automatic resource management or try-with-resources is a new exception handling mechanism that was introduced in Java 7, which automatically closes the resources used within the try-catch block.ResourceA resource is an object which is required to be closed once our program finishes. For example, a file is read, database connection and so on.UsageTo use the try-with-resources statement, you simply need to declare the required resources within the parenthesis, and the created resource will be closed automatically at the end of the block. Following is the syntax of the try-with-resources statement.Syntaxtry(FileReader fr = new FileReader("file path")) {        // use the resource ... Read More

AssociationAssociation refers to the relationship between multiple objects. It refers to how objects are related to each other and how they are using each other's functionality. Composition and aggregation are two types of association.CompositionThe composition is the strong type of association. An association is said to composition if an Object owns another object and another object cannot exist without the owner object. Consider the case of Human having a heart. Here Human object contains the heart and heart cannot exist without Human.AggregationAggregation is a weak association. An association is said to be aggregation if both Objects can exist independently. For ... Read More

AssociationAssociation refers to the relationship between multiple objects. It refers to how objects are related to each other and how they are using each other's functionality. Composition and aggregation are two types of association.CompositionThe composition is the strong type of association. An association is said to composition if an Object owns another object and another object cannot exist without the owner object. Consider the case of Human having a heart. Here Human object contains the heart and heart cannot exist without Human.AggregationAggregation is a weak association. An association is said to be aggregation if both Objects can exist independently. For ... Read More

With Java 8, Arrays class has a stream() methods to generate a Stream using the passed array as its source.DescriptionThe java.util.Arrays.stream() method returns a sequential Stream with the specified array as its source. −Arrays.stream(array)DeclarationFollowing is the declaration for java.util.Arrays.stream() methodpublic static Stream stream(T[] array)Type ParameterT − This is the type of the array elements.Parameterarray − This is the source array to be used.Return ValueThis method returns a stream for the array.ExampleThe following example shows the usage of java.util.Arrays.stream() method.Live Demoimport java.util.Arrays; public class Tester {    public static void main(String args[]) {       int data[] = { 1, ... Read More

Here is the syntax for declaring an array variable −SyntaxdataType[] arrayRefVar;   // preferred way. or dataType arrayRefVar[];  // works but not preferred way.Note − The style dataType[] arrayRefVar is preferred. The style dataType arrayRefVar[] comes from the C/C++ language and was adopted in Java to accommodate C/C++ programmers.ExampleThe following code snippets are examples of this syntax −double[] myList;   // preferred way. or double myList[];   // works but not preferred way.Creating ArraysYou can create an array by using the new operator with the following syntax −SyntaxarrayRefVar = new dataType[arraySize];The above statement does two things −It creates an array ... Read More

Array in Java can be copied to another array using the following ways.Using variable assignment. This method has side effects as changes to the element of an array reflects on both the places. To prevent this side effect following are the better ways to copy the array elements.Create a new array of the same length and copy each element.Use the clone method of the array. Clone methods create a new array of the same size.Use System.arraycopy() method.  The arraycopy() can be used to copy a subset of an array.ExampleCreate a java class named Tester.Tester.javaLive Demopublic class Tester {    public ... Read More

'+' operator in java can be used to add numbers and concatenate strings. Following rules should be considered.Only numbers as operands then result will be a number.Only strings as operands then result will be a concatenated string.If both numbers and strings as operands, then numbers coming before string will be treated as numbers.If both numbers and strings as operands, then numbers coming after string will be treated as a string.Above rule can be overridden using brackets().ExampleCreate a java class named Tester.Tester.javaLive Demopublic class Tester {    public static void main(String args[]) {             //Scenario 1: ... Read More

It is an algorithm to perform factorization on given integers. Following is the program implementing the Rho Algorithm for Prime Factorization.ProgramLive Demopublic class PollardsRho {    int num = 65;    public int gcd(int a, int b) {       int gcd = 0;       for(int i = 1; i

It is an algorithm to perform factorization on given integers. Following is the program implementing the Rho Algorithm for Prime Factorization.ProgramLive Demopublic class PollardsRho {    int num = 65;    public int gcd(int a, int b) {       int gcd = 0;       for(int i = 1; i

Sieve of Eratosthenes is the ancient algorithm to find prime numbers up to a given number.Algorithm1. Generate integers from 2 to n (Given number).2. Counting from 2 mark every 2nd integer. (multiples of 2)3. Now, starting from 3 mark every third integer. (multiples of 3)4. Finally, marking from 5 mark every 5th integer.(multiples of 5)Programimport java.util.Scanner; public class SievePrimeFactors  {    public static void main(String args[]) {       Scanner sc = new Scanner(System.in);       System.out.println("Enter a number");       int num = sc.nextInt();       boolean[] bool = new boolean[num];       ... Read More