Prerequisite : Streams in java
The skip(long N) is a method of java.util.stream.Stream object. This method takes one long (N) as an argument and returns a stream after removing first N elements. skip() can be quite expensive on ordered parallel pipelines, if the value of N is large, because skip(N) is constrained to skip the first N elements in the encounter order and not just any n elements.
Note : If a stream contains less than N elements, then an empty stream is returned.
Syntax :
Stream<T> skip(long N) Where N is the number of elements to be skipped and this function returns new stream as output.
Exception : If the value of N is negative, then IllegalArgumentException is thrown by the function.
Example 1 : Implementation of skip function.
// Java code for skip() functionimport java.util.*; class GFG { // Driver code public static void main(String[] args) { // Creating a list of integers List<Integer> list = new ArrayList<Integer>(); // adding elements in the list list.add(-2); list.add(0); list.add(2); list.add(4); list.add(6); list.add(8); list.add(10); list.add(12); list.add(14); list.add(16); // setting the value of N as 4 int limit = 4; int count = 0; Iterator<Integer> it = list.iterator(); // Iterating through the list of integers while (it.hasNext()) { it.next(); count++; // Check if first four i.e, (equal to N) // integers are iterated. if (count <= limit) { // If yes then remove first N elements. it.remove(); } } System.out.print("New stream is : "); // Displaying new stream for (Integer number : list) { System.out.print(number + " "); } }} |
Output :
New stream is : 6 8 10 12 14 16
Application :
// Java code for skip() functionimport java.util.stream.Stream;import java.util.ArrayList;import java.util.List; class gfg{ // Function to skip the elements of stream upto given range, i.e, 3 public static Stream<String> skip_func(Stream<String> ss, int range){ return ss.skip(range); } // Driver code public static void main(String[] args){ // list to save stream of strings List<String> arr = new ArrayList<>(); arr.add("geeks"); arr.add("for"); arr.add("geeks"); arr.add("computer"); arr.add("science"); Stream<String> str = arr.stream(); // calling function to skip the elements to range 3 Stream<String> sk = skip_func(str,3); sk.forEach(System.out::println); } } |
Output :
computer science
Difference between limit() and skip() :
- The limit() method returns a reduced stream of first N elements but skip() method returns a stream of remaining elements after skipping first N elements.
- limit() is a short-circuiting stateful intermediate operation i.e, when processed with an infinite input, it may produce a finite stream as a result without processing the entire input but skip() is a stateful intermediate operation i.e, it may need to process the entire input before producing a result.
