Practice 70 Java Streams Programming Questions

Practice 70 Java Streams Programming Questions

Q1. Write a Java program using streams to calculate the sum of a list of integers.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
Sum = 15  

Q2. Write a Java program using streams to find the maximum number from a list of integers.  
Input:  
List = [10, 20, 30, 40, 50]  
Expected Output:  
Max = 50  

Q3. Write a Java program using streams to filter out all even numbers from a list.  
Input:  
List = [1, 2, 3, 4, 5, 6, 7]  
Expected Output:  
[1, 3, 5, 7]  

Q4. Write a Java program using streams to find the average of a list of integers.  
Input:  
List = [10, 20, 30, 40]  
Expected Output:  
Average = 25.0  

Q5. Write a Java program using streams to check if all elements in a list are positive.  
Input:  
List = [1, 2, 3, 4]  
Expected Output:  
true  

Q6. Write a Java program using streams to check if any element in a list is greater than 10.  
Input:  
List = [1, 2, 5, 8]  
Expected Output:  
false  

Q7. Write a Java program using streams to sort a list of integers in ascending order.  
Input:  
List = [5, 3, 7, 2]  
Expected Output:  
[2, 3, 5, 7]  

Q8. Write a Java program using streams to find the first element in a list of integers greater than 5.  
Input:  
List = [1, 2, 3, 4, 6, 7]  
Expected Output:  
6  

Q9. Write a Java program using streams to remove duplicates from a list of integers.  
Input:  
List = [1, 2, 3, 1, 4, 5, 2]  
Expected Output:  
[1, 2, 3, 4, 5]  

Q10. Write a Java program using streams to convert a list of strings to uppercase.  
Input:  
List = ["java", "streams", "example"]  
Expected Output:  
[JAVA, STREAMS, EXAMPLE]  

Q11. Write a Java program using streams to count the number of even numbers in a list.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
2  

Q12. Write a Java program using streams to concatenate all strings in a list into one string.  
Input:  
List = ["Java", "Streams", "Example"]  
Expected Output:  
JavaStreamsExample  

Q13. Write a Java program using streams to find the longest string in a list.  
Input:  
List = ["Java", "Streams", "Example"]  
Expected Output:  
Streams  

Q14. Write a Java program using streams to map a list of integers to their square values.  
Input:  
List = [1, 2, 3, 4]  
Expected Output:  
[1, 4, 9, 16]  

Q15. Write a Java program using streams to get all strings from a list that start with the letter 'J'.  
Input:  
List = ["Java", "Streams", "Jungle", "Python"]  
Expected Output:  
[Java, Jungle]  

Q16. Write a Java program using streams to find the product of all integers in a list.  
Input:  
List = [2, 3, 4]  
Expected Output:  
24  

Q17. Write a Java program using streams to get the first 3 elements from a list.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
[1, 2, 3]  

Q18. Write a Java program using streams to find the sum of even numbers in a list.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
6  

Q19. Write a Java program using streams to get the distinct characters from a string.  
Input:  
str = "java"  
Expected Output:  
[j, a, v]  

Q20. Write a Java program using streams to sort a list of strings in descending order.  
Input:  
List = ["apple", "banana", "cherry"]  
Expected Output:  
[cherry, banana, apple]  

Q21. Write a Java program using streams to check if any element in a list is a palindrome.  
Input:  
List = ["madam", "hello", "level"]  
Expected Output:  
true  

Q22. Write a Java program using streams to find the sum of all odd numbers in a list.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
9  

Q23. Write a Java program using streams to find the maximum length string in a list.  
Input:  
List = ["java", "streams", "example"]  
Expected Output:  
streams  

Q24. Write a Java program using streams to get the square of each number in a list greater than 5.  
Input:  
List = [2, 6, 7, 3]  
Expected Output:  
[36, 49]  

Q25. Write a Java program using streams to sort a list of integers in descending order.  
Input:  
List = [10, 5, 20, 15]  
Expected Output:  
[20, 15, 10, 5]  

Q26. Write a Java program using streams to check if all strings in a list have a length greater than 3.  
Input:  
List = ["java", "streams", "example"]  
Expected Output:  
true  

Q27. Write a Java program using streams to find the sum of squares of all numbers in a list.  
Input:  
List = [1, 2, 3, 4]  
Expected Output:  
30  

Q28. Write a Java program using streams to filter out all strings from a list that have length greater than 5.  
Input:  
List = ["java", "streams", "example", "python"]  
Expected Output:  
[python]  

Q29. Write a Java program using streams to create a new list where each number in the original list is doubled.  
Input:  
List = [1, 2, 3, 4]  
Expected Output:  
[2, 4, 6, 8]  

Q30. Write a Java program using streams to find the first 2 even numbers in a list.  
Input:  
List = [1, 2, 3, 4, 5, 6]  
Expected Output:  
[2, 4]  

Q31. Write a Java program using streams to return the first string that contains the letter 'e' from a list.  
Input:  
List = ["java", "streams", "example", "hello"]  
Expected Output:  
java  

Q32. Write a Java program using streams to filter a list of strings that contains the substring "Java".  
Input:  
List = ["Java", "JavaScript", "Python", "JavaBeans"]  
Expected Output:  
[Java, JavaScript, JavaBeans]  

Q33. Write a Java program using streams to find the count of strings in a list that contain the letter 'a'.  
Input:  
List = ["apple", "banana", "cherry", "date"]  
Expected Output:  
3  

Q34. Write a Java program using streams to get the sum of the first 3 elements in a list.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
6  

Q35. Write a Java program using streams to find the largest number less than 50 in a list.  
Input:  
List = [10, 20, 30, 40, 50, 60]  
Expected Output:  
40  

