Description: programming languages Online Quiz - 100 | |
Number of Questions: 20 | |
Created by: Aliensbrain Bot | |
Tags: programming languages |
Which of the following statements are true?
Which two are true about has-a and is-a relationships? (Choose two.)
Given: 11. public class Counter { 12. public static void main(String[] args) { 13. int numArgs = /* insert code here */; 14. } 15. } and the command line: java Counter one fred 42 Which code, inserted at line 13, captures the number of arguments passed into the program?
Given: 34. HashMap props = new HashMap(); 35. props.put(”key45”, “some value”); 36. props.put(”key12”, “some other value”); 37. props.put(”key39”, “yet another value”); 38. Set s = props.keySet(); 39. // insert code here What, inserted at line 39, will sort the keys in the props HashMap?
Which two are true? (Choose two.)
foo and bar are public references available to many other threads. foo refers to a Thread and bar is an Object. The thread foo is currently executing bar.wait(). From another thread, which statement is the most reliable way to ensue that foo will stop executing wait()?
Given: 1. public class TestOne { 2. public static void main (String[] args) throws Exception { 3. Thread.sleep(3000); 4. System.out.println(”sleep”); 5. } 6. } What is the result?
Given: 1. public class Threads5 { 2. public static void main (String[] args) { 3. new Thread(new Runnable() { 4. public void run() { 5. System.out.print(”bar”); 6. }}).start(); 7. } 8. } What is the result?
Given: 11. public static void test(String str) { 12. int check = 4; 13. if (check = str.length()) { 14. System.out.print(str.charAt(check -= 1) +“, “); 15. } else { 16. System.out.print(str.charAt(0) + “, “); 17. } 18. } and the invocation: 21. test(”four”); 22. test(”tee”); 23. test(”to”); What is the result?
Which of the following is correct syntax for an Abstract class ?
Which two are true? (Choose two.)
Given: 11. String test= “a1b2c3”; 12. String[] tokens = test.split(”\d”); 13. for(String s: tokens) System.out.print(s +“ “); What is the result?
Given: 10. public class Foo implements java.io.Serializable { 11. private int x; 12. public int getX() { return x; } 12.publicFoo(int x){this.x=x; } 13. private void writeObject( ObjectOutputStream s) 14. throws IOException { 15. // insert code here 16. } 17. } Which code fragment, inserted at line 15, will allow Foo objects to be correctly serialized and deserialized?
Given: 33. try { 34. // some code here 35. } catch (NullPointerException e1) { 36. System.out.print(”a”); 37. } catch (RuntimeException e2) { 38. System.out.print(”b”); 39. } finally { 40. System.out.print(”c”); 41. } What is the result if a NullPointerException occurs on line 34?
Given: 12. public class Test { 13. public enum Dogs {collie, harrier}; 14. public static void main(String [] args) { 15. Dogs myDog = Dogs.collie; 16. switch (myDog) { 17. case collie: 18. System.out.print(”collie “); 19. case harrier: 20. System.out.print(”harrier “); 21. } 22. } 23. } What is the result?
Given: 11. public static void main(String[] args) { 12. Object obj =new int[] { 1,2,3 }; 13. int[] someArray = (int[])obj; 14. for (int i: someArray) System.out.print(i +“ “) 15. } ‘What is the result?
Which type of Statement can execute parameterized queries?
Given: 11. public static void parse(String str) { 12. try { 13. float f= Float.parseFloat(str); 14. } catch (NumberFormatException nfe) { 15. f= 0; 16. } finally { 17. System.out.println(f); 18. } 19. } 20. public static void main(String[] args) { 21. parse(”invalid”); 22. } What is the result?
Given: 1. package sun.scjp; 2. public enum Color { RED, GREEN, BLUE } 1. package sun.beta; 2. // insert code here 3. public class Beta { 4. Color g = GREEN; 5. public static void main( String[] argv) 6. { System.out.println( GREEN); } 7. } The class Beta and the enum Color are in different packages. Which two code fragments, inserted individually at line 2 of the Beta declaration, will allow this code to compile? (Choose two.)
Which type of driver provides JDBC access via one or more ODBC drivers?