Technology Questions

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.

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

An app will be in InActive state if it is running in the foreground but is currently not receiving events. An app stays in InActive state only briefly as it transitions to a different state.

Wrapped classes are classes that allow primitive types to be accessed as objects.

Top level class is also called outer class. It is not defined inside any class.

Ex:

class A {  //top level class

}

Group of tables physically stored together because they share common columns and are often used together is called Cluster.

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.

If we print any object by using println() or print() methods.

The println() or print() methods internally calls tostring() method and prints the return value of toString() method.