Q36. Write a Java program using streams to find if there is any string that starts with 'J'.  
Input:  
List = ["Java", "python", "JavaScript", "C++"]  
Expected Output:  
true  

Q37. Write a Java program using streams to convert a list of integers into a list of their binary representations.  
Input:  
List = [2, 3, 4]  
Expected Output:  
[10, 11, 100]  

Q38. Write a Java program using streams to remove all elements that are greater than 10 from a list.  
Input:  
List = [5, 12, 3, 8, 15]  
Expected Output:  
[5, 3, 8]  

Q39. Write a Java program using streams to check if there is any number divisible by both 3 and 5 in a list.  
Input:  
List = [2, 3, 5, 15, 7]  
Expected Output:  
true  

Q40. Write a Java program using streams to create a list of the squares of all numbers less than 5.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
[1, 4, 9, 16]  

Q41. Write a Java program using streams to reverse the order of elements in a list.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
[5, 4, 3, 2, 1]  

Q42. Write a Java program using streams to check if all numbers in a list are even.  
Input:  
List = [2, 4, 6, 8]  
Expected Output:  
true  

Q43. Write a Java program using streams to find the sum of all numbers divisible by 3 in a list.  
Input:  
List = [1, 2, 3, 4, 5, 6]  
Expected Output:  
9  

Q44. Write a Java program using streams to find the second largest number in a list.  
Input:  
List = [2, 3, 5, 7, 6]  
Expected Output:  
6  

Q45. Write a Java program using streams to filter and get all strings that end with the letter 'e'.  
Input:  
List = ["apple", "banana", "cherry", "orange"]  
Expected Output:  
[apple, orange]  

Q46. Write a Java program using streams to find the average of odd numbers in a list.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
3.0  

Q47. Write a Java program using streams to flatten a list of lists into a single list.  
Input:  
List = [[1, 2], [3, 4], [5, 6]]  
Expected Output:  
[1, 2, 3, 4, 5, 6]  

Q48. Write a Java program using streams to find the sum of all odd numbers less than 20 in a list.  
Input:  
List = [5, 10, 15, 20]  
Expected Output:  
20  

Q49. Write a Java program using streams to get the smallest number greater than 10 from a list.  
Input:  
List = [3, 8, 12, 5]  
Expected Output:  
12  

Q50. Write a Java program using streams to remove all null values from a list.  
Input:  
List = [1, null, 2, null, 3]  
Expected Output:  
[1, 2, 3]  

Q51. Write a Java program using streams to group a list of integers based on whether they are even or odd.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
{odd=[1, 3, 5], even=[2, 4]}  

Q52. Write a Java program using streams to convert a list of strings into a list of their lengths.  
Input:  
List = ["java", "streams", "example"]  
Expected Output:  
[4, 7, 7]  

Q53. Write a Java program using streams to find if there is any number greater than 100 in a list.  
Input:  
List = [50, 80, 120, 30]  
Expected Output:  
true  

Q54. Write a Java program using streams to partition a list of integers into odd and even numbers.  
Input:  
List = [1, 2, 3, 4, 5]  
Expected Output:  
{false=[2, 4], true=[1, 3, 5]}  

Q55. Write a Java program using streams to find the average of all even numbers greater than 10 in a list.  
Input:  
List = [5, 12, 8, 20]  
Expected Output:  
16.0  

Q56. Write a Java program using streams to check if all strings in a list contain the letter 'a'.  
Input:  
List = ["apple", "banana", "cherry"]  
Expected Output:  
false  

Q57. Write a Java program using streams to find the first string that contains more than 5 characters.  
Input:  
List = ["java", "streams", "example"]  
Expected Output:  
streams  

Q58. Write a Java program using streams to find the sum of the lengths of all strings in a list.  
Input:  
List = ["java", "streams", "example"]  
Expected Output:  
16  

Q59. Write a Java program using streams to filter out all strings that start with 'j' from a list.  
Input:  
List = ["java", "javaScript", "python"]  
Expected Output:  
[python]  

Q60. Write a Java program using streams to check if a list of integers contains any number divisible by both 3 and 5.  
Input:  
List = [10, 15, 30]  
Expected Output:  
true  

Q61. Write a Java program using streams to find the first string with more than 3 characters.  
Input:  
List = ["a", "bb", "abc", "def"]  
Expected Output:  
abc  

Q62. Write a Java program using streams to filter and return only positive numbers from a list.  
Input:  
List = [-1, 2, -3, 4, 5]  
Expected Output:  
[2, 4, 5]  

Q63. Write a Java program using streams to find the count of words that contain the letter 'e' in a list.  
Input:  
List = ["apple", "banana", "cherry", "date"]  
Expected Output:  
3  

Q64. Write a Java program using streams to get the distinct characters from a string in a list.  
Input:  
str = "apple"  
Expected Output:  
[a, p, l, e]  

Q65. Write a Java program using streams to create a new list of strings with all elements in uppercase.  
Input:  
List = ["java", "streams", "example"]  
Expected Output:  
[JAVA, STREAMS, EXAMPLE]  

Q66. Write a Java program using streams to find the sum of the square roots of all elements in a list.  
Input:  
List = [4, 9, 16]  
Expected Output:  
9.0  

Q67. Write a Java program using streams to find the product of all odd numbers in a list.  
Input:  
List = [1, 3, 5]  
Expected Output:  
15  

Q68. Write a Java program using streams to find the index of the first element greater than 10 in a list.  
Input:  
List = [1, 5, 8, 12, 3]  
Expected Output:  
3  

Q69. Write a Java program using streams to get a list of numbers in a range of 1 to 10 (inclusive).  
Input:  
No input  
Expected Output:  
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]  

Q70. Write a Java program using streams to check if any number in a list is a prime number.  
Input:  
List = [1, 4, 5, 6]  
Expected Output:  
true