Oracle 1Z0-809 Faq 2021

NEW QUESTION 1
Given:

What is the result?

• A. Bar Hello Foo Hello
• B. Bar Hello Baz Hello
• C. Baz Hello
• D. A compilation error occurs in the Daze class.

Answer: C

NEW QUESTION 2
Given the code fragment:
List<Integer> values = Arrays.asList (1, 2, 3); values.stream ()
.map(n -> n*2) //line n1
.p eek(System.out::print) //line n2
.count();
What is the result?

• A. 246
• B. The code produces no output.
• C. A compilation error occurs at line n1.
• D. A compilation error occurs at line n2.

Answer: A

NEW QUESTION 3
Given the code fragment:

Which is the valid definition of the Course enum?

• A. Option A
• B. Option B
• C. Option C
• D. Option D

Answer: A

NEW QUESTION 4
Given the code fragment:
List<String> str = Arrays.asList (“my”, “pen”, “is”, “your’, “pen”); Predicate<String> test = s -> {
int i = 0;
boolean result = s.contains (“pen”);
System.out.print(i++) + “:”); return result;
};
str.stream()
.filter(test)
.findFirst()
.i fPresent(System.out ::print); What is the result?

• A. 0 : 0 : pen
• B. 0 : 1 : pen
• C. 0 : 0 : 0 : 0 : 0 : pen
• D. 0 : 1 : 2 : 3 : 4 :
• E. A compilation error occurs.

Answer: A

NEW QUESTION 5
Given the code fragment:
ZonedDateTime depart = ZonedDateTime.of(2015, 1, 15, 3, 0, 0, 0, ZoneID.of(“UTC-
7”));
ZonedDateTime arrive = ZonedDateTime.of(2015, 1, 15, 9, 0, 0, 0, ZoneID.of(“UTC-
5”));
long hrs = ChronoUnit.HOURS.between(depart, arrive); //line n1 System.out.println(“Travel time is” + hrs + “hours”);
What is the result?

• A. Travel time is 4 hours
• B. Travel time is 6 hours
• C. Travel time is 8 hours
• D. An exception is thrown at line n1.

Answer: A

NEW QUESTION 6
Given the Greetings.properties file, containing:

and given:

What is the result?

• A. Compilation fails.
• B. GOODBY_MSG
• C. Hello, everyone!
• D. Goodbye everyone!
• E. HELLO_MSG

Answer: A

NEW QUESTION 7
Given:
public class Canvas implements Drawable { public void draw () { }
}
public abstract class Board extends Canvas { }
public class Paper extends Canvas { protected void draw (int color) { }
}
public class Frame extends Canvas implements Drawable { public void resize () { }
}
public interface Drawable { public abstract void draw ();
}
Which statement is true?

• A. Board does not compile.
• B. Paper does not compile.
• C. Frame does not compile.
• D. Drawable does not compile.
• E. All classes compile successfully.

Answer: E

NEW QUESTION 8
Given the code fragment:

What is the result?

• A. Word: why what when
• B. Word: why Word: why what Word: why what when
• C. Word: why Word: what Word: when
• D. Compilation fails at line n1.

Answer: A

NEW QUESTION 9
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” ;

Answer: C

NEW QUESTION 10
Given the code fragments:

and

What is the result?

• A. FranceOptional[NotFound]
• B. Optional [France] Optional [NotFound]
• C. Optional[France] Not Found
• D. FranceNot Found

Answer: D

NEW QUESTION 11
Given the code fragment: Stream<List<String>> iStr= Stream.of ( Arrays.asList (“1”, “John”),
Arrays.asList (“2”, null)0;
Stream<<String> nInSt = iStr.flatMapToInt ((x) -> x.stream ()); nInSt.forEach (System.out :: print);
What is the result?

• A. 1John2null
• B. 12
• C. A NullPointerException is thrown at run time.
• D. A compilation error occurs.

Answer: D

NEW QUESTION 12
Given the code fragments:

and

Which two modifications enable to sort the elements of the emps list? (Choose two.)

• A. Replace line n1 withclass Person extends Comparator<Person>
• B. At line n2 insertpublic int compareTo (Person p) { return this.name.compareTo (p.name);}
• C. Replace line n1 withclass Person implements Comparable<Person>
• D. At line n2 insertpublic int compare (Person p1, Person p2) { return p1.name.compareTo (p2.name);}
• E. At line n2 insert:public int compareTo (Person p, Person p2) { return p1.name.compareTo (p2.name);}
• F. Replace line n1 withclass Person implements Comparator<Person>

Answer: CE

NEW QUESTION 13
Which class definition compiles?

