Oracle Oracle Certifications 1Z0-809 Questions & Answers

• Question 91:

  Assume customers.txt is accessible and contains multiple lines.

  Which code fragment prints the contents of the customers.txt file?

  A. Stream stream = Files.find (Paths.get ("customers.txt")); stream.forEach((String c) -> System.out.println(c));

  B. Stream stream = Files.find (Paths.get ("customers.txt")); stream.forEach( c) -> System.out.println(c));

  C. Stream stream = Files.list (Paths.get ("customers.txt")); stream.forEach( c) -> System.out.println(c));

  D. Stream lines = Files.lines (Paths.get ("customers.txt")); lines.forEach( c) -> System.out.println(c));

  Correct Answer: D

• Question 92:

  Given:

  

  and the code fragment:

  

  What is the result?

  A. An exception is thrown at line n2.

  B. 100

  C. A compilation error occurs because the try block is declared without a catch or finally block.

  D. A compilation error occurs at line n1.

  Correct Answer: B

• Question 93:

  Which two methods from the java.util.stream.Stream interface perform a reduction operation? (Choose two.)

  A. count ()

  B. collect ()

  C. distinct ()

  D. peek ()

  E. filter ()

  Correct Answer: AB

  Reference: https://docs.oracle.com/javase/8/docs/api/java/util/stream/package-summary.html

• Question 94:

  Which code fragment is required to load a JDBC 3.0 driver?

  A. Connection con = Connection.getDriver ("jdbc:xyzdata://localhost:3306/EmployeeDB");

  B. Class.forName("org.xyzdata.jdbc.NetworkDriver");

  C. Connection con = DriverManager.getConnection ("jdbc:xyzdata://localhost:3306/EmployeeDB");

  D. DriverManager.loadDriver ("org.xyzdata.jdbc.NetworkDriver");

  Correct Answer: B

• Question 95:

  Given the code fragment: Assume that the value of now is 6:30 in the morning. What is the result?

  

  A. An exception is thrown at run time.

  B. 0

  C. 60

  D. 1

  Correct Answer: C

• Question 96:

  Given the code fragments:

  

  and

  

  What is the result?

  A. The program prints Run... and throws an exception.

  B. A compilation error occurs at line n1.

  C. Run... Call...

  D. A compilation error occurs at line n2.

  Correct Answer: C

• Question 97:

  Given:

  

  Your design requires that:

  fuelLevel of Engine must be greater than zero when the start() method is invoked. The code must terminate if fuelLevel of Engine is less than or equal to zero.

  Which code fragment should be added at line n1 to express this invariant condition?

  A. assert (fuelLevel) : "Terminating...";

  B. assert (fuelLevel > 0) : System.out.println ("Impossible fuel");

  C. assert fuelLevel < 0: System.exit(0);

  D. assert fuelLevel > 0: "Impossible fuel" ;

  Correct Answer: C

• Question 98:

  Given the code fragment:

  

  What is the result?

  A. Val:20 Val:40 Val:60

  B. Val:10 Val:20 Val:30

  C. A compilation error occurs.

  D. Val: Val: Val:

  Correct Answer: A

• Question 99:

  Given the code fragments:

  

  and

  

  What is the result?

  A. France Optional[NotFound]

  B. Optional [France] Optional [NotFound]

  C. Optional[France] Not Found

  D. France Not Found

  Correct Answer: D

• Question 100:

  Given the code fragment:

  

  Which code fragment, when inserted at line n1, enables the code to print /First.txt?

  A. Path iP = new Paths ("/First.txt");

  B. Path iP = Paths.toPath ("/First.txt");

  C. Path iP = new Path ("/First.txt");

  D. Path iP = Paths.get ("/", "First.txt");

  Correct Answer: D