Java 8 stream – why is the filter method not executed?

See English answers > why does java8 stream generate nothing? 3

Stream.of("d2","a2","b1","b3","c")
    .filter(s -> {
        s.startsWith("b");
        System.out.println("filter: " + s);
        return true;
    });

There are no compilation errors and no exceptions Any suggestions?

Solution

Filter is an intermediate operation that is executed only when the stream pipeline ends in a terminal operation

For example:

Stream.of("d2","c")
  .filter(s -> {
        s.startsWith("b");
        System.out.println("filter: " + s);
        return true;
  })
  .forEach (System.out::println);

In fact, your filtering method is useless because it always returns true, so it does not perform filtering