Oracle 1Z0-851 Online Practice Questions and Exam Preparation

Oracle 1Z0-851 Online Questions & Answers

• Question 101:

  Given that Triangle implements Runnable, and:

  31.

  void go() throws Exception {

  32.

  Thread t = new Thread(new Triangle());

  33.

  t.start();

  34.

  for(int x = 1; x < 100000; x++) {

  35.

  //insert code here

  36.

  if(x%100 == 0) System.out.print("g");

  37.

  } }

  38.

  public void run() {

  39.

  try {

  40.

  for(int x = 1; x < 100000; x++) {

  41.

  // insert the same code here

  42.

  if(x%100 == 0) System.out.print("t");

  43.

  }

  44.

  } catch (Exception e) { }

  45.

  }

  Which two statements, inserted independently at both lines 35 and 41, tend to allow both threads to temporarily pause and allow the other thread to execute? (Choose two.)

  A. Thread.wait();
  B. Thread.join();
  C. Thread.yield();
  D. Thread.sleep(1);
  E. Thread.notify();
  C. Thread.yield();
  D. Thread.sleep(1);

• Question 102:

  DRAG DROP

  Select and Place:

  

  

• Question 103:

  Select and Place:

  

  

• Question 104:

  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?

  A. Compilation fails.
  B. An exception is thrown at runtime.
  C. The code executes and prints "running".
  D. The code executes and prints "runningrunning".
  E. The code executes and prints "runningrunningrunning".
  E. The code executes and prints "runningrunningrunning".

• Question 105:

  Given

  11 public interface Status {

  12 /* insert code here */ int MY_VALUE = 10;

  13 } Which three are valid on line

  12?

  (Choose three.)

  A. final
  B. static
  C. native
  D. public
  E. private
  F. abstract
  G. protected
  A. final
  B. static
  D. public

• Question 106:

  Given:

  1.

  public class GC {

  2.

  private Object o;

  3.

  private void doSomethingElse(Object obj) { o = obj; }

  4.

  public void doSomething() {

  5.

  Object o = new Object();

  6.

  doSomethingElse(o);

  7.

  o = new Object();

  8.

  doSomethingElse(null);

  9.

  o = null;

  10.

  }

  11.

  }

  When the doSomething method is called, after which line does the Object created in line 5 become available for garbage collection?

  A. Line 5
  B. Line 6
  C. Line 7
  D. Line 8
  E. Line 9
  F. Line 10
  D. Line 8

• Question 107:

  Given:

  1.

  public class BuildStuff {

  2.

  public static void main(String[] args) {

  3.

  Boolean test = new Boolean(true);

  4.

  Integer x = 343;

  5.

  Integer y = new BuildStuff().go(test, x);

  6.

  System.out.println(y);

  7.

  }

  8.

  int go(Boolean b, int i) {

  9.

  if(b) return (i/7);

  10.

  return (i/49);

  11.

  }

  12.

  }

  What is the result?

  A. 7
  B. 49
  C. 343
  D. Compilation fails.
  E. An exception is thrown at runtime.
  B. 49

• Question 108:

  Which two statements are true? (Choose two.)

  A. It is possible for more than two threads to deadlock at once.
  B. The JVM implementation guarantees that multiple threads cannot enter into a deadlocked state.
  C. Deadlocked threads release once their sleep() method's sleep duration has expired.
  D. Deadlocking can occur only when the wait(), notify(), and notifyAll() methods are used incorrectly.
  E. It is possible for a single-threaded application to deadlock if synchronized blocks are used incorrectly.
  F. If a piece of code is capable of deadlocking, you cannot eliminate the possibility of deadlocking by inserting invocations of Thread.yield().
  A. It is possible for more than two threads to deadlock at once.
  F. If a piece of code is capable of deadlocking, you cannot eliminate the possibility of deadlocking by inserting invocations of Thread.yield().

• Question 109:

  Given:

  11.

  class Converter {

  12.

  public static void main(String[] args) {

  13.

  Integer i = args[0];

  14.

  int j = 12;

  15.

  System.out.println("It is " + (j==i) + " that j==i.");

  16.

  }

  17.

  }

  What is the result when the programmer attempts to compile the code and run it with the command java Converter 12?

  A. It is true that j==i.
  B. It is false that j==i.
  C. An exception is thrown at runtime.
  D. Compilation fails because of an error in line 13.
  D. Compilation fails because of an error in line 13.

• Question 110:

  DRAG DROP

  Select and Place: