使用对象的属性作为键将List<Object>转换为Map<key，List<Object>>

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class ListToMapConverter {
    public static void main(String[] args) {
        List<Object> objects = new ArrayList<>();
        
        // 假设List<Object>中的对象是Person类的实例，Person有一个属性name作为键
        objects.add(new Person("Alice", 25));
        objects.add(new Person("Bob", 30));
        objects.add(new Person("Alice", 35));
        objects.add(new Person("Bob", 40));
        
        Map<String, List<Object>> resultMap = convertListToMap(objects);
        
        // 打印转换后的Map<key，List<Object>>中的内容
        for (String key : resultMap.keySet()) {
            System.out.println(key + ": " + resultMap.get(key));
        }
    }
    
    public static Map<String, List<Object>> convertListToMap(List<Object> objects) {
        Map<String, List<Object>> resultMap = new HashMap<>();
        
        for (Object obj : objects) {
            // 假设对象有一个名为getName的方法来获取属性值
            String key = ((Person) obj).getName();
            
            if (resultMap.containsKey(key)) {
                resultMap.get(key).add(obj);
            } else {
                List<Object> newList = new ArrayList<>();
                newList.add(obj);
                resultMap.put(key, newList);
            }
        }
        
        return resultMap;
    }
    
    static class Person {
        private String name;
        private int age;
        
        public Person(String name, int age) {
            this.name = name;
            this.age = age;
        }
        
        public String getName() {
            return name;
        }
        
        public int getAge() {
            return age;
        }
        
        @Override
        public String toString() {
            return "Person{" +
                    "name='" + name + '\'' +
                    ", age=" + age +
                    '}';
        }
    }
}