1.
Given this method in a class: 21. public String toString() { 22. StringBuffer buffer = new StringBuffer(); 23. buffer.append('<'); 24. buffer.append(this.name); 25. buffer.append('>'); 26. return buffer.toString(); 27. } Which statement is true?
2.
Given classes defined in two different files: 1. package util; 2. public class BitUtils { 3. public static void process(byte[]) { /* more code here */ } 4. } 1. package app; 2. public class SomeApp { 3. public static void main(String[] args) { 4. byte[] bytes = new byte[256]; 5. // insert code here 6. } 7. } What is required at line 5 in class SomeApp to use the process method of BitUtils?
3.
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?
4.
Given: 84. try { 85. ResourceConnection con = resourceFactory.getConnection(); 86. Results r = con.query("GET INFO FROM CUSTOMER"); 87. info = r.getData(); 88. con.close(); 89. } catch (ResourceException re) { 90. errorLog.write(re.getMessage()); 91. } 92. return info; Which statement is true if a ResourceException is thrown on line 86?
5.
A UNIX user named Bob wants to replace his chess program with a new one, but he is not sure where the old one is installed. Bob is currently able to run a Java chess program starting from his home directory /home/bob using the command: java -classpath /test:/home/bob/downloads/*.jar games.Chess Bob's CLASSPATH is set (at login time) to: /usr/lib:/home/bob/classes:/opt/java/lib:/opt/java/lib/*.jar What is a possible location for the Chess.class file?
6.
Given: 10: public class Hello { 11: String title; 12: int value; 13: public Hello() { 14: title += " World"; 15: } 16: public Hello(int value) { 17: this.value = value; 18: title = "Hello"; 19: Hello(); 20: } 21: } and: 30: Hello c = new Hello(5); 31: System.out.println(c.title); What is the result?
7.
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?
8.
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?
9.
Given classes defined in two different files: 1. package packageA; 2. public class Message { 3. String getText() { return "text"; } 4. } and: 1. package packageB; 2. public class XMLMessage extends package
10.
Given: 1. class Pizza { 2. jav