# jay skeleton for Java, tables via resource
# character in column 1 determines outcome...
# # is a comment
# . is copied
# t is copied as //t unless -t is set
# other lines are interpreted to call jay procedures
version Java tables 1.0.2 (c) 2002-2004 ats@cs.rit.edu
.
prolog ## %{ ... %} prior to the first %%
. // %token constants
tokens public static final int
.
. /** number of final state.
. */
yyFinal protected static final int yyFinal =
.
. /** parser tables.
. Cannot be final because they are loaded from a resource.
. Order is mandated by jay.
. */
. protected static short[] yyLhs, yyLen, yyDefRed, yyDgoto,
. yySindex, yyRindex, yyGindex, yyTable, yyCheck;
.
yyLhs //yy
yyLen //yy
yyDefRed //yy
yyDgoto //yy
yySindex //yy
yyRindex //yy
yyGindex //yy
yyTable //yy
yyCheck //yy
.
. /** maps symbol value to printable name.
. @see #yyExpecting
. */
. protected static String[] yyNames;
yyNames //yy
.
t /** printable rules for debugging.
t */
t protected static String[] yyRule;
t
yyRule //yy
.
. /** loads parser table.
. Format: name length newline ten-numbers newline ...
. */
. protected static short[] loadShort (java.io.BufferedReader in) throws Exception {
. java.util.StringTokenizer st = new java.util.StringTokenizer(in.readLine());
. st.nextToken();
. short[] result = new short[Integer.parseInt(st.nextToken())];
. for (int n = 0; n < result.length; n += 10) {
. st = new java.util.StringTokenizer(in.readLine(), ", \t\r\n");
. for (int m = 0; st.hasMoreTokens(); ++ m)
. result[n+m] = new Short(st.nextToken()).shortValue();
. }
. return result;
. }
.
. // once-only code to initialize parser tables
. // non-static to name resource after parser class
. // any error is fatal
. { if (yyLhs == null)
. try {
. Class myClass = getClass();
. String resource = myClass.getName().replace('.', '/')+".tables";
. java.io.InputStream i;
. try { // full path in jar file
. i = myClass.getResourceAsStream("/"+resource);
. } catch (Exception e) { // relative path
. i = myClass.getResourceAsStream(resource);
. }
. java.io.BufferedReader in =
. new java.io.BufferedReader(new java.io.InputStreamReader(i));
.
. yyLhs = loadShort(in);
. yyLen = loadShort(in);
. yyDefRed = loadShort(in);
. yyDgoto = loadShort(in);
. yySindex = loadShort(in);
. yyRindex = loadShort(in);
. yyGindex = loadShort(in);
. yyTable = loadShort(in);
. yyCheck = loadShort(in);
.
. // load name table
. // Format: yyNames length lines newline index space name newline ...for lines
. { java.util.StringTokenizer st = new java.util.StringTokenizer(in.readLine());
. st.nextToken();
. yyNames = new String[Integer.parseInt(st.nextToken())];
. int max = Integer.parseInt(st.nextToken());
. for (int n = 0; n < max; ++ n) {
. st = new java.util.StringTokenizer(in.readLine());
. int m = Integer.parseInt(st.nextToken());
. yyNames[m] = st.nextToken("\n").substring(1);
. }
. }
.
t // load rules table for debugging
t // Format: yyRule length newline rule newline ...for length
t { java.util.StringTokenizer st = new java.util.StringTokenizer(in.readLine());
t st.nextToken();
t yyRule = new String[Integer.parseInt(st.nextToken())];
t for (int n = 0; n < yyRule.length; ++ n)
t yyRule[n] = in.readLine();
t }
.
. in.close();
. } catch (Exception e) {
. throw new Error("cannot load parser tables ["+e+"]");
. }
. }
.
#
# --- rest is identical to skeleton.java ---
#
t /** debugging support, requires the package jay.yydebug.
t Set to null to suppress debugging messages.
t */
t protected jay.yydebug.yyDebug yydebug;
t
t /** index-checked interface to {@link #yyNames}.
t @param token single character or %token value.
t @return token name or [illegal] or [unknown].
t */
t public static final String yyName (int token) {
t if (token < 0 || token > yyNames.length) return "[illegal]";
t String name;
t if ((name = yyNames[token]) != null) return name;
t return "[unknown]";
t }
t
. /** thrown for irrecoverable syntax errors and stack overflow.
