Fredy  Larson

Fredy Larson

1599541620

Why the Instance Variable of the Super Class Is Not Overridden in the Sub Class

When we create a variable in both parent and child classes with the same name and try to access it using a parent’s class reference, which is holding a child class’s object, then what do we get?

In order to understand this, let us consider the example below where we declare a variable x with the same name in both Parent and Child classes.

class Parent {
// Declaring instance variable by name `x`
    String x = "Parent`s Instance Variable";
public void print() {
        System.out.println(x);
}
}

class Child extends Parent {

    // Hiding Parent class's variable `x` by defining a variable in child class with same name.
String x = "Child`s Instance Variable";
    @Override
public void print() {
        System.out.print(x);
    // If we still want to access variable from super class, we do that by using `super.x`
        System.out.print(", " + super.x + "\n");
}
}
```

And now, if we try to access `x` using below code, `System.out.println(parent.x)` will print:

```
Parent parent = new Child();

System.out.println(parent.x) // Output – Parent`s Instance Variable


Well generally, we say that the `Child` class will override the variable declared in the `Parent` class, and `parent.x` will give us whatever the `Child`'s object is holding. Because it is the same thing, it happens while we do the same kind of operation on methods.

But, actually, it is not, and the `parent.x` will give us the value of the Parent`s Instance Variable, which is declared in the `Parent` class — but why?

This is because variables in Java do not follow polymorphism and overriding is only applicable to methods, not variables. And when an instance variable in a `child` class has the same name as an instance variable in a `parent` class, then the instance variable is chosen from the reference type.

In Java, when we define a variable in a `Child` class with a name that we have already used to define a variable in the `Parent` class, the Child class's variable hides the parent's variable, even if their types are different. And this concept is known as **variable hiding**.

In other words, when the `child` and `parent` class both have a variable with the same name, the `Child` class's variable hides the `Parent` class's variable. You can read more on variable hiding in the article: [What is Variable Shadowing and Hiding in Java](https://programmingmitra.com/2018/02/what-is-variable-shadowing-and-hiding.html).

#java #tutorial #overriding #method overriding #variable hiding #sub class #super class

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Buddha Community

Why the Instance Variable of the Super Class Is Not Overridden in the Sub Class
Lawrence  Lesch

Lawrence Lesch

1662107520

Superdom: Better and Simpler ES6 DOM Manipulation

Superdom

You have dom. It has all the DOM virtually within it. Use that power:

// Fetch all the page links
let links = dom.a.href;

// Links open in a new tab
dom.a.target = '_blank';

Only for modern browsers

Getting started

Simply use the CDN via unpkg.com:

<script src="https://unpkg.com/superdom@1"></script>

Or use npm or bower:

npm|bower install superdom --save

Select

It always returns an array with the matched elements. Get all the elements that match the selector:

// Simple element selector into an array
let allLinks = dom.a;

// Loop straight on the selection
dom.a.forEach(link => { ... });

// Combined selector
let importantLinks = dom['a.important'];

There are also some predetermined elements, such as id, class and attr:

// Select HTML Elements by id:
let main = dom.id.main;

// by class:
let buttons = dom.class.button;

// or by attribute:
let targeted = dom.attr.target;
let targeted = dom.attr['target="_blank"'];

Generate

Use it as a function or a tagged template literal to generate DOM fragments:

// Not a typo; tagged template literals
let link = dom`<a href="https://google.com/">Google</a>`;

// It is the same as
let link = dom('<a href="https://google.com/">Google</a>');

Delete elements

Delete a piece of the DOM

// Delete all of the elements with the class .google
delete dom.class.google;   // Is this an ad-block rule?

Attributes

You can easily manipulate attributes right from the dom node. There are some aliases that share the syntax of the attributes such as html and text (aliases for innerHTML and textContent). There are others that travel through the dom such as parent (alias for parentNode) and children. Finally, class behaves differently as explained below.

Get attributes

The fetching will always return an array with the element for each of the matched nodes (or undefined if not there):

// Retrieve all the urls from the page
let urls = dom.a.href;     // #attr-list
  // ['https://google.com', 'https://facebook.com/', ...]

// Get an array of the h2 contents (alias of innerHTML)
let h2s = dom.h2.html;     // #attr-alias
  // ['Level 2 header', 'Another level 2 header', ...]

