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Gopi Gorantala

I'm Gopi — 15+ years in Java, building Kafka and Flink platforms for banks, where one lost event is a financial discrepancy. I write javahandbook.com because the guides I needed didn't exist. Everything here is tested against a real cluster first.

A Complete Guide To JavaScript LocalStorage

localStorage is a property of the window object in JavaScript that allows you to store key/value pairs in a web browser. The data stored in localStorage persist even after the browser is closed, making it a useful tool for saving user data on the client side.

A Complete Guide To JavaScript LocalStorage

Is Java "pass-by-reference" or "pass-by-value"?

Java uses pass-by-value for all parameters, including both primitive data types and objects, which affects how methods behave and how they should be written.

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How to reverse the letters in a string in Java

In this article, we'll learn various ways to reverse strings in Java. An algorithmic approach with a flow chart and steps. Using java API methods to solve this problem and rotate kth elements or characters in an array.

Reverse String
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Bitwise OR, Computations, and Examples

A Bitwise OR is a binary operator that takes two-bit patterns of equal length and performs the logical inclusive OR operation on each corresponding bits pair. The result in each position is 0 if both bits are 0. Otherwise, the result is 1.

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Number Of Flips Required To Make a|b Equal to c

We need to write a program with minimum flips to make the two bits’ OR operation equal a number. If you understand the OR operations clearly, this problem will be a good challenge for your skills.

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Introduction to NOT Operator

The Bitwise NOT operator evaluates the binary representation of the value of a single input. If the bit contains 1, the output will be 0 for that bit location. If the bit contains 0, the output will be 1.

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Bitwise NOT, Computations, and Examples

Bitwise NOT, takes the input number, considers its binary representation, and inverts every bit, which means the 0 bit becomes 1, and the 1 bit becomes 0.

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Introduction to OR Operator

OR operator compares each bit of the first operand to the second operand’s corresponding bit. If both bits are 0, the corresponding result bit is set to 0. Otherwise, the corresponding result bit is set to 1

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Challenge 3: Power of 2

We solve by making use of the & operator in computers. There are many ways to solve this, of which two approaches are simple, and one is a more complex but better solution.

Twitter Registration: Single Responsibility Principle

We design Twitter registration software with the help of the single responsibility principle that contains a notification service, database repository, account service, and execution class.