Example usage for java.util List stream

Introduction

In this page you can find the example usage for java.util List stream.

Prototype

default Stream<E> stream()

Source Link

Document

Returns a sequential Stream with this collection as its source.

Usage

From source file:Main.java

public static void main(String[] args) {
    List<Trade> trades = TradeUtil.createTrades();

    List<Integer> list = trades.stream().map(t -> t.getQuantity()).collect(Collectors.toList());
    System.out.println("Collect List: " + list);
}

From source file:Main.java

public static void main(String[] args) {

    List<String> friends = Arrays.asList("CSS", "HTML", "Oracle", "Dart");

    //just sort using lambda comparator
    System.out.println("sort:");
    friends.stream().sorted((aName, bName) -> aName.compareTo(bName)).forEach(System.out::println);
}

From source file:Main.java

public static void main(String[] args) {
    List<Person> roster = createRoster();

    Integer totalAge = roster.stream().mapToInt(Person::getAge).sum();

    System.out.println("Sum of ages (sum operation): " + totalAge);

}

From source file:Main.java

public static void main(String[] args) {
    List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5);
    List<Integer> numbers1 = Arrays.asList(1, 2, 3, 4, 5);

    Stream<Integer> s = Stream.concat(numbers.stream(), numbers1.stream());

    System.out.println(s.count());
}

From source file:Main.java

public static void main(String[] args) {

    List<String> friends = Arrays.asList("CSS", "HTML", "Oracle", "Dart");

    //just sort using lambda comparator
    System.out.println("sort:");

    friends.stream().sorted(String::compareTo).forEach(System.out::println);
}

From source file:Main.java

public static void main(String[] args) {
    List<Employee> persons = Employee.persons();
    // Find any male
    Optional<Employee> anyMale = persons.stream().filter(Employee::isMale).findAny();
    if (anyMale.isPresent()) {
        System.out.println("Any male:   " + anyMale.get());
    } else {//from   www  .j a  va 2s.co  m
        System.out.println("No male  found.");
    }
    // Find the first male
    Optional<Employee> firstMale = persons.stream().filter(Employee::isMale).findFirst();
    if (firstMale.isPresent()) {
        System.out.println("First male:   " + anyMale.get());
    } else {
        System.out.println("No male  found.");
    }
}

From source file:Main.java

public static void main(String[] args) {
    List<Person> roster = createRoster();

    Integer totalAgeReduce = roster.stream().map(Person::getAge).reduce(0, (a, b) -> a + b);

    System.out.println("Sum of ages with reduce(identity, accumulator): " + totalAgeReduce);

}

From source file:Main.java

public static void main(String[] args) {

    List<String> friends = Arrays.asList("CSS", "HTML", "Oracle", "Dart");
    Comparator<String> compByLength = (aName, bName) -> aName.length() - bName.length();
    friends.stream().max(compByLength)
            .ifPresent(longest -> System.out.println("\nThe longest name is " + longest));
}

From source file:Main.java

public static void main(String[] args) {
    List<Employee> persons = Employee.persons();

    // Check if all persons are males
    boolean allMales = persons.stream().allMatch(Employee::isMale);
    System.out.println("All  males: " + allMales);

    // Check if any person was born in 1971
    boolean anyoneBornIn1971 = persons.stream().anyMatch(p -> p.getDob().getYear() == 1971);
    System.out.println("Anyone born  in 1971:  " + anyoneBornIn1971);

}

From source file:Main.java

public static void main(String[] argv) {
    List<Person> persons = Arrays.asList(new Person("HTML", 12), new Person("Aim", 34), new Person("John", 23));
    persons.stream().map(Person::getFirstName).filter(name -> name.startsWith("A")).limit(10)
            .forEach(name -> System.out.println(name));
}