JAVA eclipse different ways implement INTERFACE

interface MyInterface {
	void sayHello();

class ClassOne {
	static void methodThatCallInterfaceMethod(MyInterface i) {

class ClassTwo implements MyInterface {
	static void sayGoodBye() {
		System.out.println("hi - for METHOD REFERENCE CALLING");

	public void sayHello() {
		// TODO Auto-generated method stub

	MyInterface getMyInterface() {
		return this;

class ClassThree {
	static ClassTwo getInstanceOfClassTwo() {
 		return new ClassTwo();

public class Main implements MyInterface {
	public static void main(String[] args) {
		Main InstanceOfMain = new Main();
		//METHOD 1
		//METHOD 2
		ClassOne.methodThatCallInterfaceMethod(new Main());
		//METHOD 3
		ClassOne.methodThatCallInterfaceMethod(new MyInterface() {
			public void sayHello() {
				// TODO Auto-generated method stub
				System.out.println("Good morning from INNER CLASS");
		//METHOD 4
		ClassOne.methodThatCallInterfaceMethod(() -> System.out.println("Hi from LAMBDA IMPLEMENTATION"));
		//METHOD 5
		ClassTwo InstanceClassTwo = new ClassTwo();
		//METHOD 6
		//METHOD 7
		//METHOD 8
		MyInterface instanceCreatedToStoreAnnonymousInnerClass = new MyInterface() {

			public void sayHello() {
				// TODO Auto-generated method stub
				System.out.println("hi from ANNONYMOUS INNER CLAS ASIGNED TO VARIABLE");

	void methodInsideMainClass () {
		System.out.println("hi from CLASS INSIDE MAIN CLASS");

	void methodThatServeAsABridgeToExecuteinMainStaticMethod() {

	public void sayHello() {
		// TODO Auto-generated method stub
		System.out.println("hi from Main INSIDE CLASS");

Oracle SQL Developer

SQL Developer help enter a substitution variable

«Insert into CSE_DEPT.COURSE (COURSE_ID,COURSE,CREDIT,CLASSROOM,SCHEDULE,ENROLLMENT,FACULTY_ID) values (‘CSE-334′,’Elec. Measurement & Design’,3,’TC-212′,’T-H: 11:00-12:25 PM’,25,’H99118′);»
In SQL , » &» is interpreted as the beginning of a substitution variable .

3 possible solutions :

SET ESPACE ‘\’ , and use ‘\’ to scape & in you code exp: \&
SET SCAN OFF , disable scanning for substitution variables

SET DEFINE OFF; turn off substitution completely

launch VIM from Command Prompt windows 10

after instal vim , there is a problem to launch vim from command prompt

we have to add a path to our user variables , first have to find folder where is our vim executable …

go to «environment variables»

edit «path» in user variables , ADD the folder where is you vim executable (there many other paths inside )

Determine current DNS resolver service

to flush/clean DNS , have to know your DNS resolver service

cat /etc/resolv.conf

«systemd-resolve» and «systemd-resolved» ARE NOT THE SAME

«systemd-resolve» is a command line tool for interacting with the «systemd-resolved» service and «systemd-resolved» is the actual DNS resolver service

now you can see DNS cache information , you can use this command «systemd-resolve –statistics»

sudo systemd-resolve –flush-caches

sudo systemctl restart systemd-resolved

these two commands fusl complety DNS cache ,

after run two commands above

Cisco Packet Tracer 8.2 (64 bit)

Download resource

cd Downloads

sudo dpkg -i filename.deb

#run following command if there is some error during installation

sudo apt –fix-broken install

#to fix some error during installation about dependencies , run following

sudo apt install -f

to launch the packet or simply run it in programms (superkey+a )


for first time launch app , (skill for all option , green option )require login , «back» and then redirect to a browser tab , note that there are options below «login with google or cisco» , choose login with «cisco» and use «cisco» already ( for download its been required ) registered account …