CHAPTER 85 — Writing to Binary Files

The character-oriented streams (Readers and Writers) translate data between an internal 16-bit format and an external UTF format. This is convenient for many applications. However, this translation is not appropriate for non-character data. This chapter discusses OutputStream and its subclasses which are used for general-purpose output.

Chapter Topics:

• Binary Files
• OutputStream
• FileOutputStream
• BufferedOutputStream
• DataOutputStream
  • writeInt()
  • writeDouble()
  • writeBytes()
• Hexadecimal file dumps.

Most data types use all the bit patterns that can be formed with the eight bits of a byte. A file that contains such data is often called a binary file. A byte from a binary file might hold any possible pattern. (A byte from an ASCII text file is restricted to somewhat less than half of the possible patterns).