Readable (Java Platform SE 8 )
Keywords: java.lang.Readable interface
Date: 2026-04-17

compact1, compact2, compact3
java.lang

## Interface Readable

- All Known Implementing Classes:
    BufferedReader, CharArrayReader, CharBuffer, FileReader, FilterReader, InputStreamReader, LineNumberReader, PipedReader, PushbackReader, Reader, StringReader

      public interface Readable

  A `Readable` is a source of characters. Characters from a `Readable` are made available to callers of the read method via a `CharBuffer`.
  Since:
    1.5

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method and Description
    --- | ---
    `int` | `read(CharBuffer cb)` Attempts to read characters into the specified character buffer.

- - ### Method Detail

    - #### read

          int read(CharBuffer cb)
            throws IOException

      Attempts to read characters into the specified character buffer. The buffer is used as a repository of characters as-is: the only changes made are the results of a put operation. No flipping or rewinding of the buffer is performed.
      Parameters:
        `cb` - the buffer to read characters into
      Returns:
        The number of `char` values added to the buffer, or -1 if this source of characters is at its end
      Throws:
        `IOException` - if an I/O error occurs
        `NullPointerException` - if cb is null
        `ReadOnlyBufferException` - if cb is a read only buffer

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