单项选择题
import java.io.*；
public class Forest implements Serializable {
private Tree tree = new Tree（）；
public static void main（String [] args） {
Forest f= new Forest（）；
try {
FileOutputStream fs = new FileOutputStream（”Forest.ser”）；
ObjectOutputStream os = new ObjectOutputStream（fs）；
os.writeObject（f）； os.close（）；
} catch （Exception ex） { ex.printStackTrace（）； }
}
}
class Tree { }
What is the result？（）
A. Compilation fails.
B. An exception is thrown at runtime.
C. An instance of Forest is serialized.
D. A instance of Forest and an instance of Tree are both serialized.
相关考题
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单项选择题
Whencomparingjava.io.BufferedWritertojava.io.FileWriter，whichcapabilityexistsasamethodinonlyoneofthetwo？（）
A. closing the stream
B. flushing the stream
C. writing to the stream
D. marking a location in the stream
E. writing a line separator to the stream -
多项选择题
10. class MakeFile { 11. public static void main（String[] args） { 12. try { 13. File directory = new File（”d”）； 14. File file = new File（directory，”f”）； 15. if（!file.exists（）） { 16. file.createNewFile（）； 17. } 18. } catch （IOException e） { 19. e.printStackTrace 20. } 21. } 22. } The current directory does NOT contain a directory named “d.” Which three are true？（）
A. Line 16 is never executed.
B. An exception is thrown at runtime.
C. Line 13 creates a File object named “d”.
D. Line 14 creates a File object named “f‟.
E. Line 13 creates a directory named “d” in the file system.
F. Line 16 creates a directory named “d” and a file “f” within it in the file system.
G. Line 14 creates a file named "f " inside of the directory named “d” in the file system. -
单项选择题
public class Wow { public static void go（short n） {System.out.println（”short”）； } public static void go（Short n） {System.out.println（”SHORT”）；} public static void go（Long n） {System.out.println（” LONG”）； } public static void main（String [] args） { Short y= 6； int z=7； go（y）； go（z）； } } What is the result？（）
A. short LONG
B. SHORT LONG
C. Compilation fails.
D. An exception is thrown at runtime.
