Java多种方法实现合并多个list对象列表

public class User {
    private String name;
    private int age;

    public User(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "User{name='" + name + "', age=" + age + "}";
    }
}

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

public class MergeListsExample {

    public static void main(String[] args) {
        List<User> list1 = Arrays.asList(
            new User("Alice", 30),
            new User("Bob", 25)
        );

        List<User> list2 = Arrays.asList(
            new User("Charlie", 35),
            new User("Diana", 28)
        );

        List<User> list3 = Arrays.asList(
            new User("Eve", 22),
            new User("Frank", 31)
        );

        List<List<User>> listOfLists = Arrays.asList(list1, list2, list3);

        // 使用 Stream API 合并列表
        List<User> mergedList = listOfLists.stream()
            .flatMap(List::stream)
            .collect(Collectors.toList());

        // 输出合并后的列表
        mergedList.forEach(System.out::println);
    }
}

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class MergeListsExample {

    public static void main(String[] args) {
        List<User> list1 = Arrays.asList(
            new User("Alice", 30),
            new User("Bob", 25)
        );

        List<User> list2 = Arrays.asList(
            new User("Charlie", 35),
            new User("Diana", 28)
        );

        List<User> list3 = Arrays.asList(
            new User("Eve", 22),
            new User("Frank", 31)
        );

        List<List<User>> listOfLists = Arrays.asList(list1, list2, list3);

        // 使用传统循环合并列表
        List<User> mergedList = new ArrayList<>();
        for (List<User> list : listOfLists) {
            mergedList.addAll(list);
        }

        // 输出合并后的列表
        mergedList.forEach(System.out::println);
    }
}

User{name='Alice', age=30}
User{name='Bob', age=25}
User{name='Charlie', age=35}
User{name='Diana', age=28}
User{name='Eve', age=22}
User{name='Frank', age=31}