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Java remove elements from collection by filtering

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One of the way to remove elements of collection (in this example list) is to use method removeIf Method declaration: default boolean removeIf(Predicate<? super E> filter) Description: Removes all of the elements of this collection that satisfy the given predicate. Errors or runtime exceptions thrown during iteration or by the predicate are relayed to the caller. … Read more

Java asymmetric set difference

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If you need to find difference between two sets you can use method removeAll. The difference will be kept only on the set which is calling the method. Definition: booleanremoveAll(Collection<?> c) Description: Removes from this set all of its elements that are contained in the specified collection (optional operation). If the specified collection is also a … Read more

Java intersection of Sets

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If you need to get only the elements which are common for two sets you can use the method retainAll. The documentation for this method states: “Method signature: boolean retainAll(Collection<?> c) Description: Retains only the elements in this set that are contained in the specified collection (optional operation). In other words, removes from this set all … Read more

Java 17 sort (Comparable) with lambda and Record

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In this example we can see record Person and we use stream’s sorted(Comparator<? super T> comparator) method to sort the List of people by their age. So sorted(Comparator<? super T> comparator) accept as parameter Comparator. For this reason we have to create Comparator and we sort inside by age. The documentation for sorted(Comparator<? super T> comparator) state: Returns … Read more