Java Stream How to - Filter Person object by name and collect to Person List

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Question

We would like to know how to filter Person object by name and collect to Person List.

Answer

/* ww w  . j a  va 2 s.  c o  m*/
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

public class Main {

  public static void main(String[] args) throws Exception {
    List<Person> persons =
        Arrays.asList(
            new Person("Max", 18),
            new Person("Peter", 23),
            new Person("Pamela", 23),
            new Person("David", 12));   
    
    List<Person> filtered =
        persons
            .stream()
            .filter(p -> p.name.startsWith("P"))
            .collect(Collectors.toList());

    System.out.println(filtered);    // [Peter, Pamela]
  }

}
class Person {
  String name;
  int age;

  Person(String name, int age) {
      this.name = name;
      this.age = age;
  }

  @Override
  public String toString() {
      return name;
  }
}

The code above generates the following result.

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