Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Articles on Trending Technologies
Technical articles with clear explanations and examples
Methods Accepting a Variable Number of objects in Java
A method that accepts a variable number of Object arguments in Java is a form of variable length arguments(Varargs). These can have zero or multiple Object type arguments.A program that demonstrates this is given as follows:Examplepublic class Demo { public static void Varargs(Object... args) { System.out.println("Number of Object arguments are: " + args.length); System.out.println("The Object argument values are: "); for (Object i : args) System.out.println(i); } public static void main(String args[]) { Varargs("Apples", "4", "All"); Varargs("Half of", 3, "is", ...
Read MoreLongStream rangeClosed() method in Java
The rangeClosed() method of the LongStream class in Java returns a sequential ordered LongStream from startInclusive to endExclusive by an incremental step of 1. This is inclusive of the initial element and the last element.The syntax is as follows −static LongStream rangeClosed(long startInclusive, long endExclusive)Here, startInclusive is the first value, whereas the endExclusive is the last.To use the LongStream class in Java, import the following package −import java.util.stream.LongStream;The following is an example to implement LongStream rangeClosed() method in Java −Exampleimport java.util.stream.LongStream; public class Demo { public static void main(String[] args) { ...
Read MoreCan we declare final variables without initialization in java?
In Java, final is the access modifier which can be used with a filed class and a method.When a method if final it cannot be overridden.When a variable is final its value cannot be modified further.When a class is final it cannot be extended.Declaring final variable without initializationIf you declare a final variable later on you cannot modify or, assign values to it. Moreover, like instance variables, final variables will not be initialized with default values.Therefore, it is mandatory to initialize final variables once you declare them.Still, if you try to declare final variables without initialization that will generate a ...
Read MoreSet vs HashSet vs TreeSet in Java
A Set is a generic set of values with no duplicate elements. A TreeSet is a set where the elements are sorted.A HashSet is a set where the elements are not sorted or ordered. It is faster than a TreeSet. The HashSet is an implementation of a Set.Set is a parent interface of all set classes like TreeSet, HashSet, etc.Exampleimport java.util.*; public class Demo { public static void main(String args[]) { int a[] = {77, 23, 4, 66, 99, 112, 45, 56, 39, 89}; Set s = new HashSet(); try ...
Read MoreGet first entry from NavigableMap in Java
To display first entry from NavigableMap in Java, use the firstEntry() method.Let us first create NavigableMap −NavigableMap n = new TreeMap(); n.put("A", 498); n.put("B", 389); n.put("C", 868); n.put("D", 988); n.put("E", 686); n.put("F", 888); n.put("G", 999); n.put("H", 444); n.put("I", 555); n.put("J", 666);Get the first entry now −n.firstEntry()The following is an example to get first entry from NavigableMap.Exampleimport java.util.*; public class Demo { public static void main(String[] args) { NavigableMap n = new TreeMap(); n.put("A", 498); n.put("B", 389); ...
Read MoreHow many ways are there to initialize a final variable in java?
In Java, final is the access modifier which can be used with a filed, class and a method.When a method if final it cannot be overridden.When a variable is final its value cannot be modified further.When a class is final it cannot be extended.Initializing a final variableOnce you declare a final variable, it is a must to initialize it. You can initialize the final instance variable −At the time of declaration as.public final String name = "Raju"; public final int age = 20;Within an instance (non-static) block.{ this.name = "Raju"; this.age = 20; }Within a default constructor.public final ...
Read MoreCheck two HashMap for equality in Java
To check whether two HashMap are equal or not, use the equals() method.Let us first create the first HashMap −// Create hash map 1 HashMap hm1 = new HashMap(); hm1.put("Shirts", new Integer(700)); hm1.put("Trousers", new Integer(600)); hm1.put("Jeans", new Integer(1200)); hm1.put("Android TV", new Integer(450)); hm1.put("Air Purifiers", new Integer(300)); hm1.put("Food Processors", new Integer(950));Let us now create the second HashMap −HashMap hm2 = new HashMap(); hm2.put("Shirts", new Integer(700)); hm2.put("Trousers", new Integer(600)); hm2.put("Jeans", new Integer(1200)); hm2.put("Android TV", new Integer(450)); hm2.put("Air Purifiers", new Integer(300)); hm2.put("Food Processors", new Integer(950));To check whether both the HashMap are equal or not, use the equals() method like this −hm1.equals(hm2)The following is ...
Read MoreHow to extend Interfaces in Java
An interface contains variables and methods like a class but the methods in an interface are abstract by default unlike a class. An interface extends another interface like a class implements an interface in interface inheritance.A program that demonstrates extending interfaces in Java is given as follows:Exampleinterface A { void funcA(); } interface B extends A { void funcB(); } class C implements B { public void funcA() { System.out.println("This is funcA"); } public void funcB() { System.out.println("This is funcB"); } } public class Demo { public ...
Read MoreByteBuffer asShortBuffer() method in Java
A view of the ByteBuffer can be created as a ShortBuffer using the asShortBuffer() method in the class java.nio.ByteBuffer. This method requires no parameters and it returns a short buffer as required. This buffer reflects the changes made to the original buffer and vice versa.A program that demonstrates this is given as follows −Exampleimport java.nio.*; import java.util.*; public class Demo { public static void main(String[] args) { int n = 50; try { ByteBuffer bufferB = ByteBuffer.allocate(n); ShortBuffer bufferS = bufferB.asShortBuffer(); ...
Read MoreThe addIfAbsent() method of CopyOnWriteArrayList in Java
The addIfAbsent() method appends the element if it is not in the list. If the element is already in the list, then FALSE is returned.The syntax is as follows.public boolean addIfAbsent(E ele)Here, ele is the element to be added to this list, if it is not already in the list.To work with CopyOnWriteArrayList class, you need to import the following package.import java.util.concurrent.CopyOnWriteArrayList;The following is an example to implement CopyOnWriteArrayList class addIfAbsent() method in Java.Exampleimport java.util.concurrent.CopyOnWriteArrayList; public class Demo { public static void main(String[] args) { CopyOnWriteArrayList arrList = new CopyOnWriteArrayList(); arrList.add(30); arrList.add(40); arrList.add(60); ...
Read More