. Nested for convenience, does not depend on parser class.
. */
. public static class yyException extends java.lang.Exception {
. public yyException (String message) {
. super(message);
. }
. }
.
. /** must be implemented by a scanner object to supply input to the parser.
. Nested for convenience, does not depend on parser class.
. */
. public interface yyInput {
.
. /** move on to next token.
. @return false if positioned beyond tokens.
. @throws IOException on input error.
. */
. boolean advance () throws java.io.IOException;
.
. /** classifies current token.
. Should not be called if {@link #advance()} returned false.
. @return current %token or single character.
. */
. int token ();
.
. /** associated with current token.
. Should not be called if {@link #advance()} returned false.
. @return value for {@link #token()}.
. */
. Object value ();
. }
.
. /** simplified error message.
. @see #yyerror(java.lang.String, java.lang.String[])
. */
. public void yyerror (String message) {
. yyerror(message, null);
. }
.
. /** (syntax) error message.
. Can be overwritten to control message format.
. @param message text to be displayed.
. @param expected list of acceptable tokens, if available.
. */
. public void yyerror (String message, String[] expected) {
. if (expected != null && expected.length > 0) {
. System.err.print(message+", expecting");
. for (int n = 0; n < expected.length; ++ n)
. System.err.print(" "+expected[n]);
. System.err.println();
. } else
. System.err.println(message);
. }
.
. /** computes list of expected tokens on error by tracing the tables.
. @param state for which to compute the list.
. @return list of token names.
. */
. protected String[] yyExpecting (int state) {
. int token, n, len = 0;
. boolean[] ok = new boolean[yyNames.length];
.
. if ((n = yySindex[state]) != 0)
. for (token = n < 0 ? -n : 0;
. token < yyNames.length && n+token < yyTable.length; ++ token)
. if (yyCheck[n+token] == token && !ok[token] && yyNames[token] != null) {
. ++ len;
. ok[token] = true;
. }
. if ((n = yyRindex[state]) != 0)
. for (token = n < 0 ? -n : 0;
. token < yyNames.length && n+token < yyTable.length; ++ token)
. if (yyCheck[n+token] == token && !ok[token] && yyNames[token] != null) {
. ++ len;
. ok[token] = true;
. }
.
. String result[] = new String[len];
. for (n = token = 0; n < len; ++ token)
. if (ok[token]) result[n++] = yyNames[token];
. return result;
. }
.
. /** the generated parser, with debugging messages.
. Maintains a dynamic state and value stack.
. @param yyLex scanner.
. @param yydebug debug message writer implementing yyDebug, or null.
. @return result of the last reduction, if any.
. @throws yyException on irrecoverable parse error.
. */
. public Object yyparse (yyInput yyLex, Object yydebug)
. throws java.io.IOException, yyException {
t this.yydebug = (jay.yydebug.yyDebug)yydebug;
. return yyparse(yyLex);
. }
.
. /** initial size and increment of the state/value stack [default 256].
. This is not final so that it can be overwritten outside of invocations
. of {@link #yyparse}.
. */
. protected int yyMax;
.
. /** executed at the beginning of a reduce action.
. Used as $$ = yyDefault($1), prior to the user-specified action, if any.
. Can be overwritten to provide deep copy, etc.
. @param first value for $1, or null.
. @return first.
. */
. protected Object yyDefault (Object first) {
. return first;
. }
.
. /** the generated parser.
. Maintains a dynamic state and value stack.
. @param yyLex scanner.
. @return result of the last reduction, if any.
. @throws yyException on irrecoverable parse error.
. */
. public Object yyparse (yyInput yyLex) throws java.io.IOException, yyException {
. if (yyMax <= 0) yyMax = 256; // initial size
. int yyState = 0, yyStates[] = new int[yyMax]; // state stack
. Object yyVal = null, yyVals[] = new Object[yyMax]; // value stack
. int yyToken = -1; // current input
. int yyErrorFlag = 0; // #tokens to shift
.
local ## %{ ... %} after the first %%
. yyLoop: for (int yyTop = 0;; ++ yyTop) {
. if (yyTop >= yyStates.length) { // dynamically increase
. int[] i = new int[yyStates.length+yyMax];
. System.arraycopy(yyStates, 0, i, 0, yyStates.length);
. yyStates = i;
. Object[] o = new Object[yyVals.length+yyMax];
. System.arraycopy(yyVals, 0, o, 0, yyVals.length);
. yyVals = o;
. }
. yyStates[yyTop] = yyState;
. yyVals[yyTop] = yyVal;
t if (yydebug != null) yydebug.push(yyState, yyVal);
.
