To remove all the elements from LinkedHashSet in Java, use the clear() method.The following is an example to declare LinkedHashSet and add elements to it −LinkedHashSet hashSet = new LinkedHashSet(); hashSet.add(10); hashSet.add(20); hashSet.add(30); hashSet.add(40); hashSet.add(50); hashSet.add(60);Use the clear() method to remove all elements −hashSet.clear();The following is an example −Example Live Demoimport ... Read More

To display the last entry from NavigableMap in Java, use the lastEntry() 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 last entry now.n.lastEntry()The following is an example to ... Read More

Use the containsKey() method to check whether a particular key exists in LinkedHashMap or not.Create a LinkedHashMap −LinkedHashMap l = new LinkedHashMap(); l.put(1, "Mars"); l.put(2, "Earth"); l.put(3, "Jupiter"); l.put(4, "Saturn"); l.put(5, "Venus");Now, let’s say we need to check whether key 4 exists or not. For that, use the containsKey() method ... Read More

Elements can be filled in a Java double array in a specified range using the java.util.Arrays.fill() method. This method assigns the required double value in the specified range to the double array in Java.The parameters required for the Arrays.fill() method are the array name, the index of the first element ... Read More

The headset() method returns elements up to a limit defined as a parameter.First, create a NavigableSet and add elements −NavigableSet set = new TreeSet(); set.add(10); set.add(25); set.add(40); set.add(55); set.add(70); set.add(85); set.add(100);Now, use the headset() method −set.headSet(55));The following is an example −Example Live Demoimport java.util.NavigableSet; import java.util.TreeSet; public class Demo {   ... Read More

First, create a LinkedHashSet and add elements −LinkedHashSet l = new LinkedHashSet(); l.add(new String("1")); l.add(new String("2")); l.add(new String("3")); l.add(new String("4")); l.add(new String("5")); l.add(new String("6")); l.add(new String("7"));Now, copy it to an object array like this −// copying Object[] arr = l.toArray();The following is an example to copy all elements of a ... Read More

An ArrayList can be created from another collection using the java.util.Arrays.asList() method. A program that demonstrates this is given as follows −Example Live Demoimport java.util.ArrayList; import java.util.Arrays; import java.util.List; public class Demo {    public static void main(String args[]) throws Exception {       String str[] = { "John", "Macy", ... Read More

Elements can be filled in a Java long array in a specified range using the java.util.Arrays.fill() method. This method assigns the required long value in the specified range to the long array in Java.The parameters required for the Arrays.fill() method are the array name, the index of the first element ... Read More

Create a TreeSet and add elements −TreeSet tSet = new TreeSet(); tSet.add("TV"); tSet.add("Radio"); tSet.add("Internet");Now, let us copy it to object array −Object[] arr = tSet.toArray(); for (Object ob: arr) {    System.out.println(ob); }The following is an example to copy all elements in TreeSet to an Object Array −Example Live Demoimport java.util.*; ... Read More

To remove the lowest element, use the pollFirst() method.Create a TreeSet and add elements to it −TreeSet tSet = new TreeSet(); tSet.add("78"); tSet.add("56"); tSet.add("88"); tSet.add("12");Now, remove the lowest element −tSet.pollFirst()The following is an example to remove lowest element in Java TreeSet −Example Live Demoimport java.util.*; public class Demo { ... Read More