The java.util.ArrayList.contains() method can be used to check if a Java ArrayList contains a given item or not. This method has a single parameter i.e. the item whose presence in the ArrayList is tested. Also it returns true if the item is present in the ArrayList and false if the item is not present.A program that demonstrates this is given as follows −Example Live Demoimport java.util.ArrayList; import java.util.List; public class Demo { public static void main(String[] args) { List aList = new ArrayList(); aList.add("A"); ... Read More

TreeSet is a class in Java that implements the Set interface. It stores unique values in a sorted order. It is similar to HashSet, but the difference is that TreeSet stores elements in a sorted manner, while HashSet does not guarantee any order. Our task is to check if a particular value exists in a TreeSet in Java. We can do this using the following methods: Using contains() Method Using Streams API Using contains() Method The contains() method of the TreeSet class is used for checking if a particular value ... Read More

To get the Tail Set from TreeSet, use the tailSet() method. Tail Set begins from a point and returns the elements greater than the element set in the beginning.First, create a TreeSet and add elements −TreeSet set = new TreeSet(); set.add("78"); set.add("56"); set.add("88"); set.add("54"); set.add("76"); set.add("34");Now, get the Tail Set −SortedSet sorted = set.tailSet("56");The following is an example to get Tail Set from TreeSet −Example Live Demoimport java.util.*; public class Demo {    public static void main(String args[]){       TreeSet set = new TreeSet();       set.add("78");       set.add("56");       set.add("88");       ... Read More

Two ArrayList can be compared to check if they are equal or not using the method java.util.ArrayList.equals(). This method has a single parameter i.e. an ArrayList that is compared with the current object. It returns true if the two ArrayList are equal and false otherwise.A program that demonstrates this is given as follows −Example Live Demoimport java.util.ArrayList; import java.util.List; public class Demo { public static void main(String[] args) { List aList1 = new ArrayList(); aList1.add("Sun"); aList1.add("Moon"); ... Read More

To get the sub set from TreeSet, use the subSet() method. Let us first create a TreeSet and add elements to it −TreeSet set = new TreeSet(); set.add("78"); set.add("56"); set.add("88"); set.add("54"); set.add("76"); set.add("34");Let us get the subset now from a range of elements −SortedSet sorted = set.subSet("54", "76");The following is an example to get sub set from Java TreeSet −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]){ TreeSet set = new TreeSet(); set.add("78"); set.add("56"); ... Read More

To get the size of TreeSet, use the size() 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, get the size of the TreeSet −tSet.size()The following is an example to get the size of TreeSet in Java −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]){ TreeSet tSet = new TreeSet(); tSet.add("78"); tSet.add("56"); tSet.add("88"); tSet.add("12"); ... Read More

To remove the highest element, use the pollLast() 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 highest element −tSet.pollLast()The following is an example to remove highest element in Java TreeSet −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]){ TreeSet tSet = new TreeSet(); tSet.add("78"); tSet.add("56"); tSet.add("88"); tSet.add("12"); ... 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 { public static void main(String args[]){ TreeSet tSet = new TreeSet(); tSet.add("78"); tSet.add("56"); tSet.add("88"); tSet.add("12"); ... Read More

To get the last value in TreeSet, use the last() method.First, get the TreeSet and add elements to it −TreeSet tSet = new TreeSet(); tSet.add("10"); tSet.add("20"); tSet.add("30"); tSet.add("40"); tSet.add("50"); tSet.add("60");Now, get the first value −tSet.last()The following is an example to get the last value in TreeSet −Example Live Demoimport java.util.*; public class Demo {   public static void main(String args[]){ TreeSet tSet = new TreeSet(); tSet.add("10"); tSet.add("20"); tSet.add("30"); ... 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.*; public class Demo {    public static void main(String args[]){       TreeSet tSet = new TreeSet();       tSet.add("TV"); tSet.add("Radio"); tSet.add("Internet"); System.out.println("TreeSet elements = "+tSet); ... Read More