File I/O - Absolute Java - page 599

Self-Test Exercises (continued)

11. Might the following throw an exception that needs to be caught or declared in
a throws clause?

Scanner inputStream =
new Scanner( new FileInputStream("morestuff.txt"));

(The stream inputStream would be used to read from the text fi le
morestuff.txt . )

Reading a Text File Using BufferedReader
Until the Scanner class was introduced with version 5.0 of Java, the class
BufferedReader was the preferred stream class to use for reading from a text file. It
is still a commonly used class for reading from a text file. The use of BufferedReader
is illustrated in Display 10.7, which contains a program that reads two lines from
a text file named morestuff2.txt and writes them back to the screen. The file
morestuff2.txt is a text file that a person could have created with a text editor or that
a Java program could have created using PrintWriter .
The program opens the text file morestuff2.txt as follows:

Buffered
Reader

opening a file

BufferedReader inputStream =
new BufferedReader( new FileReader("morestuff2.txt"));
The class BufferedReader , like the classes PrintWriter and Scanner , has no
constructor that takes a file name as its argument, so we need to use another class—in
this case, the class FileReader —to convert the file name to an object that can be an
argument to BufferedReader .
An object of the class BufferedReader that is connected to a text file, as in Display 10.7,
has a method named readLine that is like the method nextLine of the Scanner class.
This use of readLine to read from a text file is illustrated in Display 10.7.
Display 10.8 describes some of the methods in the class BufferedReader . Notice
that there are only two methods for reading from a text file, readLine and read . We
have already discussed readLine .

readLine

Display 10.7 Reading Input from a Text File Using BufferedReader (part 1 of 2)

1 import java.io.BufferedReader;
2 import java.io.FileReader;
3 import java.io.FileNotFoundException;
4 import java.io.IOException;

5 public class TextFileInputDemo
6 {
7 public static void main(String[] args)
8 {

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