Free 1z0-816: Java SE 11 Programmer II Exam Questions and Answers

Given: List<Integer> list = List.of(1, 2, 3, 4, 5, 6); Which two expressions return a stream that executes in parallel when a terminal operation is invoked? (Choose two.)

Select 2 answers.

• AA. list.stream().onClose(() -> { })
• BB. list.stream().unordered()
• CC. list.stream().filter(x -> x > 2).parallel()
• DD. list.parallelStream()
• EE. list.stream().parallel().sequential()

Given: List<String> names = List.of("kiwi", "fig", "apple", "plum", "date"); String s = names.stream() .sorted(Comparator.comparing(String::length) .thenComparing(Comparator.reverseOrder())) .collect(Collectors.joining(",")); System.out.println(s); What is the result?

• AA. fig,kiwi,plum,date,apple
• BB. fig,plum,kiwi,date,apple
• CC. fig,date,kiwi,plum,apple
• DD. Compilation fails.

Given: Stream.of("a", "bb", "ccc") .peek(s -> System.out.print(s + ",")) .filter(s -> s.length() > 1) .findFirst(); What is the output?

• AA. bb,
• BB. a,bb,
• CC. Nothing is printed.
• DD. a,bb,ccc,

Given: UnaryOperator<String> u = s -> s + "!"; IntUnaryOperator i = n -> n + 1; ToIntBiFunction<String, String> t = (a, b) -> a.length() + b.length(); System.out.println(u.apply("hi") + i.applyAsInt(4) + t.applyAsInt("ab", "cde")); What is the result?

• AA. hi!55
• BB. hi!10
• CC. An exception is thrown at runtime.
• DD. Compilation fails.

Given: interface Walker { default String move() { return "walk"; } } interface Swimmer { default String move() { return "swim"; } } class Duck implements Walker, Swimmer { } The Duck class does not compile. Which two changes, applied independently, make it compile? (Choose two.)

Select 2 answers.

• AA. Add public default String move() { return "paddle"; } to Duck.
• BB. Declare Duck as abstract.
• CC. Add public String move() { return "paddle"; } to Duck.
• DD. Add public String move() { return Walker.super.move(); } to Duck.
• EE. Add String move() { return "paddle"; } to Duck.

Given: Function<Integer, Integer> times3 = x -> x * 3; Function<Integer, Integer> plus2 = x -> x + 2; System.out.println(times3.compose(plus2).andThen(times3).apply(1)); What is the result?

• AA. 5
• BB. 9
• CC. 15
• DD. 27

Given: enum Level { LOW(1), MID(5), HIGH(9); private final int v; Level(int v) { this.v = v; } int v() { return v; } } public class Test { public static void main(String[] args) { Level l = Level.valueOf("MID"); System.out.println(l.ordinal() + ":" + l.compareTo(Level.HIGH) + ":" + l.v()); } } What is the result?

• AA. 2:-1:5
• BB. Compilation fails.
• CC. 1:-4:5
• DD. 1:-1:5

Given: BiFunction<Integer, Integer, Integer> f = /* line n1 */; Which lambda expression, inserted at line n1, compiles?

• AA. (var a, b) -> { return a + b; }
• BB. (var a, var b) -> { a + b; }
• CC. (var a, var b) -> { return a + b; }
• DD. (var a, Integer b) -> { return a + b; }

Given that the file out.txt does not exist in the working directory: import java.io.*; import java.nio.file.*; public class Test { public static void main(String[] args) throws IOException { Path p = Path.of("out.txt"); try (BufferedWriter w = Files.newBufferedWriter(p)) { w.write("ab"); w.newLine(); w.write("cd"); } try (BufferedReader r = Files.newBufferedReader(p)) { System.out.println(r.readLine()); System.out.println(r.readLine()); System.out.println(r.readLine()); } } } What is the result?

• AA. ab, cd, then an EOFException is thrown at runtime
• BB. ab, cd, then null, each printed on its own line
• CC. ab, cd, then an empty line, each printed on its own line
• DD. Compilation fails.

Given: public class Outer { private int x = 10; class Inner { int x = 20; void show(int x) { System.out.println(x + " " + this.x + " " + Outer.this.x); } } public static void main(String[] args) { new Outer().new Inner().show(30); } } What is the result?

• AA. 30 20 10
• BB. 30 10 20
• CC. Compilation fails.
• DD. 10 20 30