Oracle Oracle Database 1Z0-809 Questions & Answers

• Question 21:

  Given:

  class UserException extends Exception { }

  class AgeOutOfLimitException extends UserException { }

  and the code fragment:

  class App {

  public void doRegister(String name, int age)

  throws UserException, AgeOutOfLimitException {

  if (name.length () <= 60) {

  throw new UserException ();

  } else if (age > 60) {

  throw new AgeOutOfLimitException ();

  } else {

  System.out.println("User is registered.");

  }

  }

  public static void main(String[ ] args) throws UserException {

  App t = new App ();

  A. doRegister("Mathew", 60); } } What is the result?

  B. User is registered.

  C. An AgeOutOfLimitException is thrown.

  D. A UserException is thrown.

  E. A compilation error occurs in the main method.

  Correct Answer: C

• Question 22:

  Given the code fragment:

  public class Foo {

  public static void main (String [ ] args) {

  Map unsortMap = new HashMap< > ( );

  unsortMap.put (10, "z");

  unsortMap.put (5, "b");

  unsortMap.put (1, "d");

  unsortMap.put (7, "e");

  unsortMap.put (50, "j");

  Map treeMap = new TreeMap (new

  Comparator ( ) {

  @Override public int compare (Integer o1, Integer o2) {return o2.compareTo (o2); } } );

  treeMap.putAll (unsortMap);

  for (Map.Entry entry : treeMap.entrySet () ) {

  System.out.print (entry.getValue () + " ");

  }

  }

  }

  What is the result?

  A. A compilation error occurs.

  B. d b e z j

  C. j z e b d

  D. z b d e j

  Correct Answer: D

• Question 23:

  Given the code fragments:

  class Caller implements Callable {

  String str;

  public Caller (String s) {this.str=s;}

  public String call()throws Exception { return str.concat ("Caller");}

  }

  class Runner implements Runnable {

  String str;

  public Runner (String s) {this.str=s;}

  public void run () { System.out.println (str.concat ("Runner"));}

  }

  and

  public static void main (String[] args) throws InterruptedException, ExecutionException { ExecutorService

  es = Executors.newFixedThreadPool(2);

  Future f1 = es.submit (new Caller ("Call"));

  Future f2 = es.submit (new Runner ("Run"));

  String str1 = (String) f1.get();

  String str2 = (String) f2.get(); //line n1

  System.out.println(str1+ ":" + str2);

  }

  What is the result?

  A. The program prints:

  Run Runner

  Call Caller : null

  And the program does not terminate.

  B. The program terminates after printing: Run Runner Call Caller : Run

  C. A compilation error occurs at line n1.

  D. An Execution is thrown at run time.

  Correct Answer: D

• Question 24:

  Given:

  class Vehicle implements Comparable{

  int vno;

  String name;

  public Vehicle (int vno, String name) {

  this.vno = vno,;

  this.name = name;

  }

  public String toString () {

  return vno + ":" + name;

  }

  public int compareTo(Vehicle o) {

  return this.name.compareTo(o.name);

  }

  and this code fragment:

  Set vehicles = new TreeSet <> ();

  vehicles.add(new Vehicle (10123, "Ford"));

  vehicles.add(new Vehicle (10124, "BMW"));

  System.out.println(vehicles);

  What is the result?

  A. [10123:Ford, 10124:BMW]

  B. [10124:BMW, 10123:Ford]

  C. A compilation error occurs.

  D. A ClassCastException is thrown at run time.

  Correct Answer: A

• Question 25:

  Given that course.txt is accessible and contains:

  Course : : Java

  and given the code fragment:

  public static void main (String[ ] args) {

  int i;

  char c;

  try (FileInputStream fis = new FileInputStream ("course.txt");

  InputStreamReader isr = new InputStreamReader(fis);) {

  while (!isr.close()) { //line n1

  isr.skip(2);

  i = isr.read ();

  c = (char) i;

  System.out.print(c);

  }

  } catch (Exception e) {

  A. printStackTrace(); } } What is the result?

  B. ur :: va

  C. ueJa

  D. The program prints nothing.

  E. A compilation error occurs at line n1.

  Correct Answer: C

• Question 26:

  Given the code fragment:

  List colors = Arrays.asList("red", "green", "yellow");

  Predicate test = n - > {

  System.out.println("Searching...");

  return n.contains("red");

  };

  colors.stream()

  .filter(c -> c.length() >= 3)

  .allMatch(test);

  What is the result?

  A. Searching...

  B. Searching... Searching...

  C. Searching... Searching... Searching...

  D. A compilation error occurs.

  Correct Answer: C

• Question 27:

  Given the definition of the Emp class:

  public class Emp

  private String eName;

  private Integer eAge;

  Emp(String eN, Integer eA) {

  this.eName = eN;

  this.eAge = eA;

  }

  public Integer getEAge () {return eAge;}

  public String getEName () {return eName;}

  }

  and code fragment:

  Listli = Arrays.asList(new Emp("Sam", 20), New Emp("John", 60), New Emp("Jim", 51));

  Predicate agVal = s -> s.getEAge() <= 60; //line n1

  li = li.stream().filter(agVal).collect(Collectors.toList());

  Stream names = li.stream()map.(Emp::getEName); //line n2

  names.forEach(n -> System.out.print(n + " "));

  What is the result?

  A. Sam John Jim

  B. John Jim

  C. A compilation error occurs at line n1.

  D. A compilation error occurs at line n2.

  Correct Answer: C

• Question 28:

  Given:

  class Book {

  int id;

  String name;

  public Book (int id, String name) {

  this.id = id;

  this.name = name;

  }

  public boolean equals (Object obj) { //line n1

  boolean output = false;

  Book b = (Book) obj;

  if (this.id = = b.id) {

  output = true;

  }

  return output;

  }

  }

  and the code fragment:

  Book b1 = new Book (101, "Java Programing");

  Book b2 = new Book (102, "Java Programing");

  System.out.println (b1.equals(b2)); //line n2

  Which statement is true?

  A. The program prints true.

  B. The program prints false.

  C. A compilation error occurs. To ensure successful compilation, replace line n1 with: boolean equals (Book obj) {

  D. A compilation error occurs. To ensure successful compilation, replace line n2 with: System.out.println (b1.equals((Object) b2));

  Correct Answer: B

• Question 29:

  Given the code fragment:

  Path path1 = Paths.get("/app/./sys/");

  Path res1 = path1.resolve("log");

  Path path2 = Paths.get("/server/exe/");

  Path res1 = path2.resolve("/readme/");

  System.out.println(res1);

  System.out.println(res2);

  What is the result?

  A. /app/sys/log /readme/server/exe

  B. /app/log/sys /server/exe/readme

  C. /app/./sys/log /readme

  D. /app/./sys/log /server/exe/readme

  Correct Answer: D

• Question 30:

  Given the code fragment:

  List nL = Arrays.asList("Jim", "John", "Jeff");

  Function funVal = s -> "Hello : ".concat(s);

  nL.Stream()

  .map(funVal)

  .forEach(s-> System.out.print (s));

  What is the result?

  A. Hello : Jim Hello : John Hello : Jeff

  B. Jim John Jeff

  C. The program prints nothing.

  D. A compilation error occurs.

  Correct Answer: C