Interview Questions

Autoboxing is the process of converting a primitive type data into its corresponding wrapper class object instance.

Example:

Integer number = new Integer (100); // number is now refers to the object 100

Unboxing is the process of converting a wrapper instance into a primitive type.

Example: 

Integer number = new Integer (100); 

int num = number;// without type casting number would be changed into int type

A table of data representing a database result set, which is usually generated by executing a statement that queries the database.

ResultSet object maintains a cursor pointing to its current row of data. Initially the cursor is positioned before the first row. The next method moves the cursor to the next row, and because it returns false when there are no more rows in the ResultSet object, it can be used in a while loop to iterate through the result set.

Oracle NOT NULL is used on a column to ensure that the value for that column can never be NULL.
Example:
Below, the constraint is that the id should never be NULL. If it is, oracle throws an error.
create table employee ( id number NOT NULL, Name varchar(200) );

The Sales Order is a confirmation document sent to the customers before delivering the goods or services. 

Sales Order (SO) can be created once the quote is accepted by your prospective customer and the Purchase Order (PO) is sent by the customer for further processing.

The JVM performs three main tasks:

• Loads code

• Verifies code

• Executes code

-To store information usually relevant to browsers and search engines.

-To only store information usually relevant to browsers

-To only store information about search engines.

-To store information about external links

- Virtual domain is the domain of the client on which they can run their applications without having to install the server or hardware. 

- The software need not to be installed physically on the server as it can be done using the local repositories and maintaining the domain locally. 

- Using the virtual domain the server storage space is utilized efficiently and the data can be made more secure before publishing it online. 

- Virtual domains are used to represent the personal Internet web address domain name and can be made with your personal one. 

- Virtual domain provides more security in terms of using your own personalized domain and allows the access to the resources that are on web.

CDATA - (Unparsed) Character Data

The term CDATA is used when you dont want some text data to be parsed by the XML parser.

A CDATA section starts with "<![CDATA[" and ends with "]]>":