Technology Questions

"==" checks equality only,
"===" checks for equality as well as the type.

new ClassName( arg1, arg2, .... argN);

Ex:

Class sample {

   Sample(int a) {

   System.out.println("arg con a =" +a);

   }

}

class Demo {

    Public static void main( String[] args) {

     Sample s1= new Sample(23);

     Sample s2= new Sample(45);

    }

}

Call Transaction Method: In Call Transaction method we call the transaction in BDC program itself. If we want this program is executed by some one else then we need to expose the code to him. Call Transaction Method Works in Foreground. No Display Mode is equal to Background Processing in call transaction method. Call Transaction Method can handle only one Application at a time. In Call Transaction Method no Log File by Default. We have to design Log File by using BDCMSGCOLL. Call Transaction Method Updates the Database Asynchronously. (Note: Asynchronous updation is Faster than Synchronous)
 
Batch Session Method: On the other hand in batch session method we create a session which can be executed at any time by any authorized person without exposing the code of the program. Session Method works in Background and as well as in Foreground. Session Method can handle Multiple Applications at a time. Session Method holds Log File by Default. Session Method Updates the Database Synchronously.

We need to first login to the data base as: SQLPLUS followed by user_name/password. Then we need to execute the following query:

CREATE USER user_name IDENTIFIED BY abcd; in this query a user_name suggest the user that is created which has a password abcd which is required for login in database.

- The Set interface provides methods for accessing the elements of a finite mathematical set

- Sets do not allow duplicate elements

- Contains no methods other than those inherited from Collection

- It adds the restriction that duplicate elements are prohibited

- Two Set objects are equal if they contain the same elements

Path contains path of .exe files(commands).

Classpath contains path of packages. packages can be stored in folder or .jar files

The wait(), notify(), and notifyAll() methods are used to provide an efficient way for threads to wait for a shared resource. When a thread executes an object's wait() method, it enters the waiting state. It only enters the ready state after another thread invokes the object's notify() or notifyAll() methods..