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/* Copyright (c) 2006, Sun Microsystems, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the Sun Microsystems, Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
PARSER_BEGIN(Eg1)
/** An Arithmetic Grammar. */
public class Eg1 {
/** Main entry point. */
public static void main(String args[]) {
System.out.println("Reading from standard input...");
Eg1 t = new Eg1(System.in);
try {
SimpleNode n = t.Start();
n.dump("");
System.out.println("Thank you.");
} catch (Exception e) {
System.out.println("Oops.");
System.out.println(e.getMessage());
e.printStackTrace();
}
}
}
PARSER_END(Eg1)
SKIP :
{
" "
| "\t"
| "\n"
| "\r"
| <"//" (~["\n","\r"])* ("\n"|"\r"|"\r\n")>
| <"/*" (~["*"])* "*" (~["/"] (~["*"])* "*")* "/">
}
TOKEN : /* LITERALS */
{
< INTEGER_LITERAL:
<DECIMAL_LITERAL> (["l","L"])?
| <HEX_LITERAL> (["l","L"])?
| <OCTAL_LITERAL> (["l","L"])?
>
|
< #DECIMAL_LITERAL: ["1"-"9"] (["0"-"9"])* >
|
< #HEX_LITERAL: "0" ["x","X"] (["0"-"9","a"-"f","A"-"F"])+ >
|
< #OCTAL_LITERAL: "0" (["0"-"7"])* >
}
TOKEN : /* IDENTIFIERS */
{
< IDENTIFIER: <LETTER> (<LETTER>|<DIGIT>)* >
|
< #LETTER: ["_","a"-"z","A"-"Z"] >
|
< #DIGIT: ["0"-"9"] >
}
/** Main production. */
SimpleNode Start() : {}
{
Expression() ";"
{ return jjtThis; }
}
/** An Expression. */
void Expression() : {}
{
AdditiveExpression()
}
/** An Additive Expression. */
void AdditiveExpression() : {}
{
MultiplicativeExpression() ( ( "+" | "-" ) MultiplicativeExpression() )*
}
/** A Multiplicative Expression. */
void MultiplicativeExpression() : {}
{
UnaryExpression() ( ( "*" | "/" | "%" ) UnaryExpression() )*
}
/** A Unary Expression. */
void UnaryExpression() : {}
{
"(" Expression() ")" | Identifier() | Integer()
}
/** An Identifier. */
void Identifier() : {}
{
<IDENTIFIER>
}
/** An Integer. */
void Integer() : {}
{
<INTEGER_LITERAL>
}
|
