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

Reading and writing text with Files.readAllLines, Files.lines, Files.writeString

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Last reviewed September 25, 2026 · Leer en español

The Files class offers convenient one-call methods for text. They use UTF-8 by default unless you pass a Charset. Choosing the right one depends mostly on file size and whether you need all the data at once.

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