// Get whether any of the attributes has the value "_blank"
let hasBlank = dom.class.cta.target._blank;    // #attr-value
  // true/false

You also use these:

  • html (alias of innerHTML): retrieve a list of the htmls
  • text (alias of textContent): retrieve a list of the htmls
  • parent (alias of parentNode): travel up one level
  • children: travel down one level

Set attributes

// Set target="_blank" to all links
dom.a.target = '_blank';     // #attr-set
dom.class.tableofcontents.html = `
  <ul class="tableofcontents">
    ${dom.h2.map(h2 => `
      <li>
        <a href="#${h2.id}">
          ${h2.innerHTML}
        </a>
      </li>
    `).join('')}
  </ul>
`;

Remove an attribute

To delete an attribute use the delete keyword:

// Remove all urls from the page
delete dom.a.href;

// Remove all ids
delete dom.a.id;

Classes

It provides an easy way to manipulate the classes.

Get classes

To retrieve whether a particular class is present or not:

// Get an array with true/false for a single class
let isTest = dom.a.class.test;     // #class-one

For a general method to retrieve all classes you can do:

// Get a list of the classes of each matched element
let arrays = dom.a.class;     // #class-arrays
  // [['important'], ['button', 'cta'], ...]

// If you want a plain list with all of the classes:
let flatten = dom.a.class._flat;     // #class-flat
  // ['important', 'button', 'cta', ...]

// And if you just want an string with space-separated classes:
let text = dom.a.class._text;     // #class-text
  // 'important button cta ...'

Add a class

// Add the class 'test' (different ways)
dom.a.class.test = true;    // #class-make-true
dom.a.class = 'test';       // #class-push

Remove a class

// Remove the class 'test'
dom.a.class.test = false;    // #class-make-false

Manipulate

Did we say it returns a simple array?

dom.a.forEach(link => link.innerHTML = 'I am a link');

But what an interesting array it is; indeed we are also proxy'ing it so you can manipulate its sub-elements straight from the selector:

// Replace all of the link's html with 'I am a link'
dom.a.html = 'I am a link';

Of course we might want to manipulate them dynamically depending on the current value. Just pass it a function:

// Append ' ^_^' to all of the links in the page
dom.a.html = html => html + ' ^_^';

// Same as this:
dom.a.forEach(link => link.innerHTML = link.innerHTML + ' ^_^');

Note: this won't work dom.a.html += ' ^_^'; for more than 1 match (for reasons)

Or get into genetics to manipulate the attributes:

dom.a.attr.target = '_blank';

// Only to external sites:
let isOwnPage = el => /^https?\:\/\/mypage\.com/.test(el.getAttribute('href'));
dom.a.attr.target = (prev, i, element) => isOwnPage(element) ? '' : '_blank';

Events

You can also handle and trigger events:

// Handle click events for all <a>
dom.a.on.click = e => ...;

// Trigger click event for all <a>
dom.a.trigger.click;

Testing

We are using Jest as a Grunt task for testing. Install Jest and run in the terminal:

grunt watch

Download Details:

Author: franciscop
Source Code: https://github.com/franciscop/superdom 
License: MIT license

#javascript #es6 #dom 

Fredy  Larson

Fredy Larson

1599541620

Why the Instance Variable of the Super Class Is Not Overridden in the Sub Class

When we create a variable in both parent and child classes with the same name and try to access it using a parent’s class reference, which is holding a child class’s object, then what do we get?

In order to understand this, let us consider the example below where we declare a variable x with the same name in both Parent and Child classes.

class Parent {
// Declaring instance variable by name `x`
    String x = "Parent`s Instance Variable";
public void print() {
        System.out.println(x);
}
}

class Child extends Parent {

    // Hiding Parent class's variable `x` by defining a variable in child class with same name.
String x = "Child`s Instance Variable";
    @Override
public void print() {
        System.out.print(x);
    // If we still want to access variable from super class, we do that by using `super.x`
        System.out.print(", " + super.x + "\n");
}
}
```

And now, if we try to access `x` using below code, `System.out.println(parent.x)` will print:

```
Parent parent = new Child();

System.out.println(parent.x) // Output – Parent`s Instance Variable


Well generally, we say that the `Child` class will override the variable declared in the `Parent` class, and `parent.x` will give us whatever the `Child`'s object is holding. Because it is the same thing, it happens while we do the same kind of operation on methods.

But, actually, it is not, and the `parent.x` will give us the value of the Parent`s Instance Variable, which is declared in the `Parent` class — but why?

This is because variables in Java do not follow polymorphism and overriding is only applicable to methods, not variables. And when an instance variable in a `child` class has the same name as an instance variable in a `parent` class, then the instance variable is chosen from the reference type.

