Technology 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

SQL statement gets executed when we open cursor

Session storage is same like local storage but the data is valid for a session. In simple words the data is deleted as soon as you close the browser.

To create a session storage you need to use “sessionStorage.variablename” . In the below code we have a created a variable called as “clickcount”.

If you refresh the browser the count increases. But if you close the browser and start again the “clickcount” variable starts from zero.

if(sessionStorage.clickcount)

{

sessionStorage.clickcount=Number(sessionStorage.clickcount)+1;

}

else

{

sessionStorage.clickcount = 0;

} 

A thread is a lightweight subprocess, a smallest unit of processing. It is a separate path of execution. It shares the memory area of process.

As shown in the above figure, thread is executed inside the process. There is context-switching between the threads. There can be multiple processes inside the OS and one process can have multiple threads.

We can use the following method call:

boolean createNewFile();

This method creates a new file on the HD. 

If a file is already existing with the name given in the constructor then this method does not creates file on HD.

If file is successfully created then this method returns true.

If file is already existing on the HD then this method returns false.

This method may throw IOException whenever IO error is generated while creating file on HD.

By using overloading we can add new functionality to the sub class.

advantages: view is used to retrieve the data very fastly from the database tables
* memory wastage is reduced
* faster than joins to retrieve the data from database tables

disadvantages:
* view is not a container,it will not hold the data
* view memory is not permanent memory

FDM is an analog technique that can be applied when the bandwidth of a link is greater than the combined bandwidths of the signals to be transmitted.