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Oracle Certified Professional: Java SE Developer 1Z0-831 (Java SE 25) · Domain 9: Using the Java I/O API

Byte and character streams, BufferedReader and BufferedWriter

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Last reviewed September 25, 2026 · Leer en español

The original java.io package, still widely used, organizes I/O into streams (not to be confused with the Stream API). Byte streams read and write raw 8-bit bytes and descend from the abstract classes InputStream and OutputStream. Character streams read and write text as chars and descend from Reader and Writer. The class name tells you which it is: names ending in Stream handle bytes, names ending in Reader or Writer handle characters.

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