In Java, when we define a variable in a `Child` class with a name that we have already used to define a variable in the `Parent` class, the Child class's variable hides the parent's variable, even if their types are different. And this concept is known as **variable hiding**.

In other words, when the `child` and `parent` class both have a variable with the same name, the `Child` class's variable hides the `Parent` class's variable. You can read more on variable hiding in the article: [What is Variable Shadowing and Hiding in Java](https://programmingmitra.com/2018/02/what-is-variable-shadowing-and-hiding.html).

#java #tutorial #overriding #method overriding #variable hiding #sub class #super class

Yashi Tyagi

1617449307

CA Classes - Best CA Classes Online

Chartered Accountancy course requires mental focus & discipline, coaching for CA Foundation, CA Inter and CA Finals are omnipresent, and some of the best faculty’s classes have moved online, in this blog, we are going to give the best way to find online videos lectures, various online websites provide the CA lectures, Smartnstudy one of the best site to CA preparation, here all faculty’s video lecture available.

check here : ca classes

#ca classes online #ca classes in delhi #ca classes app #ca pendrive classes #ca google drive classes #best ca classes online

Super Affiliate System Review - Recommended or Not?

Is it worth your money?

John Crestani created the Super Affiliate System, an ideal program to equip people with information and skills to achieve affiliate marketing success. In this system, learners need to participate in a module-based learning setting that will help them get started with affiliate marketing by using a simplified system that consists of a single website, buyers, and regular quality traffic. Go through the super affiliate system review to find out more!

John Crestanis’s extensive knowledge and skills in this industry set the Super Affiliate System far apart from competitor affiliate marketing systems. But is the Super Affiliate Commission System a genuine deal? Is it worth investing in? Today, in this Super Affiliate System review, we will take a look at what the system requires and decide whether it’s a real deal affiliate marketing enthusiasts should invest in.

What is the Super Affiliate System?

This is a complete training course that assists people in becoming successful affiliate marketers. The guide uses videos to lead you through the tools and processes you need to become a super affiliate marketer. The program creator has shared thriving, in-depth strategies to give you a life of freedom if you pay heed to them.

The Super Affiliate System is a training guide to equip you with knowledge and skills in the industry. The system will also allow a list of tools needed for affiliate marketers to fast-track their potential.

Super Affiliate System Review: Pros and Cons

There are a few pros and cons that will enlighten beginner affiliates on whether to consider this system or not. Let’s have a look at them one by one:
Pros:-

The system has extensive and informative, easy to follow modules.

The system is designed in a user-friendly manner, especially for beginners.

Equipped with video tutorials to quickly guide you through the process.

The system gives affiliates niche information to provide them with a competitive advantage.

Equipped with revision sections, weekly questions, and daily assignments to help you grasp all the course ideas.

The system extends clients to a 24/7 support system.

It allows clients to have monthly payment plans that can be suitable for those who can’t bear the price of a single down payment. It offers

clients a lot of bonuses.

Clients are allowed a 60-day Super Affiliate System refund guarantee.

Cons:-

It’s very expensive.

Limited coverage of affiliate networks and niches.

Who created the Super Affiliate System?

John Crestani, a 29-year-old expert in affiliate marketing from Santa Monica, California, is the program’s creator. The veteran left out of college and chose to earn money online since there are low job prospects. He failed several times, striving to make ends meet for quite some time until he successfully built a successful affiliate site dealing with health-related products.
He is currently a seven-figure person making more than $500 per month. His remarkable success in affiliate marketing has made him a featured in Yahoo Finance, Inc., Forbes, Business Insider, and Home Business magazine.

With the enormous success he has seen in affiliate marketing, John has designed an easy-to-follow guide to provide people with the skills to make money as an affiliate marketer. He has described all the strategies and tools he used to lead him to success.

Super Affiliate System Review: Does it Work?

The system accommodates affiliate marketers with in-depth details on how to develop successful affiliate networks. The Super Affiliate System review has a positive impact on different affiliate marketers who have tried it and noticed impressive results. But then, does it work?

The program doesn’t promise you overnight riches; it demands work and application to perform it. After finishing the Super Affiliate System online video training course, attaining success requires you to put John’s strategies into practice. A lot of commitment, hard work, and time are required in order to become a successful affiliate marketer.

How Does It Work?

As its name suggests, the Super Affiliate System is there to make you a super affiliate. John himself is an experienced affiliate, and he has accumulated all the necessary tools to achieve success in training others to become super affiliates. The Super Affiliate Network System members’ area has outlined everything that the veteran affiliate used to make millions as an affiliate.
The guide will help you set up campaigns, traffic resources, essential tools you need as an affiliate, and the veteran affiliate networks to achieve success.

