1Z0-809 Practice Questions

Given the code fragment: What is the result?

Given: class Student { String course, name, city; public Student (String name, String course, String city) { this.course = course; this.name = name; this.city = city; } public String toString() { return course + “:” + name + “:” + city; } and the code fragment: List stds = Arrays.asList( new Student (“Jessy”, “Java ME”, “Chicago”), new Student (“Helen”, “Java EE”, “Houston”), new Student (“Mark”, “Java ME”, “Chicago”)); stds.stream() .collect(Collectors.groupingBy(Student::getCourse)) .forEach(src, res) -> System.out.println(scr)); What is the result?

Given: class Worker extends Thread { CyclicBarrier cb; public Worker(CyclicBarrier cb) { this.cb = cb; } public void run () { try { cb.await(); System.out.println(“Worker…”); } catch (Exception ex) { } } } class Master implements Runnable { //line n1 public void run () { System.out.println(“Master…”); } } and the code fragment: Master master = new Master(); //line n2 Worker worker = new Worker(cb); worker.start(); You have been asked to ensure that the run methods of both the Worker and Master classes are executed. Which modification meets the requirement?

Given the code fragment: Path file = Paths.get (“courses.txt”); // line n1 Assume the courses.txt is accessible. Which code fragment can be inserted at line n1 to enable the code to print the content of the courses.txt file?

Given that /green.txt and /colors/yellow.txt are accessible, and the code fragment: Path source = Paths.get(“/green.txt); Path target = Paths.get(“/colors/yellow.txt); Files.move(source, target, StandardCopyOption.ATOMIC_MOVE); Files.delete(source); Which statement is true?

Given the code fragment: List str = Arrays.asList (“my”, “pen”, “is”, “your’, “pen”); Predicate test = s -> { int i = 0; boolean result = s.contains (“pen”); System.out.print(i++) + “:”); return result; }; str.stream() .filter(test) .findFirst() .ifPresent(System.out ::print); What is the result?

Which two reasons should you use interfaces instead of abstract classes? (Choose two.)

Given: public interface Moveable { public default void walk (Integer distance) {System.out.println(“Walking”);) public void run(Integer distance); } Which statement is true?

Given the code fragment: What is the result?