Questões para Certificação JAVA 1 4_pag91

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Certified Java Programmer Mock Exam 91
} 
 
class K { 
 private void m1() { 
 J j = null; 
 for (int i = 0; i 0) { 
 try {wait();} catch (InterruptedException ie) {} 
 } 
 } 
 } 
 public static void main(String[] args) { 
 new K().m1(); 
 } 
} 
When the processing of line 2 begins how many objects of type J that were created at line 1 are eligible for garbage collection? 
a. 0 
b. 1 
c. 4 
d. 5 
e. Can not be determined without more information. 
f. Compiler error. 
g. Run time error. 
h. None of the above. 
 
Question 3 
class Arnold { 
 private H h; 
 private String quote; 
 public String quote() {return quote;} 
 private static int notFinalized; 
 public static int notFinalized() {return notFinalized;} 
 public Arnold(H h, String s) {this.h = h; quote = s; notFinalized++;} 
 public void finalize() { 
 synchronized (h) { 
 notFinalized--; 
 h.arnold(this); 
 h.notify(); 
 } 
 } 
} 
class H { 
 private Arnold arnold; 
 public void arnold(Arnold a) {arnold = a;} 
 public void m1() { 
 arnold = new Arnold(this, "I'll be back!"); 
 arnold = null; 
 System.gc(); 
 synchronized (this) { 
 while (Arnold.notFinalized() > 0) { 
 try {wait();} catch (InterruptedException ie) {} 
 } 
 } 
 System.out.print(arnold.quote()); // 1 
 } 
 public static void main(String[] args) {new H().m1();} 
} 
Which of the following are true statements and which of the following could be a result of attempting to compile and run the program? 
a. A finalizer-reachable or finalizable (also known as resurrectable) object can never become reachable again. 
b. NullPointerException is thrown at line 1. 
c. Prints: I'll be back! 
d. Prints nothing. 
e. Compiler error. 
f. Run time error. 
g. None of the above. 
 
Question 4 
class I { 
 private static int notFinalized; 
 public static int notFinalized() {return notFinalized;} 
 private J observer; 
 private I other; 
 public void other(I i) {other = i;} 
 private String name; 
 public String name() {return name;}