📄 calcscanner.java
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package com.croftsoft.apps.compiler;
import java.io.*;
import java.text.*;
import java.util.*;
import java_cup.runtime.*;
/*********************************************************************
* Token scanner for Calc.
*
* <B>Reference:</B>
*
* <P>
*
* "JLex: A Lexical Analyzer Generator for Java"<BR>
* <A HREF="http://www.cs.princeton.edu/~appel/modern/java/JLex/">
* http://www.cs.princeton.edu/~appel/modern/java/JLex/</A>
*
* @author
* <A HREF="http://www.alumni.caltech.edu/~croft/">David W. Croft</A>
* @version
* 1999-03-15
*********************************************************************/
//////////////////////////////////////////////////////////////////////
// Portions of this code machine-generated by JLex.
//////////////////////////////////////////////////////////////////////
public class CalcScanner implements CalcSymbols {
private final int YY_BUFFER_SIZE = 512;
private final int YY_F = -1;
private final int YY_NO_STATE = -1;
private final int YY_NOT_ACCEPT = 0;
private final int YY_START = 1;
private final int YY_END = 2;
private final int YY_NO_ANCHOR = 4;
private final char YYEOF = '\uFFFF';
//////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////
private static final String [ ] TEST_DATA = {
"1",
"22",
"333",
";",
"*",
"write(a);",
"bill_123" };
//////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////
public static void main ( String [ ] args )
throws Exception
//////////////////////////////////////////////////////////////////////
{
for ( int i = 0; i < TEST_DATA.length; i++ )
{
test ( TEST_DATA [ i ] );
}
}
public static void test ( String testText )
throws Exception
//////////////////////////////////////////////////////////////////////
{
Reader reader = new StringReader ( testText );
CalcScanner calcScanner = new CalcScanner ( reader );
Symbol symbol = null;
loop:
while ( ( symbol = calcScanner.nextToken ( ) ).sym != EOF )
{
System.out.println (
"Symbol: " + symbol + " Value: " + symbol.value );
}
}
public static Symbol scanInteger ( String text )
//////////////////////////////////////////////////////////////////////
{
try
{
return new Symbol ( INTEGER, new Integer ( text ) );
}
catch ( NumberFormatException ex )
{
return null;
}
}
//////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////
private java.io.BufferedReader yy_reader;
private int yy_buffer_index;
private int yy_buffer_read;
private int yy_buffer_start;
private int yy_buffer_end;
private char yy_buffer[];
private int yychar;
private int yyline;
private int yy_lexical_state;
public CalcScanner (java.io.Reader reader) {
this ();
if (null == reader) {
throw (new Error("Error: Bad input stream initializer."));
}
yy_reader = new java.io.BufferedReader(reader);
}
public CalcScanner (java.io.InputStream instream) {
this ();
if (null == instream) {
throw (new Error("Error: Bad input stream initializer."));
}
yy_reader = new java.io.BufferedReader(new java.io.InputStreamReader(instream));
}
private CalcScanner () {
yy_buffer = new char[YY_BUFFER_SIZE];
yy_buffer_read = 0;
yy_buffer_index = 0;
yy_buffer_start = 0;
yy_buffer_end = 0;
yychar = 0;
yyline = 0;
yy_lexical_state = YYINITIAL;
}
private boolean yy_eof_done = false;
private final int YYINITIAL = 0;
private final int yy_state_dtrans[] = {
0
};
private void yybegin (int state) {
yy_lexical_state = state;
}
private char yy_advance ()
throws java.io.IOException {
int next_read;
int i;
int j;
