The Lists.partition() method in Guava Library is used to divide the original list into sublists of the same size. The method accepts two parameters.
For example: If the original list passed as parameter is [a, b, c, d, e] and the partition size is 3, then the sublists yield are as [[a, b, c], [d, e]].
Syntax:
public static <T> List<List<T>> partition(List<T> list, int size)
Parameters: The method accepts two parameters:
- list: The list which is to be divided into sublists based on the partition size.
- size: The desired size of each sublist. The size of the last sublist may be smaller.
Return Value: The method returns the list of consecutive sublists. Each sublist(except possibly the last one) has the size equal to the partition size.
Exception: The method Lists.partition() throws IllegalArgumentException if partition size is non-positive.
Below examples illustrate the implementation of above method:
Example 1:
// Java code to show implementation of// Guava's Lists.partition() method  import com.google.common.collect.Lists;import java.util.Arrays;import java.util.List;  class GFG {      // Driver's code    public static void main(String[] args)    {        // Creating a List of Integers        List<Integer> myList            = Arrays.asList(1, 2, 3, 4, 5);          // Using Lists.partition() method to divide        // the original list into sublists of the same        // size, which are just views of the original list.        // The final list may be smaller.        List<List<Integer> > lists            = Lists.partition(myList, 2);          // Displaying the sublists        for (List<Integer> sublist: lists)            System.out.println(sublist);    }} |
[1, 2] [3, 4] [5]
Example 2:
// Java code to show implementation of// Guava's Lists.partition() method  import com.google.common.collect.Lists;import java.util.Arrays;import java.util.List;  class GFG {      // Driver's code    public static void main(String[] args)    {          // Creating a List of Characters        List<Character> myList            = Arrays.asList('H', 'E', 'L', 'L', 'O',                            'G', 'E', 'E', 'K', 'S');          // Using Lists.partition() method to divide        // the original list into sublists of the same        // size, which are just views of the original list.        // The final list may be smaller.        List<List<Character> > lists            = Lists.partition(myList, 3);          // Displaying the sublists        for (List<Character> sublist: lists)            System.out.println(sublist);    }} |
[H, E, L] [L, O, G] [E, E, K] [S]
