Programming Articles - Page 2775 of 3366

The subList() method returns a part of this list between the specified fromIndex, inclusive, and toIndex, exclusive. Get a sublist using the method by setting the range as the two parameters.The syntax is as follows.public List subList(int fromIndex, int toIndex)Here, the parameter fromIndex is the low endpoint (inclusive) of the subList and toIndex is the high endpoint (exclusive) of the subList.To work with the AbstractList class, import the following package.import java.util.AbstractList;The following is an example to implement subList() method of the AbstractlList class in Java.Exampleimport java.util.ArrayList; import java.util.AbstractList; public class Demo {    public static void main(String[] args) {   ... Read More

The toArray() method returns an array containing the elements of this stream.Set the elements in the stream with the IntStream class of() method.IntStream stream = IntStream.of(20, 40, 60, 70, 100, 120, 140);Now, display an array with the elements of this stream using the toArray() method.int[] myArr = stream.toArray();The following is the syntax.int[] toArray()The following is an example to implement IntStream toArray() method in Java.Example Live Demoimport java.util.*; import java.util.stream.IntStream; public class Demo {    public static void main(String[] args) {       IntStream stream = IntStream.of(20, 40, 60, 70, 100, 120, 140);       int[] myArr = stream.toArray();       System.out.println(Arrays.toString(myArr));    } }Output[20, 40, 60, 70, 100, 120, 140]

The averagingInt() method of the Collectors class returns a Collector that produces the arithmetic mean of a int-valued function applied to the input elements.The syntax is as follows −static Collector averagingInt(ToIntFunction

It can be checked if the days, months and years in the Period are negative or not using the isNegative() method in the Period class in Java. This method requires no parameters. Also, it returns true if any of the days, months and years in the Period are negative and false if all of the days, months and years in the Period are positive.A program that demonstrates this is given as followsExample Live Demoimport java.time.Period; public class Demo {    public static void main(String[] args) {       String period = "P5Y9M4D";       Period p = Period.parse(period);   ... Read More

Scrapy spiderScrapy spider is a class which provides the facility to follow the links of a website and extract the information from the webpages.This is the main class from which other spiders must inherit.ScrapinghubScrapinghub is an open source application to run Scrapy spiders. Scrapinghub turns web content into some useful data or information. It allows us to extract the data from webpages, even for complex webpages.We are going to use scrapinghub to deploy scrapy spiders on cloud and execute it.Steps to deploy spiders on scrapinghub −Step1 −Create one scrapy project −After installing scrapy, just run the following command in your ... Read More

The mapToDouble() method returns a DoubleStream consisting of the results of applying the given function to the elements of this stream.The syntax is as follows.DoubleStream mapToDouble(IntToDoubleFunction mapper)Here, the parameter mapper is the stateless function applied to each element.Create an IntStream with some elements.IntStream intStream = IntStream.of(5, 20, 25, 45, 60, 75, 85, 90);Now, use the mapToDouble() method to return a DoubleStream.DoubleStream doubleStream = intStream.mapToDouble(val -> (double) val);The following is an example to implement IntStream mapToDouble() method in Java.Example Live Demoimport java.util.*; import java.util.stream.IntStream; import java.util.stream.DoubleStream; public class Demo {    public static void main(String[] args) {       IntStream intStream ... Read More

The equality of two Periods can be determined using the equals() method in the Period class in Java. This method requires a single parameter i.e. the Period object to be compared. Also it returns true if both the Period objects are equal and false otherwise.A program that demonstrates this is given as followsExample Live Demoimport java.time.Period; public class Demo {    public static void main(String[] args) {       String period1 = "P5Y7M15D";       Period p1 = Period.parse(period1);       String period2 = "P5Y7M15D";       Period p2 = Period.parse(period2);       System.out.println("The Period p1 ... Read More

The counting() method of the Java 8 Collectors class returns a Collector accepting elements of type T that counts the number of input elements.The syntax is as follows −static Collector counting()Here, the parameter −T − type of input elementsLong − This class value of the primitive type long in an objectTo work with Collectors class in Java, import the following package −import java.util.stream.Collectors;The following is an example to implement counting() method in Java 8 −Example Live Demoimport java.util.stream.Collectors; import java.util.stream.Stream; public class Demo {    public static void main(String[] args) {       Stream stream = Stream.of("25", "50", ... Read More

The peek() method of the ArrayBlockingQueue class returns the head of this queue or null if this queue is empty.The syntax is as follows.public E peek()To work with ArrayBlockingQueue class, you need to import the following package.import java.util.concurrent.ArrayBlockingQueue;The following is an example to implement peek() method of Java ArrayBlockingQueue class.Example Live Demoimport java.util.concurrent.ArrayBlockingQueue; public class Demo {    public static void main(String[] args) throws InterruptedException {       ArrayBlockingQueue q = new ArrayBlockingQueue(10);       q.add(200);       q.add(310);       q.add(400);       q.add(450);       q.add(500);       q.add(550);       ... Read More

An immutable copy of the Period object where some days are added to it can be obtained using the plusDays() method in the Period class in Java. This method requires a single parameter i.e. the number of days to be added and it returns the Period object with the added days.A program that demonstrates this is given as followsExample Live Demoimport java.time.Period; public class Demo {    public static void main(String[] args) {       String period = "P5Y7M15D";       Period p1 = Period.parse(period);       System.out.println("The Period is: " + p1);       Period p2 ... Read More