if (yy_buffer_index < yy_buffer_read) {
return yy_buffer[yy_buffer_index++];
}
if (0 != yy_buffer_start) {
i = yy_buffer_start;
j = 0;
while (i < yy_buffer_read) {
yy_buffer[j] = yy_buffer[i];
++i;
++j;
}
yy_buffer_end = yy_buffer_end - yy_buffer_start;
yy_buffer_start = 0;
yy_buffer_read = j;
yy_buffer_index = j;
next_read = yy_reader.read(yy_buffer,
yy_buffer_read,
yy_buffer.length - yy_buffer_read);
if (-1 == next_read) {
return YYEOF;
}
yy_buffer_read = yy_buffer_read + next_read;
}
while (yy_buffer_index >= yy_buffer_read) {
if (yy_buffer_index >= yy_buffer.length) {
yy_buffer = yy_double(yy_buffer);
}
next_read = yy_reader.read(yy_buffer,
yy_buffer_read,
yy_buffer.length - yy_buffer_read);
if (-1 == next_read) {
return YYEOF;
}
yy_buffer_read = yy_buffer_read + next_read;
}
return yy_buffer[yy_buffer_index++];
}
private void yy_move_start () {
if ((byte) '\n' == yy_buffer[yy_buffer_start]) {
++yyline;
}
++yychar;
++yy_buffer_start;
}
private void yy_pushback () {
--yy_buffer_end;
}
private void yy_mark_start () {
int i;
for (i = yy_buffer_start; i < yy_buffer_index; ++i) {
if ((byte) '\n' == yy_buffer[i]) {
++yyline;
}
}
yychar = yychar
+ yy_buffer_index - yy_buffer_start;
yy_buffer_start = yy_buffer_index;
}
private void yy_mark_end () {
yy_buffer_end = yy_buffer_index;
}
private void yy_to_mark () {
yy_buffer_index = yy_buffer_end;
}
private java.lang.String yytext () {
return (new java.lang.String(yy_buffer,
yy_buffer_start,
yy_buffer_end - yy_buffer_start));
}
private int yylength () {
return yy_buffer_end - yy_buffer_start;
}
private char[] yy_double (char buf[]) {
int i;
char newbuf[];
newbuf = new char[2*buf.length];
for (i = 0; i < buf.length; ++i) {
newbuf[i] = buf[i];
}
return newbuf;
}
private final int YY_E_INTERNAL = 0;
private final int YY_E_MATCH = 1;
private java.lang.String yy_error_string[] = {
"Error: Internal error.\n",
"Error: Unmatched input.\n"
};
private void yy_error (int code,boolean fatal) {
java.lang.System.out.print(yy_error_string[code]);
java.lang.System.out.flush();
if (fatal) {
throw new Error("Fatal Error.\n");
}
}
private int [][] unpackFromString(int size1, int size2, String st)
{
int colonIndex = -1;
String lengthString;
int sequenceLength = 0;
int sequenceInteger = 0;
int commaIndex;
String workString;
int res[][] = new int[size1][size2];
for (int i= 0; i < size1; i++)
for (int j= 0; j < size2; j++)
{
if (sequenceLength == 0)
{
commaIndex = st.indexOf(',');
if (commaIndex == -1)
workString = st;
else
workString = st.substring(0, commaIndex);
st = st.substring(commaIndex+1);
colonIndex = workString.indexOf(':');
if (colonIndex == -1)
{
res[i][j] = Integer.parseInt(workString);
}
else
{
lengthString = workString.substring(colonIndex+1);
sequenceLength = Integer.parseInt(lengthString);
workString = workString.substring(0,colonIndex);
sequenceInteger = Integer.parseInt(workString);
res[i][j] = sequenceInteger;
sequenceLength--;
}
}
else
{
res[i][j] = sequenceInteger;
sequenceLength--;
}
}
return res;
}
private int yy_acpt[] = {
YY_NOT_ACCEPT,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR,
YY_NO_ANCHOR
};
private int yy_cmap[] = {
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 0, 0, 0, 2, 0, 0,
3, 4, 5, 6, 0, 7, 0, 8,
9, 9, 9, 9, 9, 9, 9, 9,
9, 9, 10, 11, 12, 13, 14, 0,
0, 15, 15, 15, 15, 15, 15, 15,
15, 15, 15, 15, 15, 15, 15, 15,
15, 15, 15, 15, 15, 15, 15, 15,
15, 15, 15, 0, 0, 0, 16, 17,
0, 15, 15, 15, 15, 18, 15, 15,
15, 19, 15, 15, 15, 15, 15, 15,
15, 15, 20, 15, 21, 15, 15, 22,
