Found 9326 Articles for Object Oriented Programming

Use the remove() method to remove a single value from LinkedHashMap −At first, create a LinkedHashMap and add some elements −LinkedHashMap l = new LinkedHashMap(); l.put("1", "Jack"); l.put("2", "Tom"); l.put("3", "Jimmy"); l.put("4", "Morgan"); l.put("5", "Tim"); l.put("6", "Brad");Now, let’s say you need to remove the element 2 from the LinkedHashMap. For that, use the remove() method −Object ob = l.remove("2");The following is an example to remove a value from LinkedHashMap in Java −Example Live Demoimport java.util.*; public class Demo { public static void main(String[] args) { LinkedHashMap l = new LinkedHashMap(); ... 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 like this −l.containsKey(4)The following is an example to check if a particular key exists in LinkedHashMap −Example Live Demoimport java.util.*; public class Demo { public static void main(String[] args) { LinkedHashMap l = new LinkedHashMap(); l.put(1, ... Read More

To clone the IdentityHashMap in Java, use the clone() method.Create an IdentityHashMap and add elements to it −IdentityHashMap m = new IdentityHashMap(); m.put("1", 100); m.put("2", 200); m.put("3", 300); m.put("4", 150); m.put("5", 110);Now get the size of the IdentityHashMap −m.size()The following is an example to clone IdentityHashMap in Java −Example Live Demoimport java.util.*; public class Demo {    public static void main(String[] args) {       IdentityHashMap m = new IdentityHashMap();       m.put("1", 100);       m.put("2", 200);       m.put("3", 300);       m.put("4", 150);       m.put("5", 110);       m.put("6", 50); ... Read More

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 java.util.LinkedHashSet; public class Demo { public static void main(String[] args) { LinkedHashSet hashSet = new LinkedHashSet(); hashSet.add(10); hashSet.add(20); hashSet.add(30); ... Read More

To create NavigableMap from TreeMap. The following is the declaration −NavigableMap n = new TreeMap();Now, add some elements to the NavigableMap created above −n.put("A", 888); n.put("B", 999); n.put("C", 444); n.put("D", 555); n.put("E", 666); n.put("F", 888); n.put("G", 999); n.put("H", 444); n.put("I", 555); n.put("J", 666);The following is an example to create NavigableMap from TreeMap and display it −Example Live Demoimport java.util.*; public class Demo { public static void main(String[] args) { NavigableMap n = new TreeMap(); n.put("A", 888); n.put("B", 999); ... Read More

To remove a specified element from LinkedHashSet, use the remove() and include the element you want to remove as a parameter.First, set LinkedHashSet and add elements −LinkedHashSet hashSet = new LinkedHashSet(); hashSet.add(10); hashSet.add(20); hashSet.add(30); hashSet.add(40); hashSet.add(50); hashSet.add(60);Let us now remove an element −hashSet.remove(10);The following is an example to remove specified element from LinkedHashSet −Example Live Demoimport java.util.LinkedHashSet; public class Demo { public static void main(String[] args) { LinkedHashSet hashSet = new LinkedHashSet(); hashSet.add(10); hashSet.add(20); ... Read More

Use the NavigableMap ceilingEntry() method to returna key-value mapping associated with the least key greater than or equal to the given keyThe following is an example to implement ceilingEntry() method −Example Live Demoimport java.util.*; public class Demo { public static void main(String[] args) { NavigableMap n = new TreeMap(); n.put(5, "Tom"); n.put(9, "John"); n.put(14, "Jamie"); n.put(1, "Tim"); n.put(4, "Jackie"); n.put(15, "Kurt"); n.put(19, "Tiger"); n.put(24, "Jacob"); System.out.println("NavigableMap elements..."+n); System.out.println("Ceiling Entry = " + n.ceilingEntry(11)); } }OutputNavigableMap elements... {1=Tim, 4=Jackie, 5=Tom, 9=John, 14=Jamie, 15=Kurt, 19=Tiger, 24=Jacob} Ceiling Entry = 14=Jamie

The higher() method in NavigableSet returns the least element strictly greater than the given element i.e. 35 here −higher(35);The following is an example to implement the higher method in Java −Example Live Demoimport java.util.NavigableSet; import java.util.TreeSet; public class Demo { public static void main(String[] args) { 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); System.out.println("Returned Value = " + set.higher(35)); } }OutputReturned Value = 40

The floor() method returns the greatest element less than or equal to the given element i.e. 30 here −floor(30)The following is an example to implement the floor method in Java −Example Live Demoimport java.util.NavigableSet; import java.util.TreeSet; public class Demo { public static void main(String[] args) { 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); System.out.println("Returned Value = " + set.floor(30)); } }OutputReturned Value = 25

With Java, you can initialize a set without using add() method.For this create a string array −String arr[] = { "A", "B", "C", "D", "E"};Now, use Set and asList() method to initialize the above string array to our Set −Set s = new HashSet(Arrays.asList(arr));The following is an example to initialize a set without using add() method −Example Live Demoimport java.util.Arrays; import java.util.HashSet; import java.util.Set; public class Demo { public static void main(String[] a) { String arr[] = { "A", "B", "C", "D", "E"}; Set s = ... Read More