. yyDiscarded: for (;;) { // discarding a token does not change stack
. int yyN;
. if ((yyN = yyDefRed[yyState]) == 0) { // else [default] reduce (yyN)
. if (yyToken < 0) {
. yyToken = yyLex.advance() ? yyLex.token() : 0;
t if (yydebug != null)
t yydebug.lex(yyState, yyToken, yyName(yyToken), yyLex.value());
. }
. if ((yyN = yySindex[yyState]) != 0 && (yyN += yyToken) >= 0
. && yyN < yyTable.length && yyCheck[yyN] == yyToken) {
t if (yydebug != null)
t yydebug.shift(yyState, yyTable[yyN], yyErrorFlag > 0 ? yyErrorFlag-1 : 0);
. yyState = yyTable[yyN]; // shift to yyN
. yyVal = yyLex.value();
. yyToken = -1;
. if (yyErrorFlag > 0) -- yyErrorFlag;
. continue yyLoop;
. }
. if ((yyN = yyRindex[yyState]) != 0 && (yyN += yyToken) >= 0
. && yyN < yyTable.length && yyCheck[yyN] == yyToken)
. yyN = yyTable[yyN]; // reduce (yyN)
. else
. switch (yyErrorFlag) {
.
. case 0:
. yyerror("syntax error", yyExpecting(yyState));
t if (yydebug != null) yydebug.error("syntax error");
.
. case 1: case 2:
. yyErrorFlag = 3;
. do {
. if ((yyN = yySindex[yyStates[yyTop]]) != 0
. && (yyN += yyErrorCode) >= 0 && yyN < yyTable.length
. && yyCheck[yyN] == yyErrorCode) {
t if (yydebug != null)
t yydebug.shift(yyStates[yyTop], yyTable[yyN], 3);
. yyState = yyTable[yyN];
. yyVal = yyLex.value();
. continue yyLoop;
. }
t if (yydebug != null) yydebug.pop(yyStates[yyTop]);
. } while (-- yyTop >= 0);
t if (yydebug != null) yydebug.reject();
. throw new yyException("irrecoverable syntax error");
.
. case 3:
. if (yyToken == 0) {
t if (yydebug != null) yydebug.reject();
. throw new yyException("irrecoverable syntax error at end-of-file");
. }
t if (yydebug != null)
t yydebug.discard(yyState, yyToken, yyName(yyToken),
t yyLex.value());
. yyToken = -1;
. continue yyDiscarded; // leave stack alone
. }
. }
. int yyV = yyTop + 1-yyLen[yyN];
t if (yydebug != null)
t yydebug.reduce(yyState, yyStates[yyV-1], yyN, yyRule[yyN], yyLen[yyN]);
. yyVal = yyDefault(yyV > yyTop ? null : yyVals[yyV]);
. switch (yyN) {
actions ## code from the actions within the grammar
. }
. yyTop -= yyLen[yyN];
. yyState = yyStates[yyTop];
. int yyM = yyLhs[yyN];
. if (yyState == 0 && yyM == 0) {
t if (yydebug != null) yydebug.shift(0, yyFinal);
. yyState = yyFinal;
. if (yyToken < 0) {
. yyToken = yyLex.advance() ? yyLex.token() : 0;
t if (yydebug != null)
t yydebug.lex(yyState, yyToken,yyName(yyToken), yyLex.value());
. }
. if (yyToken == 0) {
t if (yydebug != null) yydebug.accept(yyVal);
. return yyVal;
. }
. continue yyLoop;
. }
. if ((yyN = yyGindex[yyM]) != 0 && (yyN += yyState) >= 0
. && yyN < yyTable.length && yyCheck[yyN] == yyState)
. yyState = yyTable[yyN];
. else
. yyState = yyDgoto[yyM];
t if (yydebug != null) yydebug.shift(yyStates[yyTop], yyState);
. continue yyLoop;
. }
. }
. }
.
epilog ## text following second %%