At first, let us set an ArrayList of string −ArrayList arrList = new ArrayList(); arrList.add("Bentley"); arrList.add("Audi"); arrList.add("Jaguar"); arrList.add("Cadillac");Now, use toArray() to convert to a string array −int size = arrList.size(); String res[] = arrList.toArray(new String[size]);ExampleFollowing is the program to convert an ArrayList of String to a String array in Java ... Read More

At first, set a list with string values −List myList = new ArrayList( Arrays.asList("One", "Two", "Three", "Four"));Now, use String.join() to set them as a comma separated list −String str = String.join(", ", myList);ExampleFollowing is the program to convert string into comma separated List in Java −import java.util.*; public class Demo ... Read More

At first, create a Set of string −Set setStr = new HashSet(Arrays.asList("osCommerce", "PrestaShop", "Magento", "Wordpres", "Drupal"));Now, use the toArray() method to convert to array of string −String[] arrStr = setStr.toArray(new String[0]);ExampleFollowing is the program to convert Set of String to Array of String in Java −import java.util.Arrays; import java.util.Set; import ... Read More

Let’s say the following is our ArrayList −List arrList = Arrays.asList("John", "Jacob", "Kevin", "Katie", "Nathan");Now, convert this ArrayList to LinkedList using toCollection() −List myList = arrList.stream().collect(Collectors.toCollection(LinkedList::new));ExampleFollowing is the program to convert ArrayList to LinkedList in Java −import java.util.*; import java.util.stream.*; public class Demo {    public static void main(String args[]) ... Read More

Let’s say the following is our vector with values −Vector v = new Vector(); v.add("20"); v.add("40"); v.add("60"); v.add("80"); v.add("100");Now, convert the above Vector to List −ListmyList = new ArrayList(v);ExampleFollowing is the program to convert a Vector to List in Java −import java.util.*; public class Demo {    public static void ... Read More

Let’s say the following is our Set −Set set = new HashSet(Arrays.asList(15, 40, 60, 90, 120, 150, 200));Now, create a method to convert the above set to stream.StreamstreamOfInteger = convertSet(set);The method −private static Stream convertSet(Set set) {    return set.stream(); }ExampleFollowing is the program to convert a Set to ... Read More

At first, create a Map and set values −Map map = new HashMap(); map.put(1, "Kevin"); map.put(2, "Ryan"); map.put(3, "Nathan"); map.put(4, "Ricky"); map.put(5, "Shane"); map.put(6, "Adam");Now, convert the Map to Stream −Stream stream = map.entrySet().stream(); System.out.println("Stream (Map to Stream) = "+ Arrays.toString(stream.toArray()));ExampleFollowing is the program to convert a Map to a ... Read More

The introduction of Java 7 enhanced the switch case i.e. it support string as well.At first, set a string −String department = "AKD05";Now, use the same string in switch as shown below −switch(department)ExampleNow, check for every string using case as we normally do while using SWITCH CASE. Following is an ... Read More

The distinct() method of the stream class returns a stream consisting of the distinct elements of this stream. The syntax is as following −Stream distinct()ExampleFollowing is an example to implement the distinct() method in the Stream class −import java.util.*; public class Demo {    public static void main(String[] args) { ... Read More

The concat() method of the Stream class in Java creates a lazily concatenated stream whose elements are all the elements of the first stream followed by all the elements of the second stream. The syntax is as follows −concat(Stream