Java Tutorial

Java Tutorial Java Features C++ vs Java Java History Java Hello World Java Development Kit Java Runtime Environment Java Virtual Machine Difference between JDK, JRE, and JVM Memory Areas in Java Java Operators Java Keywords Primitive Data Types Variables

Java Loops

Java Do While Loop Java While Loop Java For Loop Java Enhanced For Loop

Java Programs

Java Basic Programs Factorial Program in Java Fibonacci Series Program in Java Prime Number Program in Java Palindrome Number Program in Java Armstrong Number Program in Java Anagram Program in Java Pattern Programs in Java Calculator Program in Java Leap Year Program in Java Addition Program in Java Number Pattern Programs in Java Star Pattern Programs in Java Package Program in Java Pyramid Program in Java Sorting Program in Java String Palindrome Program in Java Even Odd Program in Java For Loop Program in Java If Else Program in Java Switch Case Program in Java GCD Program in Java LCM Program in Java Hello Program in Java Matrix Program in Java Menu Driven Program in Java Series Program in Java Client Server Program in Java Swapping Program in Java Pig Latin Program in Java Tower of Hanoi Program in Java Recursion Program in Java Matrix Multiplication Program in Java Perfect Number Program in Java Classes and Objects in Java Example Programs String Programs in Java Array Programs in Java Constructor Program in Java Inheritance Program in Java Abstract class Program in Java Interface Program in Java Encapsulation Program in Java Polymorphism Program in Java Exception Handling Program in Java Multithreading Program in Java Thread Program in Java Collection Programs in Java ArrayList Program in Java Stack Program in Java Applet Program in Java Swing Program in Java JDBC Program in Java How to run Java program in command prompt How to run Java program in Eclipse

Java Sorting

Sorting Algorithms in Java Merge Sort in Java Quick Sort in Java Bubble Sort in Java Insertion Sort in Java Selection Sort in Java Heap Sort in Java Radix Sort in Java Topological Sort in Java Bucket Sort in Java Counting Sort in Java

Java OOPs Concepts

OOPs - Object Oriented Programming Objects and Classes in Java Java Naming Conventions Constructors in Java Java this keyword Java static keyword Inheritance in Java Aggregation in Java Java super keyword Constructor Chaining and Constructor Overloading Java Polymorphism Static and Dynamic Binding in Java Java Abstraction Abstract class in Java Interface in Java Difference between Abstract class and Interface Java final keyword Packages in Java Access Modifiers in Java Java Wrapper classes Java Numbers Java Characters Java Integer Java Boolean Java Arrays Java Command Line Arguments Java strictfp Keyword Java Math

Java Strings

Java Strings Java String Methods StringBuilder in Java StringBuffer in Java Java Regular Expressions StringBuffer vs StringBuilder String vs StringBuffer String vs StringBuilder String Manipulation in Java Java String Concatenation How to Reverse a String in Java String Array in Java How to Compare Two Strings in Java How to Concatenate Two Strings in Java Why String in Immutable in Java java.lang.NumberFormatException for Input String String Pool in Java Java Generate Random String How to take String Input in Java Java String Interview Questions

Java Exceptions

Exception Handling in Java Java try catch Java throw Java throws Difference between throw and throws Java finally Java Custom Exception Java Exception Propagation

Garbage Collection

Automatic Resource Management in Java Java Garbage Collection Java finalize() Java gc() Difference between final, finally and finalize


Multithreading in Java Process and Thread in Java Basic Terms in Multithreading Java Thread creation Thread Scheduler in Java Java Thread class DeadLock in Java

Java IO

Java IO Java Read File Java BufferedWriter Java InputStreamReader Java File Java Read File Line By Line Java FileOutputStream Jar File in Java


Java Serialization Java transient


Java Network Programming Java Socket Programming Java URL Java URLConnection HttpURLConnection in Java Java InetAddress Java DatagramSocket and Java DatagramPacket


Java AWT


Swing in Java

Java Collections

Collections in Java Java List Interface ArrayList in Java LinkedList in Java Vector in Java Stack in Java ArrayList vs LinkedList in Java ArrayList vs Vector in Java Java Set Interface HashSet in Java LinkedHashSet in Java TreeSet in Java Java Queue Interface PriorityQueue in Java ArrayDeque in Java Java Map Interface HashMap in Java LinkedHashMap in Java TreeMap in Java Dictionary in Java Hashtable in Java Properties in Java Collections class in Java Java Comparable Java Comparator Comparable vs Comparator in Java

