Essential Java Interview Questions and Answers
Java Super Keyword
Question: Explain the functionality of the super keyword in Java.
Answer: The super keyword refers to the immediate parent class object. It is used to:
- Access parent class data members hidden by child class data members.
- Call parent class methods when overridden in the child class.
- Invoke the parent class constructor using
super().
Throw vs Throws in Java
Question: Differentiate between throw and throws keywords in Java.
Answer: throw is used inside a method or block to explicitly throw
ARM LPC1768 Embedded C Programming and Architecture
ARM LPC1768 Embedded C Programming Examples
LED Blinking Program for ARM LPC1768
#include <LPC17xx.h>
void delay() {
for(int i=0; i<1000000; i++);
}
int main(void) {
LPC_GPIO2->FIODIR |= (1<<0); // Set P2.0 as output
while(1) {
LPC_GPIO2->FIOSET = (1<<0); // LED ON
delay();
LPC_GPIO2->FIOCLR = (1<<0); // LED OFF
delay();
}
}Switch Controlled LED Interfacing
#include <LPC17xx.h>
int main(void) {
LPC_GPIO2- Read More
Node.js and Express Backend Development Handbook
Express Framework Fundamentals
The Node.js web framework provides a structured pipeline from top to bottom:
- Routing system
- Middleware pipeline
- Response utilities
- Template integration (Pug, etc.)
The standard flow follows: Request → Middleware → Route → Response.
Middleware Pipeline
Middleware functions run before the final response. The function signature is (req, res, next). These functions can:
- Modify the req or res objects.
- Stop the request using
res.send(). - Pass control using
next().
Note: If neither
Read MoreFundamental Concepts of Computing and Programming
Definition and Characteristics of a Computer
A computer is an electronic device that accepts data (input), processes it according to a set of instructions (program), stores it, and produces meaningful information (output).
What is a Computer?
A computer can be defined as: “An electronic machine that takes input, processes it under the control of a program, and produces output while storing the data for future use.”
Key Characteristics of a Computer
Computers have several important characteristics
Read MoreWindows Server Administration: Essential PowerShell & Tasks
Remote PowerShell
Enter-PSSession -ComputerName AcmeDCExit-PSSession
Create Security Group
New-ADGroup -Name "NAME" -GroupScope Global -Path "OU=Hamilton,DC=acme,DC=com"
Create Folder and Share
- Folder:
New-Item -Path "C:\Corporate\NAME" -ItemType Directory - Share:
New-SmbShare -Name "NAME" -Path "C:\Corporate\NAME" -FullAccess "Everyone"
NTFS Permissions (icacls)
- Full Control:
icacls "PATH" /grant "ACME\GROUP:(OI)(CI)F" - Modify:
icacls "PATH" /grant "ACME\GROUP:(OI)(CI)M" - Read & Exec:
icacls "PATH" /grant
PPS SEMII
1. Short note on String
A String is a one-dimensional array of characters terminated by a null(‘\0’). Each character in the array occupies one byte of memory, and the last character
must always be null(‘\0’). The termination character (‘\0’) is important in a string to identify where the string
ends.
Syntax:
charstring_name[size];
char name[10]; [0] [1] [2] [3] [4] [5] [6] [7] [8] [9]
name[10 D A R S H A N \0
Declaration and Initialisation
You can declare and
