Interview Questions

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.

READNEXT reads the next record from a browse operation for any of the three VSAM files.

- The process of combining data from different resources.

- The combined data is provided to the users with unified view.

- Information from different enterprise domains are integrated – known as Enterprise Information Integration.

- Useful for merging information from different technologies among enterprises.

- The sub areas of data integration are 

1. Data Warehousing.

2. Data Migration.

3. Master Data Management.

public class Test {

    public void replaseSpaces(char[] str, int length) {

        int spaceCount = 0, newLength = 0, i = 0;

        for(i = 0; i < length; i++) {

            if (str[i] == ' ') 

                spaceCount++;

        }

        newLength = length + (spaceCount * 2);

        str[newLength] = '\0';

        for(i = length - 1; i >= 0; i--) {

            if (str[i] == ' ') {

                str[newLength - 1] = '0';

                str[newLength - 2] = '2';

                str[newLength - 3] = '%';

                newLength = newLength - 3;

            }

            else {

                str[newLength - 1] = str[i];

                newLength = newLength - 1;

            }

        }

        System.out.println(str);

    }

    public static void main(String[] args) {

        Test tst = new Test();

        char[] ch = {'t', 'h', 'e', ' ', 'd', 'o', 'g', ' ', ' ', ' ', ' ', ' ', ' '};

        int length = 6;

        tst.replaseSpaces(ch, length);  

    }

}

AWB stands for Administrator WorkBench. AWB is a tool for controlling, monitoring and maintaining all the processes connected with data staging and processing in the business information whearhousing.

Oracle constraints are used to maintain consistent of data and ensure the data is properly maintained. A constraint is more or less a restriction we try to apply on a table.
Types of constraints:
- Check constraints
- NOT NULL constraint
- PRIMARY KEY constraint
- REFERENCES constraint
- UNIQUE constraint

The System.Collections namespace contains all the collection classes.

A web application resides in the server and serves the client’s requests over internet. The client access the web page using browser from his machine. When a client makes a request, it receives the result in the form of HTML which are interpreted and displayed by the browser.

A web application on the server side runs under the management of Microsoft Internet Information Services (IIS). IIS passes the request received from client to the application. The application returns the requested result in the form of HTML to IIS, which in turn, sends the result to the client.