Java 8 Programs Asked In Interview For Experienced Professionals | Java 8 Coding Interview Questions Asked In The Interview.

 Q1)

// Given Two Strings. Find Out the Two Strings are Anagrams or not.

    // Anagram means a String which has same characters present with the another

    // String,

    // Only the sequence of the Characters are different.

package JavaConceptOfDay;

import java.util.stream.Collectors;

import java.util.stream.Stream;

public class AnagramStrings {

    // Given Two Strings. Find Out the Two Strings are Anagrams or not.

    // Anagram means a String which has same characters present with the another

    // String,

    // Only the sequence of the Characters are different.

    public static void main(String[] args) {

        String str1 = "Listen";

        String str2 = "Silent";

        str1 = Stream.of(str1.split("")).map(String::toLowerCase).sorted().collect(Collectors.joining());

        str2 = Stream.of(str2.split("")).map(String::toLowerCase).sorted().collect(Collectors.joining());

        if (str1.equals(str2)) {

            System.out.println("The Two Strings Are anagram to each other");

        } else {

            System.out.println("Not Anagrams");

        }

    }

}

Q2)

// Given A List Of Integers. Make Them In Reverse Order(Descending Order).

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.Comparator;

import java.util.List;

import java.util.stream.Collectors;

public class DecimalsReverseOrder {

   

    // Given A List Of Integers. Make Them In Reverse Order(Descending Order).

    public static void main(String[] args) {

       

        List<Integer> list=Arrays.asList(14,17,19,75,2,4,74);

        List<Integer> revIntegers=list.stream().sorted(Comparator.reverseOrder()).collect(Collectors.toList());

        System.out.println(revIntegers);

    }

}

Q3) / Given List of Strings, Remove those  Strings who are duplicate from the List

package JavaConceptOfDay;

import java.util.List;

import java.util.stream.Collectors;

public class DuplicateElements {

   

    // Given List of Strings, Remove those  Strings who are duplicate from the List

    public static void main(String[] args) {

       

      List<String> list=List.of("Java", "C", "Java", "Python", "Ruby", "C");

      List<String> list2 =list.stream().distinct().collect(Collectors.toList());

      for(String str:list2)

      {

        System.out.print(str + ",");

      }

    }

}

Q4 )

    // Given a List Of String . Find Out the Frequency Of Each String In A List

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.List;

import java.util.Map;

import java.util.function.Function;

import java.util.stream.Collectors;

public class FreOfEachEleList {

   

    // Given a List Of String . Find Out the Frequency Of Each String In A List

    public static void main(String[] args) {

       

        List<String> list=Arrays.asList("C", "C++", "Java", "C++", "Ruby", "Java");

        Map<String, Long> map=list.stream().collect(Collectors.groupingBy(Function.identity(),Collectors.counting()));

        System.out.println(map);

    }

}

Q5)

// Given a String, How do you find the frequncy of Each Character in A String.

package JavaConceptOfDay;

import java.util.Map;

import java.util.Set;

import java.util.function.Function;

import java.util.stream.Collectors;

public class FrequencyOfEachCharacter {

    // Given a String, How do you find the frequncy of Each Character in A String.

    public static void main(String[] args) {

        String str = "Welcome To Java Welcome To Programming";

        Map<Character, Long> map=str.chars().mapToObj(c -> Character.toLowerCase(Character.valueOf((char) c)))

                .collect(Collectors.groupingBy(Function.identity(), Collectors.counting()));

               Set<Map.Entry<Character, Long>> set=map.entrySet();

               for(Map.Entry<Character, Long> entry:set)

               {

                System.out.println("Character ->" + entry.getKey() + "  Occurnace of this ->" + entry.getValue());

               }

    }

}

Q6) // Given a List Of Strings, Join the String with "[" as Prefix

    // and "]" as Prefix use "," as delimiter

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.List;

import java.util.stream.Collectors;

public class JoiningMethod {

     

    // Given a List Of Strings, Join the String with "[" as Prefix

    // and "]" as Prefix use "," as delimiter

   

     public static void main(String[] args) {

       

        List<String> list =Arrays.asList("C", "JAVA", "C++", "Python");

        String str=list.stream().collect(Collectors.joining(", ", "[", "]"));

        System.out.println(str);

     

     }

}

Q7) // Given A List Of Integers, Find out the max and min from the List

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.Comparator;

import java.util.List;

public class MaxAndMinOfNumber {

    // Given A List Of Integers, Find out the max and min from the List

    public static void main(String[] args) {

        List<Integer> list  =Arrays.asList(5,10,78,32,3,45,12,99);

        Integer max=list.stream().max(Comparator.naturalOrder()).get();

        System.out.println("The Maximum Element From An List : " + max);

        Integer min=list.stream().min(Comparator.naturalOrder()).get();

        System.out.println("The Minimum element of List : " + min);

       

    }

}

Q8)

// How to Merge Two Unsorted Arrays into single array without duplicates and

    // with sorting.