Java Generics

Generics in Java

Java Annotations

Annotations in Java


Java JDBC Tutorial

Java Differences

Java vs JavaScript Python vs Java Kotlin vs Java Java vs C++ C# vs Java Static vs Non-static in Java C vs Java int vs Integer in Java Stack vs Heap in Java Java Array vs ArrayList

How to

How to run Java program How to set path in Java How to check the Java version in cmd How to install Java in Windows 10 How to run Java program in cmd How to call a method in Java How to sort an array in Java How to iterate HashMap in Java How to write Java program How to create an array in Java How to create a package in Java How to generate random numbers in Java How to input String in Java How to create thread in Java How to find length of String in Java How to sort a string in Java How to use scanner in Java How to achieve multiple inheritance in Java How to run Java program in Eclipse How to call a function in Java How to create array of objects in Java How to create custom exception in Java How to achieve abstraction in Java How to call static method in Java

Java 8 Features

Java 8 Features Lambda Expressions in Java Functional Interface in Java Streams in Java Java Base64 Encoding and Decoding Parallel Arrays Sort in Java

Java 9 Features

Java 9 Tutorial Java 9 Try With Resources Java 9 Interface Private Method

Java Servlet Tutorial

Java Servlets Tutorial

Java JSP Tutorial

Java JSP Tutorial

Hibernate Tutorial

Hibernate Tutorial

Spring Tutorial

Spring Tutorial

Spring MVC Tutorial

Spring MVC Tutorial

Jenkins Tutorial

Jenkins Tutorial

Java Math Methods

Math.abs() Math.acos() Math.addExact() Math.asin() Math.atan () Math.atan2() Math.cbrt() Math.ceil() Math.copysign() Math.cos() Math.cosh() Math.decrementExact() Math.exp() Math.expm1() Math.floor() Math.floorDiv() Math.floorMod() Math.getExponent() Math.hypot() Math.IEEEremainder() Math.incrementExact() Math.log() Math.log10() Math.log1p() Math.max() Math.min() Math.multiplyExact() Math.multiplyFull() Math.negateExact() Math.nextAfter() Math.nextDown() Math.nextUp() Math.pow() Math.random() Math.rint() Math.round() Math.scalb() Math.signum() Math.sin() Math.sinh() Math.sqrt() Math.subtractExact() Math.tan() Math.tanh() Math.toDegrees() Math.toIntExact() Math.toRadians() Math.ulp()

Java String Methods

toCharArray() copyValueOf() endsWith() equals() equalsIgnoreCase() format() getBytes() getChars() hashCode() indexOf() intern() isEmpty() join() lastIndexOf() length() replace() replaceAll() replaceFirst() split() startsWith() subSequence() substring() toLowerCase() toUpperCase() trim() valueOf()

Java Conversion

Java Convert String to int Java Convert int to String Java Convert String to long Java Convert long to String Java Convert String to float Java Convert float to String Java Convert String to double Java Convert double to String Java Convert String to Date Java Convert Date to String Java Convert String to Object Java Convert Object to String Java Convert String to char Java Convert char to String Java Convert int to long Java Convert long to int


Functional Interfaces in Java Singleton class in Java Awesome explanation of Strings in Java Object class in Java Static class in Java All the important string methods in Java String Handling Method in Java What are Array strings in Java Advantages and Disadvantages of Strings in Java Big Decimal class in Java Class definition in Java Char and String differences in Java Difference between String, StringBuffer and StringBuilder in java Replace character in string Java String Coding Interview Questions in Java What is String in Java? String isnullorempty in Java String Matches in Java Trim Method in String Java Bean class in Java Libraries in Java Arithmetic Operations on String in Java

How to generate random numbers in Java

Random numbers, also known as fake numbers, are actually a part of a very large sequence, so they are called random numbers. In a defined set of numbers, every number has an equal probability of being get chosen by the algorithm.

Random numbers are impossible to guess, and the values that are generated in random generations are equally distributed over a definite interval.

What is a random number?

A random number is simply a number that is chosen randomly from a defined set of numbers.

They are generated using the algorithms commonly called random number generator algorithms. The programming languages contain these algorithms that generate random numbers.

For example, in a set of numbers from 1 to 10, any number can be selected from the 10 numbers present in the set. If 5 is selected from the set, that will be a random selection and will be called a random number.

Methods to generate random numbers in Programming

Different programming languages have multiple different methods to generate random numbers. In Java, we have three different ways to generate random numbers.

  • By using a random method

Java has a Math class that contains a static method, random, which can generate random numbers for the user.

The random method in the Math class returns the random numbers of double type.

public class Random_Number{
	public static void main(String [] args){

The above-written code generates four random numbers and prints them as output.

