EXPERTY DESIGNED 1Z0-808 PRACTICE TEST

How many String objects are there in the HEAP memory, when control is at Line 9?

1. package com.udayan.oca;

2.  

3. public class Test {

4.      public static void main(String[] args) {

5.          String s1 = new String("Java"); //Line 3

6.          String s2 = "JaVa"; //Line 4

7.          String s3 = "JaVa"; //Line 5

8.          String s4 = "Java"; //Line 6

9.          String s5 = "Java"; //Line 7

10.  

11.          int i = 1; //Line 9

12.  

13.      }

14. }

What will be the result of compiling and executing Test class?

package com.udayan.oca;

public class Test {

     private static void add(double d1, double d2) {

         System.out.println("double version: " + (d1 + d2));

     }

     private static void add(Double d1, Double d2) {

        System.out.println("Double version: " + (d1 + d2));

     }

     public static void main(String[] args) {

         add(10.0, null);

     }

}

Given code of Thought.java file:

1. public class Thought {

2.     /*INSERT*/ {

3.         System.out.println("All is well");

4.     }

5. }

Which 3 options, if used to replace /*INSERT*/, will compile successfully and on execution will print "All is well" on to the console?

Consider below code:

1. //Test.java

2. package com.udayan.oca;

3.  

4. import java.util.ArrayList;

5. import java.util.Iterator;

6. import java.util.List;

7. import java.util.function.Predicate;

8.  

9. class Employee {

10.      private String name;

11.      private int age;

12.      private double salary;

13.  

14.      public Employee(String name, int age, double salary) {

15.          this.name = name;

16.          this.age = age;

17.          this.salary = salary;

18.      }

19.  

20.      public String getName() {

21.          return name;

22.      }

23.  

24.     public int getAge() {

25.          return age;

26.      }

27.  

28.     public double getSalary() {

29.          return salary;

30.      }

31.  

32.     public String toString() {

33.          return name;

34.      }

35. }

36.  

37. public class Test {

38.      public static void main(String [] args) {

39.          List list = new ArrayList<>();

40.          list.add(new Employee("James", 25, 15000));

41.          list.add(new Employee("Lucy", 23, 12000));

42.          list.add(new Employee("Bill", 27, 10000));

43.          list.add(new Employee("Jack", 19, 5000));

44.          list.add(new Employee("Liya", 20, 8000));

45.  

46.          process(list, /*INSERT*/);

47.  

48.          System.out.println(list);

49.      }

50.  

51.      private static void process(List list, Predicate predicate) {

52.          Iterator iterator = list.iterator();

53.          while(iterator.hasNext()) {

54.              if(predicate.test(iterator.next()))

55.              iterator.remove();

56.          }

57.       }

58. }

Which of the following lambda expressions, if used to replace /*INSERT*/, prints [Jack, Liya] on to the console?

Select 2 options.

Consider below codes of 2 java files:

1. //Flyable.java

2. package com.sampleproject.oca;

3.  

4. public interface Flyable {

5.     static int horizontalDegree() { //Line n1

6.         return 20;

7.     }

8.  

9.     default void fly() {

10.         System.out.println("Flying at " + horizontalDegree() + " degrees."); //Line n2

11.     }

12.  

13.     void land();

14. }

1. //Aeroplane.java

2. package com.sampleproject.oca;

3.  

4. public class Aeroplane implements Flyable {

5.     public void land() {

6.         System.out.println("Landing at " + -Flyable.horizontalDegree() + " degrees."); //Line n3

7.     }

8.  

9.     public static void main(String[] args) {

10.         new Aeroplane().fly();

11.         new Aeroplane().land();

12.     }

13. }

What will be the result of compiling and executing Aeroplane class?