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.stream.IntStream;

public class MergerTwoUnsortedArrays {

    // How to Merge Two Unsorted Arrays into single array without duplicates and

    // with sorting.

    public static void main(String[] args) {

        int a [] = {10,2,5,4,9,3};

        int b[] ={24,1,2,5,4,48};

        int []c=IntStream.concat(Arrays.stream(a), Arrays.stream(b)).sorted().distinct().toArray();

        System.out.println("The Mergerd, sorted array without duplicates is :" + Arrays.toString(c));

    }

}

Q9)

// Given List Of Intgers. Find out the Numbers which are multiple of 5

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.List;

public class MultipleOfFive {

    // Given List Of Intgers. Find out the Numbers which are multiple of 5

    public static void main(String[] args) {

        List<Integer> list = Arrays.asList(1, 65, 2, 45, 74, 50, 35, 5);

        list.stream().filter(number -> number % 5 ==0).forEach(System.out::println);

    }

}

Q10)

// Find The Second Largest Element From An Array Using the Java 8 Stream API

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.Comparator;

import java.util.List;

public class SecondLargest {

    // Find The Second Largest Element From An Array Using the Java 8 Stream API

    public static void main(String[] args) {

        List<Integer> list=Arrays.asList(10,25,9,45,78);

        Integer secondHighInteger=list.stream().distinct().sorted(Comparator.reverseOrder()).skip(1).findFirst().get();

        System.out.println("The Second Highest Element From An Array: "+ secondHighInteger);

    }

}

Q11)

// Given a list of intergers, separate out the odd and even numbers from the

    // List.

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.List;

import java.util.Map;

import java.util.Set;

import java.util.stream.Collectors;

public class SeparateOddAndEven {

    // Given a list of intergers, separate out the odd and even numbers from the

    // List.

    public static void main(String[] args) {

        List<Integer> list = Arrays.asList(14, 71, 39, 42, 78, 15, 36, 99);

        Map<Boolean, List<Integer>> map = list.stream().collect(Collectors.partitioningBy(i -> i % 2 == 0));

        Set<Map.Entry<Boolean, List<Integer>>> set = map.entrySet();

        for (Map.Entry<Boolean, List<Integer>> entry : set) {

            System.out.println("---------------------------------");

            if (entry.getKey()) {

                System.out.println("Even Numbers");

            } else {

                System.out.println("Odd Numbers");

            }

            System.out.println("----------------------------------");

            List<Integer> list2 = entry.getValue();

            for (int i : list2) {

                System.out.println(i);

            }

        }

    }

}

Q12) //Merger the two unsorted Array into Single Sorted Array.

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.stream.IntStream;

public class SingleSortedArray {

   

    //Merger the two unsorted Array into Single Sorted Array.

    public static void main(String[] args) {

       

        int a[] ={10,42,7,11};

        int b[] ={25,3,89,14};

        int c[] =IntStream.concat(Arrays.stream(a), Arrays.stream(b)).sorted().toArray();

        System.out.println(Arrays.toString(c));

    }

}

Q13)

// Given a list of Strings , Sort the Strings according to there increasing

    // Order of length.

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.Comparator;

import java.util.List;

import java.util.stream.Collectors;

public class SortString {

    // Given a list of Strings , Sort the Strings according to there increasing

    // Order of length.

    public static void main(String[] args) {

        List<String> list = Arrays.asList("Java", "C", "Python", "C++", "Ruby", "C#", "Selenium");

        List<String> list2 = list.stream().sorted(Comparator.comparing(String::length)).collect(Collectors.toList());

        for (String str : list2) {

            System.out.println(str + " \n");

        }

    }

}

Q14)

// Given an Array find out the Sum And Average Of the Element Of An Array.

package JavaConceptOfDay;

import java.util.Arrays;

public class SumAndAverageArray {

    // Given an Array find out the Sum And Average Of the Element Of An Array.

    public static void main(String[] args) {

        int a [] ={10,45,78,02,15,84,34,25};

        Integer sum=Arrays.stream(a).sum();

        System.out.println("The Sum Of Elements Of An Array are: " + sum);

        double average = Arrays.stream(a).average().getAsDouble();

        System.out.println("The Average Of Elements in an array are : " + average);

       

    }

}

Q15) // Write A Java 8 Progrram To Find out Sum Of All Digits In A Number.

package JavaConceptOfDay;

import java.util.stream.Collectors;

import java.util.stream.Stream;

public class SumOfDigitInNumber {

    // Write A Java 8 Progrram To Find out Sum Of All Digits In A Number.

    public static void main(String[] args) {

        int number = 12345;

       

        Integer sumOfDigits= Stream.of(String.valueOf(number).split("")).collect(Collectors.summingInt(Integer::parseInt));

        System.out.println("The Sum Of All Digits In Number:" + sumOfDigits);

       

    }

}

Q16)

// How do you get Three Maximum and Minimum Numbers From A List.

package JavaConceptOfDay;

import java.util.Arrays;

import java.util.Comparator;

import java.util.List;

import java.util.stream.Collectors;

public class ThreeMaxAndMin {

    // How do you get Three Maximum and Minimum Numbers From A List.

    public static void main(String[] args) {

       

       List<Integer> listOfIntegers=Arrays.asList(10,2,4,86,1,3,45,15,13);

       System.out.println("The Three Minimum Elements Of List: ");

       List<Integer> list1=listOfIntegers.stream().sorted().limit(3).collect(Collectors.toList());

       System.out.print(list1.toString() + "\n");

       System.out.println("The Three Maximum Elements of the List: ");

       List<Integer> list2  =listOfIntegers.stream().sorted(Comparator.reverseOrder()).limit(3).collect(Collectors.toList());

       System.out.print(list2.toString());

    }

   

}