Virtual threads can be one of the easiest throughput wins in a blocking Spring Boot application. The switch is one line: spring: threads: virtual: enabled: true But that line changes the concurrency model of the application. It does not make database queries faster, reduce API latency, or create more database connections. It makes waiting cheaper by allowing many request tasks to share a smaller number of carrier threads. ...
JAVA Streams Sum of Elements Given a list of integers, compute the sum of all numbers. // using sum List<Integer> arr = Arrays.asList(1, 4, 5, 6, 22, 3, 90, 89, 2, 1, 3, 4, 55, 6); int sum = arr.stream() .mapToInt(Integer::intValue) .sum(); // or int sum3 = arr.stream() .reduce((a,b) -> a + b) .get(); // or int sum2 = arr.stream() .reduce(0, (total, n) -> total + n, (total1, total2) -> total1 + total2); Average of Elements Given a list of integers, compute the average of all numbers. ...
Thread Thread Subclass Here is an example of creating a Java Thread subclass: public class MyThread extends Thread { public void run(){ System.out.println("MyThread running"); } } To create and start the above thread you can do like this: MyThread myThread = new MyThread(); myTread.start(); You can also create an anonymous subclass of Thread like this: Thread thread = new Thread(){ public void run(){ System.out.println("Thread Running"); } } thread.start(); Runnable Interface Implementation Java Class Implements Runnable public class MyRunnable implements Runnable { public void run(){ System.out.println("MyRunnable running"); } } Anonymous Implementation of Runnable Runnable myRunnable = new Runnable(){ public void run(){ System.out.println("Runnable running"); } } Java Lambda Implementation of Runnable Runnable runnable = () -> { System.out.println("Lambda Runnable running"); }; Starting a Thread With a Runnable Runnable runnable = new MyRunnable(); // or an anonymous class, or lambda... Thread thread = new Thread(runnable); thread.start(); The Java Memory Model Here is a diagram illustrating the call stack and local variables stored on the thread stacks, and objects stored on the heap: ...
Core Java Core Java String Concepts HashCode & Equal Methods Immutability OOPS Concepts Abstraction Encapsulation Polymorphism Inheritance String Concepts A String is a sequence of characters. How to create a String object? String literal String s1="Welcome"; String s2="Welcome";//It doesn't create a new instance New keyword String s=new String("Welcome"); //creates object and reference variable Examples:- String s1 = "Hello"; char ch[] = {'H', 'e', 'l', 'l', 'o'}; String s2 = new String(ch); String s3 = "Hello"; String s4 = new String("Hello"); String s5 = new String("Hello"); System.out.println(s1 == s2); // false System.out.println(s1 == s3); // true System.out.println(s4 == s5); // false HashCode & Equal Methods Default implementations of equals() and hashcode() methods: ...