• A. Option A
• B. Option B
• C. Option C
• D. Option D

Answer: A

NEW QUESTION 14
Given:
interface Doable {
public void doSomething (String s);
}
Which two class definitions compile? (Choose two.)

• A. public abstract class Task implements Doable { public void doSomethingElse(String s) { }}
• B. public abstract class Work implements Doable { public abstract void doSomething(String s) { } public void doYourThing(Boolean b) { }}
• C. public class Job implements Doable { public void doSomething(Integer i) { }}
• D. public class Action implements Doable { public void doSomething(Integer i) { } public String doThis(Integer j) { }}
• E. public class Do implements Doable { public void doSomething(Integer i) { } public void doSomething(String s) { } public void doThat (String s) { }}

Answer: AE

NEW QUESTION 15
Given:

and the command: java Product 0 What is the result?

• A. An AssertionError is thrown.
• B. A compilation error occurs at line n1.
• C. New Price: 0.0
• D. A NumberFormatException is thrown at run time.

Answer: D

NEW QUESTION 16
Given:

and the code fragment:

What is the result?

• A. [Java EE: Helen:Houston][Java ME: Jessy:Chicago, Java ME: Mark:Chicago]
• B. Java EEJava ME
• C. [Java ME: Jessy:Chicago, Java ME: Mark:Chicago] [Java EE: Helen:Houston]
• D. A compilation error occurs.

Answer: D

NEW QUESTION 17
Given the code fragment: UnaryOperator<Integer> uo1 = s -> s*2; line n1
List<Double> loanValues = Arrays.asList(1000.0, 2000.0); loanValues.stream()
.filter(lv -> lv >= 1500)
.map(lv -> uo1.apply(lv))
.forEach(s -> System.out.print(s + “ “)); What is the result?

• A. 4000.0
• B. 4000
• C. A compilation error occurs at line n1.
• D. A compilation error occurs at line n2.

Answer: D

NEW QUESTION 18
Given the code fragment:

Assume that dbURL, userName, and password are valid.
Which code fragment can be inserted at line n1 to enable the code to print Connection Established?

• A. Properties prop = new Properties(); prop.put (“user”, userName); prop.put (“password”, password);con = DriverManager.getConnection (dbURL, prop);
• B. con = DriverManager.getConnection (userName, password, dbURL);
• C. Properties prop = new Properties(); prop.put (“userid”, userName); prop.put (“password”, password); prop.put(“url”, dbURL);con = DriverManager.getConnection (prop);
• D. con = DriverManager.getConnection (dbURL); con.setClientInfo (“user”, userName); con.setClientInfo (“password”, password);

Answer: A

NEW QUESTION 19
Given the code fragment:

What is the result?

• A. Java EEJava EESE
• B. Java EESE
• C. The program prints either:Java EEJava SE orJava SEJava EE
• D. Java EEJava SE

Answer: D

NEW QUESTION 20
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?

• A. The green.txt file content is replaced by the yellow.txt file content and the yellow.txt file is deleted.
• B. The yellow.txt file content is replaced by the green.txt file content and an exception is thrown.
• C. The file green.txt is moved to the /colors directory.
• D. A FileAlreadyExistsException is thrown at runtime.

Answer: D

NEW QUESTION 21
Given the definition of the Country class: public class country {
public enum Continent {ASIA, EUROPE} String name;
Continent region;
public Country (String na, Continent reg) { name = na, region = reg;
}
public String getName () {return name;} public Continent getRegion () {return region;}
}
and the code fragment:
List<Country> couList = Arrays.asList (
new Country (“Japan”, Country.Continent.ASIA), new Country (“Italy”, Country.Continent.EUROPE),
new Country (“Germany”, Country.Continent.EUROPE)); Map<Country.Continent, List<String>> regionNames = couList.stream ()
.c ollect(Collectors.groupingBy (Country ::getRegion, Collectors.mapping(Country::getName, Collectors.toList())))); System.out.println(regionNames);

• A. {EUROPE = [Italy, Germany], ASIA = [Japan]}
• B. {ASIA = [Japan], EUROPE = [Italy, Germany]}
• C. {EUROPE = [Germany, Italy], ASIA = [Japan]}
• D. {EUROPE = [Germany], EUROPE = [Italy], ASIA = [Japan]}

Answer: B

NEW QUESTION 22
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