Sawaal

 Technology Questions

Popular Latest Rated
Q:

What is the difference between an Interface and an Abstract class ?

Answer

1.Main difference is methods of a Java interface are implicitly abstract and cannot have implementations. A Java abstract class can have instance methods that implements a default behavior.


2.Variables declared in a Java interface is by default final. An abstract class may contain non-final variables.


3.Members of a Java interface are public by default. A Java abstract class can have the usual flavors of class members like private, protected, etc..


4.Java interface should be implemented using keyword “implements”; A Java abstract class should be extended using keyword “extends”.


5.An interface can extend another Java interface only, an abstract class can extend another Java class and implement multiple Java interfaces.


6.A Java class can implement multiple interfaces but it can extend only one abstract class.


7.Interface is absolutely abstract and cannot be instantiated; A Java abstract class also cannot be instantiated, but can be invoked if a main() exists.


8.In comparison with java abstract classes, java interfaces are slow as it requires extra indirection.

Report Error

View answer Workspace Report Error Discuss

Subject: Java

0 2311
Q:

What are PL/SQL cursor exceptions?

Answer

Cursor_Already_Open,  Invalid_Cursor.

Report Error

View answer Workspace Report Error Discuss

Subject: SQL

0 2308
Q:

What is JAR file?

Answer

A JAR file (short for Java Archive) is a ZIP file used to distribute a set of Java classes. It is used to store compiled Java classes and associated metadata that can constitute a program

Report Error

View answer Workspace Report Error Discuss

Subject: Java

0 2307
Q:

What is the purpose of overriding toString() method?

Answer

we can override tostring() method to return String representation of our object data

Report Error

View answer Workspace Report Error Discuss

Subject: Java

0 2306
Q:

What is the importance of Doctype in HTML?

Answer

Doctype tag is not a HTML tag, it is just an instruction that is passed to the web browser to check for the information that is being provided by the markup language in which the page is written. Doctype is sometimes referred as Document type definition (DTD) that describes some rules that has to be followed while writing the markup language so to make the web browser understand the language and the content correctly. Doctype is very important to be placed in the beginning of the HTML and before the <HTML> tag to allow easy rendering of the pages that are used.

Report Error

View answer Workspace Report Error Discuss

Subject: Web Technology

1 2302
Q:

What are instance variables?

Answer Instance variables are those which are defined at the class level. Instance variables need not be initialized before using them as they are automatically initialized to their default values.
Report Error

View answer Workspace Report Error Discuss

Subject: Java

0 2302
Q:

What is BAS? What is its function ?

Answer

The Business Application Support (BAS) functional area at SLAC provides administrative computing services to the Business Services Division and Human Resources Department. We are responsible for software development and maintenance of the PeopleSoft applications and consultation to customers with their computer-related tasks.


It's called Broadcast Agent Server. Its function is torun the jobs or reports scheduled and can be monitored using Broadcast Agent Console.

Report Error

View answer Workspace Report Error Discuss

Subject: Business Intelligence

0 2301
Q:

what is the use of virtual destructor in c++?

Answer

A destructor is automatically called when the object is destroyed. A virtual destructor in C++ is used primarily to prevent resource leaks by performing a clean-up of the object.

Report Error

View answer Workspace Report Error Discuss

Subject: C++

0 2300