How is the filtering of necessary and excess data carried out during processing?

Data filtering during processing in Java typically occurs using conditional operators and collection methods. For example, to filter a list of objects, you can use the Stream API, applying the filter() method with a predicate that determines which data is needed and which is superfluous.

Example:

List<String> names = Arrays.asList("Anna", "Bob", "Alice", "Mike");
List<String> filtered = names.stream()
    .filter(name -> name.startsWith("A"))
    .collect(Collectors.toList());
// filtered will contain "Anna" and "Alice"

Thus, filtering allows you to retain only the necessary data for further processing.