + System.arraycopy(pushBackObjects, 0, newObjects, 0, pushBackObjects.length); + pushBackObjects = newObjects; + } + pushBackInts[pushBackDepth] = op; + pushBackObjects[pushBackDepth] = obj; + pushBackDepth++; } /** push back the most recently read token */ - public void pushBackToken() { pushBackToken(op, number != null ? (Object)number : (Object)string); } + public final void pushBackToken() { pushBackToken(op, number != null ? (Object)number : (Object)string); } /** read a token but leave it in the stream */ - public int peekToken() throws IOException { - int ret = getToken(); - pushBackToken(); - return ret; + public final int peekToken() throws IOException { + int ret = getToken(); + pushBackToken(); + return ret; } /** read a token */ - public int getToken() throws IOException { - number = null; - string = null; - if (pushBackDepth == 0) return op = _getToken(); - pushBackDepth--; - op = pushBackInts[pushBackDepth]; - if (pushBackObjects[pushBackDepth] != null) { - number = pushBackObjects[pushBackDepth] instanceof Number ? (Number)pushBackObjects[pushBackDepth] : null; - string = pushBackObjects[pushBackDepth] instanceof String ? (String)pushBackObjects[pushBackDepth] : null; - } - return op; + public final int getToken() throws IOException { + number = null; + string = null; + if (pushBackDepth == 0) { + mostRecentlyReadToken = op; + return op = _getToken(); + } + pushBackDepth--; + op = pushBackInts[pushBackDepth]; + if (pushBackObjects[pushBackDepth] != null) { + number = pushBackObjects[pushBackDepth] instanceof Number ? (Number)pushBackObjects[pushBackDepth] : null; + string = pushBackObjects[pushBackDepth] instanceof String ? (String)pushBackObjects[pushBackDepth] : null; + } + return op; } class LexerException extends IOException { - public LexerException(String s) { super(sourceName + ":" + line + "," + col + ": " + s); } + public LexerException(String s) { super(sourceName + ":" + line + "," + col + ": " + s); } } }