Package org.apache.commons.io.input

# Class UnsynchronizedFilterInputStream

java.lang.Object
java.io.InputStream
org.apache.commons.io.input.UnsynchronizedFilterInputStream

All Implemented Interfaces:
  `Closeable`, `AutoCloseable`

Direct Known Subclasses:
  `UnsynchronizedBufferedInputStream`

public class UnsynchronizedFilterInputStream extends InputStream
An unsynchronized version of `FilterInputStream`, not thread-safe.

Wraps an existing `InputStream` and performs some transformation on the input data while it is being read. Transformations can be anything from a simple byte-wise filtering input data to an on-the-fly compression or decompression of the underlying stream. Input streams that wrap another input stream and provide some additional functionality on top of it usually inherit from this class.

To build an instance, see `UnsynchronizedFilterInputStream.Builder`.

Provenance: Apache Harmony and modified.

Since:
  2.12.0
See Also:
  - `FilterInputStream`

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `static class`
  `UnsynchronizedFilterInputStream.Builder`
  Builds a new `UnsynchronizedFilterInputStream` instance.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `protected InputStream`
  `inputStream`
  The source input stream that is filtered.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `int`
  `available()`
  Returns the number of bytes that are available before this stream will block.
  `static UnsynchronizedFilterInputStream.Builder`
  `builder()`
  Constructs a new `UnsynchronizedFilterInputStream.Builder`.
  `void`
  `close()`
  Closes this stream.
  `void`
  `mark(int readLimit)`
  Sets a mark position in this stream.
  `boolean`
  `markSupported()`
  Indicates whether this stream supports `mark()` and `reset()`.
  `int`
  `read()`
  Reads a single byte from the filtered stream and returns it as an integer in the range from 0 to 255.
  `int`
  `read(byte[] buffer)`
  Reads bytes from this stream and stores them in the byte array `buffer`.
  `int`
  `read(byte[] buffer, int offset, int count)`
  Reads at most `count` bytes from this stream and stores them in the byte array `buffer` starting at `offset`.
  `void`
  `reset()`
  Resets this stream to the last marked location.
  `long`
  `skip(long count)`
  Skips `count` number of bytes in this stream.

  ### Methods inherited from class java.lang.Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Field Details

  - ### inputStream

    protected volatile InputStream inputStream
    The source input stream that is filtered.

- ## Method Details

  - ### builder

    public static UnsynchronizedFilterInputStream.Builder builder()
    Constructs a new `UnsynchronizedFilterInputStream.Builder`.
    Returns:
      a new `UnsynchronizedFilterInputStream.Builder`.

  - ### available

    public int available() throws IOException
    Returns the number of bytes that are available before this stream will block.
    Overrides:
      `available` in class `InputStream`
    Returns:
      the number of bytes available before blocking.
    Throws:
      `IOException` - if an error occurs in this stream.

  - ### close

    public void close() throws IOException
    Closes this stream. This implementation closes the filtered stream.
    Specified by:
      `close` in interface `AutoCloseable`
    Specified by:
      `close` in interface `Closeable`
    Overrides:
      `close` in class `InputStream`
    Throws:
      `IOException` - if an error occurs while closing this stream.

  - ### mark

    public void mark(int readLimit)
    Sets a mark position in this stream. The parameter `readLimit` indicates how many bytes can be read before the mark is invalidated. Sending `reset()` will reposition this stream back to the marked position, provided that `readLimit` has not been surpassed.

    This implementation sets a mark in the filtered stream.

    Overrides:
      `mark` in class `InputStream`
    Parameters:
      `readLimit` - the number of bytes that can be read from this stream before the mark is invalidated.
    See Also:
      - `markSupported()`
      - `reset()`

  - ### markSupported

    public boolean markSupported()
    Indicates whether this stream supports `mark()` and `reset()`. This implementation returns whether or not the filtered stream supports marking.
    Overrides:
      `markSupported` in class `InputStream`
    Returns:
      `true` if `mark()` and `reset()` are supported, `false` otherwise.
    See Also:
      - `mark(int)`
      - `reset()`
      - `skip(long)`

  - ### read

    public int read() throws IOException
    Reads a single byte from the filtered stream and returns it as an integer in the range from 0 to 255. Returns -1 if the end of this stream has been reached.
    Specified by:
      `read` in class `InputStream`
    Returns:
      the byte read or -1 if the end of the filtered stream has been reached.
    Throws:
      `IOException` - if the stream is closed or another IOException occurs.

  - ### read

    public int read(byte[] buffer) throws IOException
    Reads bytes from this stream and stores them in the byte array `buffer`. Returns the number of bytes actually read or -1 if no bytes were read and the end of this stream was encountered. This implementation reads bytes from the filtered stream.
    Overrides:
      `read` in class `InputStream`
    Parameters:
      `buffer` - the byte array in which to store the read bytes.
    Returns:
      the number of bytes actually read or -1 if the end of the filtered stream has been reached while reading.
    Throws:
      `IOException` - if this stream is closed or another IOException occurs.

  - ### read

    public int read(byte[] buffer, int offset, int count) throws IOException
    Reads at most `count` bytes from this stream and stores them in the byte array `buffer` starting at `offset`. Returns the number of bytes actually read or -1 if no bytes have been read and the end of this stream has been reached. This implementation reads bytes from the filtered stream.
    Overrides:
      `read` in class `InputStream`
    Parameters:
      `buffer` - the byte array in which to store the bytes read.
      `offset` - the initial position in `buffer` to store the bytes read from this stream.
      `count` - the maximum number of bytes to store in `buffer`.
    Returns:
      the number of bytes actually read or -1 if the end of the filtered stream has been reached while reading.
    Throws:
      `IOException` - if this stream is closed or another I/O error occurs.

  - ### reset

    public void reset() throws IOException
    Resets this stream to the last marked location. This implementation resets the target stream.
    Overrides:
      `reset` in class `InputStream`
    Throws:
      `IOException` - if this stream is already closed, no mark has been set or the mark is no longer valid because more than `readLimit` bytes have been read since setting the mark.
    See Also:
      - `mark(int)`
      - `markSupported()`

  - ### skip

    public long skip(long count) throws IOException
    Skips `count` number of bytes in this stream. Subsequent `read()`'s will not return these bytes unless `reset()` is used. This implementation skips `count` number of bytes in the filtered stream.
    Overrides:
      `skip` in class `InputStream`
    Parameters:
      `count` - the number of bytes to skip.
    Returns:
      the number of bytes actually skipped.
    Throws:
      `IOException` - if this stream is closed or another IOException occurs.
    See Also:
      - `mark(int)`
      - `reset()`