Tag: technology

Questions Related to technology

Given: 1. public class Threads3 implements Runnable { 2. public void run() { 3. System.out.print("running"); 4. } 5. public static void main(String[] args) { 6. Thread t = new Thread(new Threads3()); 7. t.run(); 8. t.run(); 9. t.start(); 10. } 11. } What is the result?
technology

  1. Compilation fails.

  2. An exception is thrown at runtime.

  3. The code executes and prints "running".

  4. The code executes and prints "runningrunning".

  5. The code executes and prints "runningrunningrunning".

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Correct Option: E

The segment is the smallest unit of information that DL/I can handle.
technology databases

  1. True

  2. False

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Correct Option: A

DBD is physical description of database.
technology databases

  1. True

  2. False

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Correct Option: A

Given: public class NamedCounter { private final String name; private int count; public NamedCounter(String name) { this.name = name; } public String getName() { return name; } public void increment() { count++; } public int getCount() { return count; } public void reset() { count = 0; } } Which three changes should be made to adapt this class to be used safely by multiple threads? (Choose three.)
technology

  1. declare reset() using the synchronized keyword

  2. declare getName() using the synchronized keyword

  3. declare getCount() using the synchronized keyword

  4. declare the constructor using the synchronized keyword

  5. declare increment() using the synchronized keyword

Show answer
Correct Option: A,C,E

Given: 7. void waitForSignal() { 8. Object obj = new Object(); 9. synchronized (Thread.currentThread()) { 10. obj.wait(); 11. obj.notify(); 12. } 13. } Which statement is true?
technology

  1. This code may throw an InterruptedException

  2. This code may throw an IllegalStateException

  3. This code may throw a TimeoutException after ten minutes

  4. This code will not compile unless "obj.wait()" is replaced with "((Thread) obj).wait()".

  5. Reversing the order of obj.wait() and obj.notify() may cause this method to complete normally

  6. A call to notify() or notifyAll() from another thread may cause this method to complete normally

Show answer
Correct Option: B

Given: 1. public class TestOne implements Runnable { 2. public static void main (String[] args) throws Exception { 3. Thread t = new Thread(new TestOne()); 4. t.start(); 5. System.out.print("Started"); 6. t.join(); 7. System.out.print("Complete"); 8. } 9. public void run() { 10. for (int i = 0; i < 4; i++) { 11. System.out.print(i); 12. } 13. } 14. } What can be a result?
technology

  1. Compilation fails.

  2. An exception is thrown at runtime.

  3. The code executes and prints "StartedComplete"

  4. The code executes and prints "StartedComplete0123".

  5. The code executes and prints "Started0123Complete".

Show answer
Correct Option: E

Given: 11. public class Test { 12. public enum Dogs {collie, harrier, shepherd}; 13. public static void main(String [] args) { 14. Dogs myDog = Dogs.shepherd; 15. switch (myDog) { 16. case collie: 17. System.out.print("collie "); 18. case default: 19. System.out.print("retriever "); 20. case harrier: 21. System.out.print("harrier "); 22. } 23. } 24. } What is the result?
technology

  1. harrier

  2. shepherd

  3. retriever

  4. Compilation fails

  5. retriever harrier

  6. An exception is thrown at runtime

Show answer
Correct Option: D

Given: 8. public class test { 9. public static void main(String [] a) { 10. assert a.length == 1; 11. } 12. } Which two will produce an AssertionError? (Choose two.)
technology

  1. java test

  2. java -ea test

  3. java test file1

  4. java -ea test file1

  5. java -ea test file1 file2

  6. java -ea:test test file1

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Correct Option: B,C,E

Given: 10. interface Foo {} 11. class Alpha implements Foo {} 12. class Beta extends Alpha {} 13. class Delta extends Beta { 14. public static void main( String[] args ) { 15. Beta x = new Beta(); 16. // insert code here 17. } 18. } Which code, inserted at line 16, will cause a java.lang.ClassCastException?
technology

  1. Alpha a = x;

  2. Foo f = (Delta)x;

  3. Foo f = (Alpha)x;

  4. Beta b = (Beta)(Alpha)x;

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Correct Option: B

Given: 11. public static Collection get() { 12. Collection sorted = new LinkedList(); 13. sorted.add("B"); sorted.add("C"); sorted.add("A"); 14. return sorted; 15. } 16. public static void main(String[] args) { 17. for (Object obj: get()) { 18. System.out.print(obj + ", "); 19. } 20. } What is the result?
technology

  1. A, B, C,

  2. B, C, A,

  3. Compilation fails.

  4. The code runs with no output

  5. An exception is thrown at runtime.

Show answer
Correct Option: B