Java 对象转换成带有索引的对象工具类

在操作集合对象时很多场景需要遍历集合，为了方便包装了一下，供参考和记录

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.function.Function;
import java.util.stream.Collectors;


public final class BeanIndexUtil {
    
    public static Map> createIndexListById(List objectItemList, Function idFun) {
        return objectItemList.stream().collect(Collectors.toMap(idFun,
                p -> {
                    List getObjectItemTempList = new ArrayList<>();
                    getObjectItemTempList.add(p);
                    return getObjectItemTempList;
                },
                (List value1, List value2) -> {
                    value1.addAll(value2);
                    return value1;
                }
        ));
    }

    
    public static Map createIndexById(List objectItemList, Function idFun) {
        return objectItemList.stream().collect(Collectors.toMap(idFun, objItem -> objItem));
    }

    
    public static List getIndexById(List objectItemList, Function idFun) {
        return objectItemList.stream().map(idFun).distinct().collect(Collectors.toList());
    }
}

Map> xxxItemMapByType = BeanIndexUtil.createIndexListById(xxxItems, XxxInfo::getXxxxIdType);

Map xxxMap = BeanIndexUtil.createIndexById(xxxList, XxxVo::getId);

List xxxxIds = BeanIndexUtil.getIndexById(xxxList, XxxInfo::getId);

没有太多天分和履历的本分程序猿最终会有归宿吗