15, 15, 15, 0, 0, 0, 0, 0
};
private int yy_rmap[] = {
0, 1, 1, 1, 1, 1, 1, 1,
1, 2, 1, 1, 1, 3, 1, 1,
1, 1, 3, 4, 5, 6, 7, 8,
9, 10
};
private int yy_nxt[][] = unpackFromString(11,23,
"1,19,2,3,4,5,6,7,8,9,21,10,11,22,12,13,14,1,13:4,25,-1:32,9,-1:22,13,-1:5,13,-1,13:6,-1:13,15,-1:18,13,-1:5,13,-1,13,18,13:4,-1:13,16,-1:22,17,-1:18,13,-1:5,13,-1,13:4,20,13,-1:9,13,-1:5,13,-1,13:2,23,13:3,-1:9,13,-1:5,13,-1,13:3,24,13:2");
public Symbol nextToken ()
throws java.io.IOException {
char yy_lookahead;
int yy_anchor = YY_NO_ANCHOR;
int yy_state = yy_state_dtrans[yy_lexical_state];
int yy_next_state = YY_NO_STATE;
int yy_last_accept_state = YY_NO_STATE;
boolean yy_initial = true;
int yy_this_accept;
yy_mark_start();
yy_this_accept = yy_acpt[yy_state];
if (YY_NOT_ACCEPT != yy_this_accept) {
yy_last_accept_state = yy_state;
yy_mark_end();
}
while (true) {
yy_lookahead = yy_advance();
yy_next_state = YY_F;
if (YYEOF != yy_lookahead) {
yy_next_state = yy_nxt[yy_rmap[yy_state]][yy_cmap[yy_lookahead]];
}
if (YY_F != yy_next_state) {
yy_state = yy_next_state;
yy_initial = false;
yy_this_accept = yy_acpt[yy_state];
if (YY_NOT_ACCEPT != yy_this_accept) {
yy_last_accept_state = yy_state;
yy_mark_end();
}
}
else {
if (YYEOF == yy_lookahead && true == yy_initial) {
return new Symbol ( EOF );
}
else if (YY_NO_STATE == yy_last_accept_state) {
throw (new Error("Lexical Error: Unmatched Input."));
}
else {
yy_to_mark();
yy_anchor = yy_acpt[yy_last_accept_state];
if (0 != (YY_END & yy_anchor)) {
yy_pushback();
}
if (0 != (YY_START & yy_anchor)) {
yy_move_start();
}
switch (yy_last_accept_state) {
case 1:
{ yybegin ( YYINITIAL ); }
case -2:
break;
case 2:
{ return new Symbol ( MOD ); }
case -3:
break;
case 3:
{ return new Symbol ( LPAREN ); }
case -4:
break;
case 4:
{ return new Symbol ( RPAREN ); }
case -5:
break;
case 5:
{ return new Symbol ( TIMES ); }
case -6:
break;
case 6:
{ return new Symbol ( PLUS ); }
case -7:
break;
case 7:
{ return new Symbol ( MINUS ); }
case -8:
break;
case 8:
{ return new Symbol ( DIVIDE ); }
case -9:
break;
case 9:
{ return scanInteger ( yytext ( ) ); }
case -10:
break;
case 10:
{ return new Symbol ( SEMICOLON ); }
case -11:
break;
case 11:
{ return new Symbol ( LT ); }
case -12:
break;
case 12:
{ return new Symbol ( GT ); }
case -13:
break;
case 13:
{ return new Symbol ( VARIABLE, yytext ( ) ); }
case -14:
break;
case 14:
{ return new Symbol ( EXP ); }
case -15:
break;
case 15:
{ return new Symbol ( NEQ ); }
case -16:
break;
case 16:
{ return new Symbol ( ASSIGN ); }
case -17:
break;
case 17:
{ return new Symbol ( EQ ); }
case -18:
break;
case 18:
{ return new Symbol ( WRITE ); }
case -19:
break;
case 19:
{ yybegin ( YYINITIAL ); }
case -20:
break;
case 20:
{ return new Symbol ( VARIABLE, yytext ( ) ); }
case -21:
break;
case 21:
{ yybegin ( YYINITIAL ); }
case -22:
break;
case 22:
{ yybegin ( YYINITIAL ); }
case -23:
break;
case 23:
{ return new Symbol ( VARIABLE, yytext ( ) ); }
case -24:
break;
case 24:
{ return new Symbol ( VARIABLE, yytext ( ) ); }
case -25:
break;
case 25:
{ return new Symbol ( VARIABLE, yytext ( ) ); }
case -26:
break;
default:
yy_error(YY_E_INTERNAL,false);
case -1:
}
yy_initial = true;
yy_state = yy_state_dtrans[yy_lexical_state];
yy_next_state = YY_NO_STATE;
yy_last_accept_state = YY_NO_STATE;
yy_mark_start();
yy_this_accept = yy_acpt[yy_state];
if (YY_NOT_ACCEPT != yy_this_accept) {
yy_last_accept_state = yy_state;
}
}
}
}
}
}
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