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Concurrency and parallelism in Java

 Concurrency and parallelism are two concepts in programming that deal with executing multiple tasks, but they differ in their approaches and purposes. Here’s a breakdown of each: Concurrency Concurrency is about dealing with multiple tasks at once but not necessarily executing them simultaneously. It allows a system to manage multiple tasks by interleaving their execution, giving the illusion that they are running in parallel. Key Characteristics: Task Interleaving: Multiple tasks make progress by being interleaved. Context Switching: The system switches between tasks frequently. Non-deterministic: The order of execution can vary. Resource Sharing: Tasks share resources like CPU, memory, etc.      In this example, thread1 and thread2 run concurrently, and the output will interleave the print statements from both threads. public class ConcurrencyExample {     public static void main(String[] args) {         Thread thread1 = n...

Getting Started with the Java Flow API

Exploring the Java Flow API The Java Flow API, introduced in Java 9, provides a standard and efficient way for components of a reactive system to communicate with each other asynchronously, without requiring them to know each other's implementation details. In this post, we'll explore the key components of the Flow API and show how to use them to implement the Observer pattern in a more standardized way. Key Components of the Flow API The Flow API defines four key components: Publisher , Subscriber , Subscription , and Processor . Publisher A Publisher is a provider of data items, which publishes them to one or more Subscriber instances. To implement a custom Publisher, you need to implement the java.util.concurrent.Flow.Publisher interface, which defines the following methods: subscribe(Subscriber<? super T> subscriber) : Subscribes a Subscriber to this Publisher , returning a new Subscription instance that represents the connection between them. S...

Introduction to Lambdas in Java

Lambdas are a powerful addition to the Java language, introduced in Java 8, that allow developers to write more concise and readable code by representing functionality as a method argument or code block. In this post, we'll provide a complete introduction to lambdas in Java, including what they are, how they work, and some common use cases. What are Lambdas? In Java, a lambda expression is a short block of code that represents a method implementation. Lambdas provide a concise way to write code that can be passed around as a method argument or stored in a variable. Lambdas are often used in functional programming to represent behavior as data. Here's an example of a lambda expression in Java: Function<Integer, Integer> square = x -> x * x; This code defines a lambda expression that takes an integer as input, squares it, and returns the result. The lambda is assigned to a variable of type Function<Integer, Integer> , which represents a function that takes an ...

Streams in Java

Streams are a powerful addition to the Java language, introduced in Java 8, that allow developers to easily process collections of data in a functional, declarative manner. In this post, we'll provide a complete introduction to Java streams, including what they are, how they work, and some common use cases. What are Java Streams? In Java, a stream is a sequence of elements that can be processed in parallel or sequentially. Streams are a high-level abstraction that allow developers to easily apply functional transformations to collections of data, without having to worry about the underlying implementation details. Streams are different from traditional Java collections in several ways. Unlike collections, streams don't store data, and they don't have a specific order or size. Instead, streams provide a pipeline of operations that can be applied to a source of data, such as a list or array. Streams can be created from a variety of sources, including collections, arrays, ...

Loop in Java

A loop is a programming structure that allows a block of code to be executed repeatedly. This is useful for tasks that need to be performed multiple times, such as iterating through a list of items or printing a table of numbers. There are three main types of loops in Java: for loops, while loops, and do-while loops. For loops iterate over a fixed range of values. For example, the following for loop will iterate over the numbers from 1 to 10: for (int i = 1; i While loops continue to execute as long as a condition is true. For example, the following while loop will iterate as long as the variable `i` is less than 10: int i = 1; while (i Do-while loops are similar to while loops, but the condition is checked at the end of the loop instead of at the beginning. int i = 1; do { System.out.println(i); i++; } while (i How to Use a Loop in Java To use a loop in Java, you first need to create a variable to store the value tha...

Loops in Java 8

Java 8 introduces a number of new features for loops, including the forEach() method and the Stream API. The forEach() method is a great way to iterate over a collection without having to worry about keeping track of the index. It is also more efficient than using a for loop. The Stream API is a new way of working with collections, and it provides a number of new features and benefits. One of the benefits of the Stream API is that it can be used to perform parallel processing. These are just a few of the new features of Java 8 loops. If you are using Java 8, I encourage you to explore the new features and see how they can be used to improve your code. Here is an example of how to use the forEach() method to print out all of the elements in a List: List list = Arrays.asList("Hello", "World"); list.forEach(System.out::println); Here is an example of how to use the Stream API to perform parallel processing: List list = Arrays....

switch case in java

The switch statement in Java is a control flow statement that allows you to test a variable or an expression against multiple cases. It's similar to the if-else statement, but it can be a more convenient and efficient way to handle multiple conditions. The basic structure of a switch statement is as follows:  The expression is the variable or expression that you want to test. The case statement is followed by a value or an expression, and the code that follows the case statement will be executed if the expression matches that value. The break statement is used to exit the switch statement and prevent the execution of the next case.   Here's an example of a switch statement in Java:  In Java 8, the switch statement was enhanced to support lambda expression as well. It allows you to use a functional interface inside the case statement, which makes the switch statement more powerful. Here's an example of how you can use a lambda expression in a switch statement...