Most amateur affiliates usually get frustrated as they might demand time to start making money. Those who succeed in getting little coins mainly do the following to earn;

They first become Super Affiliate System affiliates.

They promote the Super Affiliate System in multiple ways.

They convert the marketing leads they get into sales.

They receive a commission on every sale they make.

Affiliate marketing involves trading other people’s products and earning commissions from the sales you make. It’s an online business that can be done either with free or paid traffic. With the Super Affiliate System, one of the basic teachings you’ll get in the guide is how to make money by promoting the course itself using paid traffic Facebook ads.

What’s in the Super Affiliate System?

The system is amongst the most comprehensive affiliate marketing courses on the market. The Super Affiliate System comprises more than 50 hours of content that takes about six weeks to complete. The Super Affiliate System also includes several video lectures and tutorials alongside several questions and homework assignments to test its retention.

What Does the Super Affiliate Program Cover?

This program aims to provide affiliates with comprehensive ideas and tactics to become successful affiliate marketers. Therefore, their online video training course is comprehensive. Below are areas of information included within the modules;

Facebook ads

Native ads

Website creation

Google ads

Social ads

Niche selection

YouTube ads

Content creation

Scaling

Tracking and testing

Affiliate networks

Click funnels

Advanced strategies

Besides the extensive information the creator has presented on these topics, he also went an extra mile to review the complete material and also guide marketers through the course.

Who is the Super Affiliate System for?

There are a number of digital products out there that provide solutions to techniques to earn money online. But not all options offer real value for what you want. John gives people a Super Affiliate System free webinar to allow them to learn what the system entails. It will help if you spare time to watch it, as it takes 90 minutes to get through. 
Below is a brief guide to who this system is for:

  1. It is for beginners who can equip themselves with appropriate affiliate marketing skills. People who are still employed and want to have an alternative earning scheme fit here.

  2. The system is also suitable for entrepreneurs who need to learn to earn money online, mainly using paid ads.

  3. The Super Affiliate System also suits anyone who is looking for another alternative stream of income.

Making money online has many advantages at large. You have the flexibility to work from any place, in the comfort of your home, with just an internet connection. Even though John has stated that there are no special skills needed to achieve success in affiliate marketing, there are little basics necessary to keep you on track. 
Having a proper mindset is also vital to attaining success in affiliate marketing. So, affiliates who believe in the system working for them need to be dedicated, focused, and committed. 
They incorporate;

Keep in mind that you have more than $895 in advertisements to get started. Furthermore, set aside a couple of dollars so that you keep on the right track.
There is also additional software you require to get started. It needs an extra of between $80 and $100 a month to get it.

Where to Buy a Super Affiliate System?

If you are interested in joining this big team, you have to get into the Super Affiliate System on the official website, superaffiliatesystem.org, and get it from there. You have to pay their set fees to get their courses and other new materials within their learning scope.

Super Affiliate System Review: Is it Worth the Money?

It depends on an individual whether the system is worth it or not. The system is worth the money for serious people who want to go deep into an affiliate marketing career and have the time to put the Super Affiliate System strategies into practice. Super Affiliate System Review, Is it worth your money?
But people who also look forward to becoming rich overnight need to get off as this is not your way. Hard work and commitment are paramount to getting everything that works best for you.

**Visit The Officail Website

#super affiliate system review #super affiliate system #super affiliate system 3 #super affiliate system 3.0 review #super affiliate system pro #super affiliate system john crestani

Joseph  Murray

Joseph Murray

1623967440

Reference Variable in Java

Before We Started with the Reference variable we should know about the following facts.

**1. **When we create an object(instance) of class then space is reserved in heap memory. Let’s understand with the help of an example.

Demo D1 = new Demo();

Reference Variable

Now, The space in the heap Memory is created but the question is how to access that space?.

Then, We create a Pointing element or simply called Reference variable which simply points out the Object(the created space in a Heap Memory).

Heap Memory

**Understanding Reference variable **

1. Reference variable is used to point object/values.

**2. **Classes, interfaces, arrays, enumerations, and, annotations are reference types in Java. Reference variables hold the objects/values of reference types in Java.

3. Reference variable can also store null value. By default, if no object is passed to a reference variable then it will store a null value.

**4. **You can access object members using a reference variable using **dot **syntax.

.<instance variable_name / method_name>

#java #reference variable in java #variables in java #reference variables #refer #variable's