相关疑难解决方法(0)

当在期间找到重复的键条目时Collectors.toMap(),(o1, o2)调用合并功能.

问题:如何获取导致重复的密钥？

String keyvalp = "test=one\ntest2=two\ntest2=three";

Pattern.compile("\n")
    .splitAsStream(keyval)
    .map(entry -> entry.split("="))
    .collect(Collectors.toMap(
        split -> split[0],
        split -> split[1],
        (o1, o2) -> {
            //TODO how to access the key that caused the duplicate? o1 and o2 are the values only
            //split[0]; //which is the key, cannot be accessed here
        },
    HashMap::new));

在合并函数内部,我想根据键来决定,如果我取消映射,或继续并接受这些值.