BNF.txt

                Goal	::=	MainClass ( ClassDeclaration )* <EOF>
        MainClass	::=	"class" Identifier "{" "public" "static" "void" "main" "(" "String" "[" "]" Identifier ")" "{" Statement "}" "}"
ClassDeclaration	::=	"class" Identifier ( "extends" Identifier )? "{" ( VarDeclaration )* ( MethodDeclaration )* "}"
        VarDeclaration	::=	Type Identifier ";"
MethodDeclaration	::=	"public" Type Identifier "(" ( Type Identifier ( "," Type Identifier )* )? ")" "{" ( VarDeclaration )* ( Statement )* "return" Expression ";" "}"
                Type	::=	"int" "[" "]"
                        |	"boolean"
                        |	"int"
                        |	Identifier
        Statement	::=	"{" ( Statement )* "}"
                        |	"if" "(" Expression ")" Statement "else" Statement
                        |	"while" "(" Expression ")" Statement
                        |	"System.out.println" "(" Expression ")" ";"
                        |	Identifier "=" Expression ";"
                        |	Identifier "[" Expression "]" "=" Expression ";"
        Expression	::=	Expression ( "&&" | "<" | "+" | "-" | "*" ) Expression
                        |	Expression "[" Expression "]"
                        |	Expression "." "length"
                        |	Expression "." Identifier "(" ( Expression ( "," Expression )* )? ")"
                        |	<INTEGER_LITERAL>
                        |	"true"
                        |	"false"
                        |	Identifier
                        |	"this"
                        |	"new" "int" "[" Expression "]"
                        |	"new" Identifier "(" ")"
                        |	"!" Expression
                        |	"(" Expression ")"
        Identifier	::=	<IDENTIFIER>