created: 3/21/2006; revised: 08/20/2014, 06/18/2015, 08/22/2016
Instructions: Each question has something left out. A blank represents the missing word(s). Think of the word or phrase that completes the sentence, then click on the buttons to see if you are correct.
1.
When a Scanner
is connected to a disk file the
characters from the file form an
______ stream.
2.
The following connects a Scanner
to the file myStuff.txt
.
File file = new File ("__________" ); Scanner scan = new Scanner ( ______ );
3.
When nextInt()
scans text integers, integers should be
delimited (separated) with
______
or line separator characters.
4.
When using the nextInt()
method of Scanner
,
may input integers have a leading +
?
______
5.
When using the nextInt()
method of Scanner
,
may input numbers have a leading -
?
______
6.
If something goes wrong when Scanner
tries to open a file for reading, an
_________ is thrown.
7.
If nextInt()
encounters characters that cannot be converted into
an int
an
______________________
is thrown.
8.
What value does hasNextInt()
return if a Scanner
has reached the end of a file? ______
9. What is the name for a group of characters delimited by blanks or end of line characters? ______
What "next" method is used to determine if there is another such group in the input stream? ______
What method is used to read such a group from input stream? ______
10. Complete the following program so that it asks the user for a file name, then opens that file as an input stream.
import java.util.Scanner; class OpenInput { public static void main ( String[] args ) { Scanner user = new Scanner( __________ ); System.out.print("Enter a filename: "); String fileName = user.___________.trim() ; File file = new File( ________ ) ; Scanner disk = new Scanner( ______ ); . . . . . } }
11.
The following connects a PrintWriter
to the file myOutput.txt
.
PrintWriter print = new PrintWriter ("___________");
12.
If you use PrintWriter
to send output to a file that already exists
what happens to the characters that are already in the file?
They are ________
with the new characters.
13.
If a PrintWriter
attempts to open a file for which you do
not have writing permission, an ___________ is thrown.
14.
If a main()
method uses PrintWriter
it should start out
public static void main ( String[] args ) _______ __________
15.
At the end of writing a file with PrintWriter
the file should be _______ .
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