Question

1.Write EBNF descriptions for the following:

A) Java class definition statement

B) Java method call statement

C) Java method header

D) C switch statement

E) C++ class declaration statement

F) C# Constructor declaration statement

Answer 1

A) Java class definition

public class A extends B implements C,D

where

public is modifier

A,B,C,D are identifiers

Assume non-terminal id as <id>

The definition becomes

[public] [(final|abstract)] class <id> [extends <id>] [implements <id> {, <id>}]

2) Java method call statement

<for> -> for ‘(‘ [[<type>] <id> = <expr> {, [<type>] <id> = <expr>}] ; [<expr>] ; [<expr>{, <expr>}] ‘)’ ‘{‘ <stmt_list> ‘}’

3)

The following is an example switch statement:

switch (a+b)

{

case 1 : x = 7; break;

case 2 :  x = 8; break;

default : x = 9;

}

where “a+b” is an expression,

“1” and “2” are literals,

and “x=7;break;”, “x=8;break;” and “x=9;” are statement lists.

Assume non-terminals are <expr>, <literal>, and <stmt_list>

<switch> -> switch ‘(‘ <expr> ‘)’ ‘{‘ {case <literal> : <stmt_list>} [default : <stmt_list>] ‘}’