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Trail: Essential Classes
Lesson: Basic I/O
Basic I/O
I/O Streams
Byte Streams
Character Streams
Buffered Streams
Scanning and Formatting
Scanning
Formatting
I/O from the Command Line
Data Streams
Object Streams
File I/O
File Objects
Random Access Files
The New I/O Packages
Summary
Questions and Exercises
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Questions and Exercises: Basic I/O

### Questions

> 1. What class would you use to read a few pieces of data that are at known positions near the end of a large file?

> 2. In a `format` call, what's the best way to indicate a new line?

> 3. How would you append data to the end of a file? Show the constructor for the class you would use and explain your answer.

### Exercises

> 1. Implement a pair of classes, one `Reader` and one `Writer`, that count the number of times a particular character, such as `e`, is read or written. The character can be specified when the stream is created. Write a program to test your classes. You can use `xanadu.txt` as the input file.

> 2. The file `datafile` begins with a single `long` that tells you the offset of a single `int` piece of data within the same file. Using the `RandomAccessFile` class, write a program that gets the `int` piece of data. What is the `int` data?

> Check your answers.

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