CS 696 Emerging Technologies: Distributed Objects

1. References
   1. Overview
   2. Module
   3. Interface
   4. Basic Data Types
   5. Basic Data Types - Java Mappings

Doc 20, CORBA IDL Slide # 2

/* standard C/C++  comments
*/

// standard C++ comments

Doc 20, CORBA IDL Slide # 3

12

014

0XC

8 bit with value between 0 and 255

Uses ISO Latin-1 character set

---

Doc 20, CORBA IDL Slide # 4

123.321e12

123.321E12

123.321

.123

123.

123.321d

123.321D

.123d

123.d

Doc 20, CORBA IDL Slide # 5

"hi Mom"

Adjacent literals are concatenated

"this is""a test" = "this isa test"

Characters in concatenated strings are kept distinct

"\xA""B"

has two characters after concatenation: '\xA' and 'B'

A string literal may not contain '\0' (zero)

Doc 20, CORBA IDL Slide # 6

module Bank
   {
   interface Account
      {
      readonly attribute float balance;
      };
   };         // yes you need these semi-colons

//
// Java generated by the OrbixWeb IDL compiler
//

package Bank;


public interface Account
    extends org.omg.CORBA.Object
{
    public float balance();

    public java.lang.Object _deref() ;
}
Doc 20, CORBA IDL Slide # 7

module Bank
   {
   interface Account
      {
      readonly attribute float balance;
      };
   };         // yes you need these ';'

module Security
   {
   interface Algorithms
      {
      string MD5(in float data);
      
      // using the scoping operator here
      Bank::Account idToAccount( in string id);
      };
   };
   
// reopening the Bank module
module Bank
   {
   interface Teller
      {
      Account getAccount( in string customerID );
      };
   };
Doc 20, CORBA IDL Slide # 8

module sdsu
   {
   module whitney
      {
      module cs696
         {
         interface ReportCard
            {
            readonly attribute short grade;
            };
         };
      };
   };

module Bank
   {
   // Forward declare customer
   interface Customer;
   
   interface Account
      {
      Customer getOwner();
      };
   interface Customer
      {
      Account getAccount();
      }
   };
Doc 20, CORBA IDL Slide # 9

interface Account
   {
   readonly attribute float balance;
   };

supports multiple inheritance

contains:

type declarations

constants declarations

exception declarations

attributes declarations

operations declarations

Doc 20, CORBA IDL Slide # 10

interface Right {
   string getRightMessage(in string ID);
};

interface Left {
   string getLeftMessage(in string ID);
};

interface Bottom : Right, Left {
   readonly attribute short lecture;
};

Doc 20, CORBA IDL Slide # 11

IDL Type	Range
short	(16 bit)
unsigned short	(16 bit)
long	(32 bit)
unsigned long	(32 bit)
long long	(64 bit)
unsigned long long	(64 bit)
float	IEEE single-precision floating point
double	IEEE double-precision floating point
long double	IEEE double-extended floating point
char	8-bit value
wchar	16 bit value
boolean	TRUE or FALSE
octet	8-bit
any
string
wstring

An 8-bit quantity which is guaranteed not to undergo any conversion when transmitted by the communication system

Doc 20, CORBA IDL Slide # 12

encodes a single-byte character from any byte-oriented code set

or

when used in an array, encodes a multi-byte character from a multi-byte code set

In other words, an implementation is free to use any code set internally for encoding character data

The ISO 8859-1 (Latin1) character set standard defines the meaning of and representation of all possible graphic characters used in OMG IDL

During transmission may be converted to different form, but a character's meaning can not be changed

encodes wide characters from any character set

An implementation is free to use any code set internally

The size of wchar is implementation-dependent

During transmission may be converted to different form, but a character's meaning can not be changed

Doc 20, CORBA IDL Slide # 13

Java does not support unsigned values

Programmer must insure that unsigned types are in the proper range

Doc 20, CORBA IDL Slide # 14

Java char' are 16 bit

If a Java char is sent to a OMG IDL char and is not in the proper range a CORBA::DATA_CONVERSTION exception will be thrown

Java strings are made up of 16 bit chars

If a Java string is sent to a OMG IDL string and a char is not in the proper range a CORBA::DATA_CONVERSTION exception will be thrown

CORBA::MARSHAL exceptions can also be thrown in converting between java.lang.String and OMG IDL string

CORBA::MARSHAL exception can also be thrown in converting between java.lang.String and wstring

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