如何在 Groovy 中找到密钥

Question

public String find(int number) {
    String name = phoneBookMap.get(number);
    if (name!=null) {
        return name;
    }
    else {
        return -1;
    }
}

If you have the key and the value

name:Jone 
number:1234 
phoneBookMap = [Jone : 1234]

What is the way to find a name only with number ?

Answer 1

You will have to search by value, something like:

String find(int number) {
    phoneBookMap.entrySet().find{it.value == number}?.key ?: -1
}