Permeneutic Sketch. JS Object CRUD States.

A Permeneutic sketch drawn in one of my web-lectures. 
Exploring the impact of operations like freeze, seal, and preventExtentions on a JS object.

Copyright ©Rajesh Patkar, All rights reserved.

Grapes a Metaphor

If I ask Chotu how much time he will take to eat ten grapes, he will typically say a few minutes.  If I ask the same question to his digestive system, then the answer maybe a few hours. The answer depends on who is answering and what eating means. For Chotu, it is chewing,  gulping, and relishing their taste. Chotu also rejects peduncles, cap stems that come with grapes.  For his digestive system, chewing would mean breaking down and converting grapes into its ingredients, and gulping would mean incorporating them in blood, and rejection means excretion of the non-essential. As I see it, eating is of two types Deep and Shallow. Usually, what we call eating is in this context, Shallow Eating, and digestion is Deep Eating. Both are essential for survival.When we intake Knowledge, we go through a similar process. The Shallow Eating part is akin to reading books, watching videos, attending seminars, among other things. The metaphorical grapes have gone inside our system.  I would label th…

All the Courses Shifted Online

It has been a testing time since COVID Pandemic. Many established Professions, Institutions, Industries, and Systems are adapting to the new reality. Education is also changing itself.
It's been almost four months that I have not conducted a lecture in a Physical Classroom. I have sifted Online wholly. I want to thank Google, especially for it's Google Meet. All my courses stalled due to COVID, and the new ones just launched are now normalized. I have occasionally been offering Video courses to a restricted audience, but now my classes are available internationally. I am happy that I can teach students from UK, USA, Canada, Dubai, Delhi, Rajkot, Bhopal,... And of course Mumbai, all together in a batch.  Although international students have been attending my courses, they had to participate in my classes physically. The flexibility of Online arrangement is liberating.
Some new facilities in Online Courses
Registration through emailPayment is possible through any form of digital mo…

Introduced Java 10 in Java Technology Course.

Enjoying REPL with Java 10.

Introduced Java10 in the ongoing Java Technology Batch. Also playing with *.jsh files.

Sample Program ( piggybank.jsh )

import static javax.swing.JOptionPane.*;import static java.lang.Integer.*;var balance = 0;var lt = 0;void statement(){ showMessageDialog(null,"Balance = " + balance +"\n"+ " Last Transaction = "+lt);}void deposit(int v){ balance = balance + v; lt = v;}void withdraw(int v){ if(balance >= v){ balance = balance - v; lt = -v; } else{ showMessageDialog(null,"Insufficient Balance"); }}statement();var sr1 = showInputDialog("Enter amount to deposit");var r1 = parseInt(sr1);deposit(r1);statement();var r2 = parseInt(showInputDialog("Enter amount to deposit"));deposit(r2);statement();withdraw(parseInt(showInputDialog("Enter amount to withdraw")));statement();

copyright ©Rajesh Patkar, All rights reserved.
Conducted a small survey on twitter regarding the inheritance related open decorator in the Kotlin language.  The comparison was between the design semantics offered via Java's final keyword and Kotlin's open keyword.

Here are the results.

In Java every class by default is inheritable until made final. In Kotlin every class by default is not inheritable until annotated with the keyword 'open'. If you were to create your own language which approach would you prefer— RajeshPatkar (@RajeshPatkar) November 14, 2017

Java Technology POCP

Constructor Overloading Permitted in Java

copyright ©Rajesh Patkar, All rights reserved.

POCP - Proof Of Concept Program

Over years, I have found that learners get great confidence in an Assertion when it is supported by a program that proves the Assertion. These Programs apart from reasonably proving the assertion also convey the tacit scope of the given Assertion. Several salient scenarios encompassing the Assertion can be represented by a set of Programs. These set of Programs become a concrete evidence and articulate in programmatic terms the context, assumptions, limitations and implications of the underlying Assertion.

I prefer to call these program POCP ( Proof Of Concept Programs ). On one hand these programs are teaching aids for the teacher, and on the other hand they are themselves teachers for those learners who can listen to the program's voice.

I have put up a GitHub Repository to share a few POCP for Java Technology course and would encourage community activity around it.

Assertion :  Child Constructor Calls Parent Constructor
POCP      :  Child Constructor Calls Parent Constructor