複選題
140 

Which two statements are true if a NullPointerException is thrown on line 3 of class C? (Choose two.)
(A) The application will crash.
(B) The code on line 29 will be executed.
(C) The code on line 5 of class A will execute.
(D) The code on line 5 of class B will execute.
(E) The exception will be propagated back to line 27.

136 What is the result? (A) test (B) Exception (C) Compilation fails. (D) NullPointerException

137 What is the result? (A) X, followed by an Exception. (B) No output, and an Exception is thrown. (C) Compilation fails due to an error on line 14. (D) Compilation fails due to an error on line 16. (E) Compilation fails due to an error on line 17. (AB) X, followed by an Exception, followed by B.

138 Which two code fragments are most likely to cause a StackOverflowError? (Choose two.)  1. int[] x = {1, 2, 3, 4, 5}; for(int y=0; y＜6; y++) System.out.println(x[y]);   2. static int[] x = {7, 6, 54}; static{x[1] = 8; x[4] = 3;}  3. for(int y=10; y＜10; y++) doStuff(y);  4. void doOne(int x){doTwo(x);} void doTwo(int y){doThree(y);} void doThree(int z){doTwo(z);}  5. for(int x=0; x＜1000000000; x++) doStuff(x);  6. void counter(int i){counter(++i);} (A) 12 (B) 46 (C) 23 (D) 156

139 What, inserted at line 12, is the appropriate way to handle a null value?  (A) assert value == null; (B) assert value != null : "value is null"; (C) (D) 

141 What is the result? (A) Exception (B) A, B, Exception (C) Compilation fails because of an error in line 20. (D) Compilation fails because of an error in line 14. (E) A NullPointerException is thrown at runtime.

142 What is the result? (A) restore 400 (B) restore 403 (C) restore 453 (D) Compilation fails. (E) An exception is thrown at runtime.

144 Which capability exists only in java.io.BufferedWriter? (A) Closing an open stream. (B) Flushing an open stream. (C) Writing to an open stream. (D) Writing a line separator to an open stream.

145 Which statement is true? (A) Compilation fails. (B) The file system has a new empty directory named dir. (C) The file system has a new empty directory named newDir. (D) The file system has a directory named dir, containing a file f1.txt. (E) The file system has a directory named newDir, containing a file f1.txt.

146 Which code, inserted at line 14, will allow this class to correctly serialize and deserialize? (A) s.defaultReadObject(); (B) this = s.defaultReadObject(); (C) y = s.readInt(); x = s.readInt(); (D) x = s.readInt(); y = s.readInt();

複選題147 Which code fragment, inserted at line 4, produces the output | 12.345|? (A) System.out.printf("|%7d| \n", d); (B) System.out.printf("|%7f| \n", d); (C) System.out.printf("|%3.7d| \n", d); (D) System.out.printf("|%3.7f| \n", d); (E) System.out.printf("|%7.3d| \n", d); (AB) System.out.printf("|%7.3f| \n", d);