Lesson – 9
1. import java.util.*;
import java.util.ArrayList;
import java.util.Collection;
public class Demo{
public static void main(String[] args){
Collection<String> city = new ArrayList<>();
city.add(“Chicago”);
city.add(“Boston”);
city.add(“Austin”);
city.add(“Seattle”);
city.add(“Nashville”);
city.remove(“Austin”);
city.remove(“Chicago”);
System.out.print(city);
}
}
2. import java.util.*;
abstract class Pro<T>{
abstract T mul(T num, T num2);
}
public class Demo{
public static void main(String[] args){
Scanner sc = new Scanner(System.in);
int a = sc.nextInt();
int b = sc.nextInt();
Pro<Integer> obj = new Pro<>(){
Integer mul(Integer x, Integer y){
return x * y;
}
};
Integer m = obj.mul(a,b);
System.out.println(m);
} }
3. import java.util.*;
public class CyclicShiftApp{
public static void main(String[] args){
Scanner scan = new Scanner(System.in);
ArrayList<Integer> list = new ArrayList<Integer>();
while(scan.hasNextInt()){
list.add(scan.nextInt());
}
Integer [] nums = list.toArray(new Integer[0]);
Collections.sort(list);
for(int counter: list){
System.out.println(counter);
}
}
}
4. import java.util.Arrays;
import java.util.List;
public class Wild{
public static void printlist(List<?> list){
System.out.println(list);
}
public static void main(String[] args){
List<Integer> a = Arrays.asList(1,2,3,4,5);
List<Double> b = Arrays.asList(1.1,1.2,1.3,1.4,1.5);
System.out.println(“Integer list: “);
printlist(a);
System.out.println(“Double list: “);
printlist(b);
}
}
Lesson – 10
1. import java.util.Optional;
public class OptionalDemo{
public static void main(String[] args){
String[] str = new String[5];
str[2] = “An instance of the Optional class.”;
Optional<String> empty = Optional.empty();
System.out.println(empty);
Optional<String> value = Optional.of(str[2]);
System.out.println(value);
}
2. import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;
public class Test{
public static void main(String[] args){
List<String> numbers = Arrays.asList(“1”, “2”, “3”, “4”, “5”, “6”, “7”, “8”, “9”, “10”);
List<Integer> odd = numbers.stream().map(s -> Integer.valueOf(s)).filter(number -> number % 2 != 0).collect(Collectors.toList());
System.out.print(“List of odd numbers: ” + odd);
}
}
3. import java.util.stream.Stream;
public class Demo{
public static void main(String[] args){
Stream<String> s = Stream.of(“Panda”, “Racoon”, “Koala”, “Kangaroo”, “Zebra”);
System.out.print(s.count());
}
}
4. import java.util.*;
public class Demo{
public static void main(String[] args){
List<Integer> list = Arrays.asList(-9, -18, 0, 25, 4);
Integer a = list.stream().min(Integer::compare).get();
// To find the minimum number
Integer b = list.stream().max(Integer::compare).get();
// To find the maximum number
System.out.println(“Minimum number: ” + a);
System.out.println(“Maximum number: ” + b);
}
}
5. import java.util.stream.*;
public class GFG{
public static void main(String[] args){
IntStream.iterate(2, i -> i + 2)
.limit(5)
.forEach(System.out::println);
}
}
6. import java.util.stream.Stream;
public class Test{
public static void main(String[] args){
Stream<String> s = Stream.of(“Harry Potter”, “Percy Jackson”, “The Fault in Our Stars”, “Pride and Prejudice”, “Hunger Games”);
s.skip(3).forEach((e) -> System.out.println(e));
}
}
7. import java.util.stream.Stream;
public class Test{
public static void main(String[] args){
Stream<String> s = Stream.of(“Thor”, “Hours”, “Saw”, “Jumanji”, “Frozen”);
s.limit(2).forEach((e) -> System.out.println(e));
}
}
8. import java.util.stream.Stream;
public class Test{
public static void main(String[] args){
Stream<String> s = Stream.of(“Dollar”, “Euro”, “Rupee”, “Dollar”, “Euro”);
s.distinct().forEach((e) -> System.out.println(e));
}
}
9. import java.util.stream.Stream;
public class Test{
public static void main(String[] args){
Stream<String> s = Stream.of(“Arizona”, “Boston”, “Austin”, “New Orleans”, “Memphis”);
s.filter(str -> str.endsWith(“a”)).forEach(System.out::print);
}
}
10. import java.util.stream.Stream;
public class Main {
public static void main(String[] args) {
Stream<String> stream = Stream.of(“J”, “A”, “V”, “A”);
StringBuilder ele = stream.collect(StringBuilder::new, StringBuilder::append, StringBuilder::append);
System.out.print(ele);
}
}
11. import java.util.*;
public class Main {
public static void main(String[] args) {
List<Integer> array = Arrays.asList(5, 2, -1, 0, 6, 3);
int sum = array.stream().reduce(0, (element1, element2) -> element1 + element2);
System.out.print(“The sum of all elements is ” + sum);
}
}
12. import java.util.function.Predicate;
import java.util.stream.Stream;
public class Main{
public static void main(String[] args){
Stream<String> s = Stream.of(“Samsung”, “Nokia”, “Sony”, “Apple”);
s.forEach((e) -> System.out.println(e));
}
}
13. import java.util.function.Predicate;
import java.util.stream.Stream;
public class Main {
public static void main(String[] args) {
Stream<String> stream = Stream.of(“California”, “Los Angeles”, “Seattle”, “Chicago”);
Predicate<String> len = x -> x.length() < 5;
boolean match = stream.noneMatch(len);
System.out.println(match);
}
}
14. import java.util.function.Predicate;
import java.util.stream.Stream;
public class Main {
public static void main(String[] args) {
Stream<String> stream = Stream.of(“India”, “Brazil”, “Russia”, “Germany”, “Dubai”);
Predicate<String> lower = x -> Character.isLowerCase(x.charAt(0));
boolean match = stream.allMatch(lower);
System.out.println(match);
}
}
15. import java.util.function.Predicate;
import java.util.stream.Stream;
public class Main {
public static void main(String[] args) {
Stream<String> stream = Stream.of(“California”, “Los Angeles”, “Seattle”, “Chicago”);
Predicate<String> len = x -> x.length() > 3;
boolean match = stream.allMatch(len);
System.out.println(match);
}
}
16. import java.util.stream.Stream;
public class Main {
public static void main(String[] args) {
Stream<String> s = Stream.of(“Red”, “Blue”, “Green”);
s.findFirst().ifPresent(System.out::println);
}
}
17. import java.util.stream.Stream;
public class Main {
public static void main(String[] args) {
Stream<String> s = Stream.of(“Louis”, “Stacy”, “Lisa”, “Jerome”, “Howard”);
s.findAny().ifPresent(System.out::println);
}
}
18. import java.util.*;
public class SpliteratorDemo{
public static void main(String args[]){
ArrayList<Integer> arrList = new ArrayList<>();
arrList.add(10);
arrList.add(20);
arrList.add(30);
arrList.add(40);
arrList.add(50);
Spliterator<Integer> splitr = arrList.spliterator();
System.out.println(“Elements of the ArrayList: “);
while(splitr.tryAdvance((n) -> System.out.println(n)));
}
}
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