public static <F,T> List<T> transform(List<F> fromList, Function<? super F,? extends T> function You might want to read up the API docs for Lists.transform() and Function, but basically the caller of the transform provides a Function object that converts an F to a T. For example if you have a List<Integer> intList and you want to … Read more
For people that absolutely need performance, boxing and unboxing and generified collections and whatnot are big no-no’s. The same problem happens in performance computing where you need the same complex to work both for float and double (say some of the method shown in Goldberd’s “What every computer scientist should know about floating-point numbers“ paper). … Read more
No, this method does not exist in Guava and is in fact in our “idea graveyard.” We don’t believe that “is null or empty” is a question you ever really want to be asking about a collection. If a collection might be null, and null should be treated the same as empty, then get all … Read more
I just added this feature to Guava, see here for the Javadoc. Edit: usage example of Multisets.copyHighestCountFirst() as per the original question: Multiset<DeviceType> histogram = getDeviceStats(); for (DeviceType type : Multisets.copyHighestCountFirst(histogram).elementSet()) { System.out.println(type + “: ” + histogram.count(type)); }
This error message… Exception in thread “main” java.lang.NoClassDefFoundError: com/google/common/collect/ImmutableMap at org.openqa.selenium.firefox.FirefoxDriver …implies that the file com/google/common/collect/ImmutableMap might be corrupted or there is some incompatibility between the version of the binaries you are using specifically with the guava version / dependency (maven). You need to take care of a couple of things as follows: In the … Read more
This error message… java.lang.AbstractMethodError: org.openqa.selenium.remote.service.DriverService$Builder.createArgs()Lcom/google/common/collect/ImmutableList; …implies that there is some incompatibility between the version of the binaries you are using specifically with the guava dependency. You are using chrome= 76.0 You are using the following: <dependency> <groupId>org.seleniumhq.selenium</groupId> <artifactId>selenium-chrome-driver</artifactId> <version>3.5.3</version> <scope>test</scope> </dependency> Your Selenium Client version is 3.5.3 which is more then 2 years older. Your … Read more
I would do this with Guava as follows: Ordering<Map.Entry<Key, Value>> entryOrdering = Ordering.from(valueComparator) .onResultOf(new Function<Entry<Key, Value>, Value>() { public Value apply(Entry<Key, Value> entry) { return entry.getValue(); } }).reverse(); // Desired entries in desired order. Put them in an ImmutableMap in this order. ImmutableMap.Builder<Key, Value> builder = ImmutableMap.builder(); for (Entry<Key, Value> entry : entryOrdering.sortedCopy(map.entrySet())) { builder.put(entry.getKey(), … Read more
You can use the Google Collections API for that, recently renamed to Guava, specifically a BiMap A bimap (or “bidirectional map”) is a map that preserves the uniqueness of its values as well as that of its keys. This constraint enables bimaps to support an “inverse view”, which is another bimap containing the same entries … Read more
In my opinion the better choice is Guava (formerly known as Google collections): it’s more modern (has generics) it absolutely follows the Collections API requirements it’s actively maintained CacheBuilder and it’s predecessor MapMaker are just plain awesome Apache Commons Collections is a good library as well, but it has long failed to provide a generics-enabled … Read more