1. List to Map – Collectors.toMap() package com.mkyong.java8 import java.util.ArrayList; import java.util.List; import java.util.Map; import java.util.stream.Collectors; public class TestListMap { public static void main(String[] args) { List<Hosting> list = new ArrayList<>(); list....
import java.util.List; import java.util.Map; public class ConvertMapToList { public static void main(String[] args) { Map<Integer, String> map = new HashMap<>(); map.put(10, "apple"); map.put(20, "orange"); map.put(30, "banana"); map.put(40, "watermelon"); map.put(50,...
import java.util.Map; public class ConvertMapToList { public static void main(String[] args) { Map<Integer, String> map = new HashMap<>(); map.put(10, "apple"); map.put(20, "orange"); map.put(30, "banana"); map.put(40, "watermelon"); map.put(50, "dragonfruit"); System...
Convert List to Map Using Stream and Collectors in Java It is easy to use the lambda function with Stream and Collectors in Java 8 to achieve the above task. The stream() method returns a Stream of Book class objects from the bookList. To collect these elements, we use the collect() ...
util.Map; import java.util.function.Function; import java.util.stream.Collectors; public class ListToMap1 { public static void main(String[] args) { List<String> list = new ArrayList<>(); list.add("Mohan"); list.add("Sohan"); list.add("Mahesh"); Map<String, Object> map = list....
4. with java 8 starting with java 8, we can convert a list into a map using streams and collectors : public map<integer, animal> convertlistafterjava8(list<animal> list) { map<integer, animal> map = list.stream() .collect(collectors.tomap(animal::getid, function.identity())); return...
SimpleMapToList.java packagecom.concretepage;importjava.util.HashMap;importjava.util.List;importjava.util.Map;importjava.util.stream.Collectors;publicclassSimpleMapToList{publicstaticvoidmain(String[]args){Map<Integer,String>map=newHashMap<>();map.put(23,"Mahesh");map.put(10,"Suresh");map.put...
Java 8 stream map() map() method in java 8 stream is used to convert an object of one type to an object of another type or to transform elements of a collection. map() returns a stream which can be converted to an individual object or a collection, such
Employeeemployee=newEmployee(1,"Alex",LocalDate.of(1995,1,2),List.of("Delhi","Nevada"),List.of(newRole(11,"Finance"),newRole(12,"HR")));System.out.println(convertObjectToMapUsingGson(employee));staticMap<String,String>convertObjectToMapUsingGson(Employeeemployee){Gsongson=newGsonBuilder().re...
Here’s an example of how we can create a custom converter using the Java 8 stream API: importjava.util.Arrays;importjava.util.List;importjava.util.stream.Collectors;publicclassStringToListConverter{publicstaticList<Integer>convert(Stringinput){List<Integer>list=Arrays.stream(input.split(","))....