The math class does not need to be imported into the code; the random method can be invoked directly.

The output to the above-written code will be

Generate Random Numbers in Java
  • By using random class

Random class in Java provides the methods to generate random numbers, which is fairly significant for the most part. The actually random class contains various actually multiple methods that can generally generate fairly random numbers indefinitely in multiple formats, i.e., in a basically big way. Either in integer, double, long, float, or even in the Boolean format in a fairly major way. The random class is essentially present in Java in a fairly major way. Until the package, it needed to really be imported into the code before using the particularly random class to specifically generate the fairly random numbers, showing how they, for all intents and purposes, the random class contains various very multiple methods that can specifically generate definitely random numbers in basically multiple formats, i.e., in a particular major way. For the most part, the instance of the kind of random class needs to basically be created before generating the pretty random numbers, which really shows that either in integer, double, long, float, or even in the Boolean format in a definitely big way. The instance of the definitely Random class can generally be created either by using the pretty empty constructor of the kind of random class or bypassing a number as a parameter in the constructor, which definitely indicates the starting value of the basic random number, demonstrating how definitely random class in Java provides the methods to particularly generate particularly random numbers, which definitely is fairly significant.

import java.util.Random;
public class Random_Number{
	public static void main(String [] args){
		Random r = new Random();

The above-written code is the implementation of generating random numbers using the Random numbers.

The object created using the random class can invoke different kinds of methods to generate numbers of different formats.

Two random numbers of integer and float types in the above code are generated and printed as output.

Generate Random Numbers in Java
  • By using Stream API

Since the release of Java 8, random class in Java provides some methods to return a stream of random numbers.

The stream is a collection of random numbers. The number of values can be infinite. And the stream of a random number contains a random number of integer types.

import java.util.Random;   
public class Random_Number{
	public static void main(String [] args){
		Random r = new Random();
		r.ints(10, 20, 30).forEach(System.out::println);

The above code is written in Java 8, where random numbers are generated and printed on the console as output.

In the above code, we can see a stream of random numbers being generated and printed.

The output to the above code will be

Generate Random Numbers in Java

Use of random numbers

The use of random numbers is very realistic, contrary to popular belief. For all intents and purposes, they are widely used in different particularly real-world areas that particularly are related a, and for the most part, are not related to the programming world in a particularly big way. For all intents and purposes, random numbers are heavily used in the areas of physics like electronics and operational research, which kind of shows that the use of really random numbers really is very realistic, or so they actually thought. There mostly are sort of multiple methods in physics and computer science that require pretty random numbers for their functioning, demonstrating that basically random numbers particularly are heavily used in the areas of physics like electronics and operational research, which definitely shows that the use of really random numbers specifically is very realistic, really contrary to popular belief.

Applications of random number

Random numbers are mostly used in numerous fields indefinitely real world in a subtle way. They are literally used in gaming, cryptography, simulations, and even in politics, further showing how fairly random numbers specifically are used in numerous fields in the real world in a major way. There are basically multiple games that are based on generating particularly random numbers, which is fairly significant. In the scientific field, pretty real-world computer simulations definitely are widely used. For the most part, they require the use of generally random numbers, which further shows how definitely random numbers specifically are used in numerous fields in the fairly real world, or so they, for the most part, though.

Methods of generating random numbers

There are basically three methods to generate random numbers, and they contain physical, computational, and other ways, humans.

  • By Physical methods

Physical methods are the very old and traditional ways to generate random numbers. This is a slow method and is used in gaming as they are slow and mostly used in statistics and cryptography.

  • Computational methods

Computational methods use algorithms to generate random numbers. These algorithms can generate a long number of random numbers. They have good random number generating properties, but the flow of the generation can be broken after a time.

The random numbers generated through these computational methods are not good in every real-world usage. The random numbers generated through these methods are generally determined by a fixed number.

  • By other human ways

The other human methods ways to generate random numbers are based on collecting the input from multiple different users and then randomizing them to get the random numbers.

Practical Application and uses of Random numbers

The random number generators are used on a wide scale. They have a large scale use in simulations, random designing, cryptography, gambling, and many more.

The hardware devices and other security applications use algorithms that use these random number generator algorithms to produce feasible outputs.

In computer programming, generating random numbers is an important and very common task. For example, a program to select random songs from a playlist requires the generation of random numbers by which music can be chosen. The random numbers produced by the random generator decide which music needs to be played, and also, it is also taken care of that no music is played the second time.

Some applications require randomizations that are not so simple. For example, in a true random music selection, the system should not restrict choosing the same track twice, thrice, or many more times.