How to map values in a map in Java 8?

Say I have a Map<String, Integer>. Is there an easy way to get a Map<String, String> from it?

By easy, I mean not like this:

Map<String, String> mapped = new HashMap<>();
for(String key : originalMap.keySet()) {
    mapped.put(key, originalMap.get(key).toString());
}

But rather some one liner like:

Map<String, String> mapped = originalMap.mapValues(v -> v.toString());

But obviously there is no method mapValues.

You need to stream the entries and collect them in a new map:

Map<String, String> result = map.entrySet()
    .stream()
    .collect(Collectors.toMap(Entry::getKey, e -> String.valueOf(e.getValue()));

The easiest way to do so is:

Map<String, Integer> map = new HashMap<>();
Map<String, String> mapped = map.entrySet().stream()
        .collect(Collectors.toMap(Map.Entry::getKey, entry -> String.valueOf(entry.getValue())));

What you do here, is:

1. Obtain a Stream<Map.Entry<String, Integer>>
2. Collect the results in the resulting map:
3. Map the entries to their key.
4. Map the entries to the new values, incorporating String.valueOf.

The reason you cannot do it in a one-liner, is because the Map interface does not offer such, the closest you can get to that is map.replaceAll, but that method dictates that the type should remain the same.