example.java

import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

public class HelloWorld{
    
    public static class Person {
        public String name;
        public String address;
        public Integer age;
        
        public Person(String name, String address, Integer age) {
            this.name = name;
            this.address = address;
            this.age = age;
        }
        
        @Override
        public String toString() {
            return name + " " + address + " " + age;
        }
    }

    public static class Result {
        public String name;
        public String address;
        
        public Result(String name, String address) {
            this.name = name;
            this.address = address;
        }
        
        @Override
        public String toString() {
            return name + " " + address;
        }
    }
    
    public static void main(String []args){
        List<Person> people = Arrays.asList(new Person("Hoang", "1", 19), new Person("Hoa", "2", 20));
        
        List<Result> result = people.stream().map(p -> new Result(p.name, p.address)).collect(Collectors.toList());
        
        System.out.println(result);
    }
}