Struct flate2::bufread::DeflateEncoder

pub struct DeflateEncoder<R> { /* fields omitted */ }

A DEFLATE encoder, or compressor.

This structure consumes a BufRead interface, reading uncompressed data from the underlying reader, and emitting compressed data.

Examples

use std::io::prelude::*;
use std::io;
use flate2::Compression;
use flate2::bufread::DeflateEncoder;
use std::fs::File;
use std::io::BufReader;

// Opens sample file, compresses the contents and returns a Vector
fn open_hello_world() -> io::Result<Vec<u8>> {
   let f = File::open("examples/hello_world.txt")?;
   let b = BufReader::new(f);
   let mut deflater = DeflateEncoder::new(b, Compression::fast());
   let mut buffer = Vec::new();
   deflater.read_to_end(&mut buffer)?;
   Ok(buffer)
}

Implementations

impl<R: BufRead> DeflateEncoder<R>

pub fn new(r: R, level: Compression) -> DeflateEncoder<R>

Creates a new encoder which will read uncompressed data from the given stream and emit the compressed stream.

impl<R> DeflateEncoder<R>

pub fn reset(&mut self, r: R) -> R

Resets the state of this encoder entirely, swapping out the input stream for another.

This function will reset the internal state of this encoder and replace the input stream with the one provided, returning the previous input stream. Future data read from this encoder will be the compressed version of r’s data.

pub fn get_ref(&self) -> &R

Acquires a reference to the underlying reader

pub fn get_mut(&mut self) -> &mut R

Acquires a mutable reference to the underlying stream

Note that mutation of the stream may result in surprising results if this encoder is continued to be used.

pub fn into_inner(self) -> R

Consumes this encoder, returning the underlying reader.

pub fn total_in(&self) -> u64

Returns the number of bytes that have been read into this compressor.

Note that not all bytes read from the underlying object may be accounted for, there may still be some active buffering.

pub fn total_out(&self) -> u64

Returns the number of bytes that the compressor has produced.

Note that not all bytes may have been read yet, some may still be buffered.

Trait Implementations

impl<R: Debug> Debug for DeflateEncoder<R>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<R: BufRead> Read for DeflateEncoder<R>

fn read(&mut self, buf: &mut [u8]) -> Result<usize>

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

pub fn read_vectored(
    &mut self,
    bufs: &mut [IoSliceMut<'_>]
) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

pub fn is_read_vectored(&self) -> bool

🔬 This is a nightly-only experimental API. (can_vector)

Determines if this Reader has an efficient read_vectored implementation.

pub unsafe fn initializer(&self) -> Initializer

🔬 This is a nightly-only experimental API. (read_initializer)

Determines if this Reader can work with buffers of uninitialized memory.

pub fn read_to_end(&mut self, buf: &mut Vec<u8, Global>) -> Result<usize, Error>

Read all bytes until EOF in this source, placing them into buf.

pub fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Read all bytes until EOF in this source, appending them to buf.

pub fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Read the exact number of bytes required to fill buf.

pub fn by_ref(&mut self) -> &mut Self

Creates a “by reference” adaptor for this instance of Read.

pub fn bytes(self) -> Bytes<Self>

Transforms this Read instance to an Iterator over its bytes.

pub fn chain<R>(self, next: R) -> Chain<Self, R> where
    R: Read, 

Creates an adaptor which will chain this stream with another.

pub fn take(self, limit: u64) -> Take<Self>

Creates an adaptor which will read at most limit bytes from it.

impl<W: BufRead + Write> Write for DeflateEncoder<W>

fn write(&mut self, buf: &[u8]) -> Result<usize>

Write a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flush this output stream, ensuring that all intermediately buffered contents reach their destination.

pub fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

pub fn is_write_vectored(&self) -> bool

🔬 This is a nightly-only experimental API. (can_vector)

Determines if this Writer has an efficient write_vectored implementation.

pub fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer.

pub fn write_all_vectored(
    &mut self,
    bufs: &mut [IoSlice<'_>]
) -> Result<(), Error>

🔬 This is a nightly-only experimental API. (write_all_vectored)

Attempts to write multiple buffers into this writer.

pub fn write_fmt(&mut self, fmt: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

pub fn by_ref(&mut self) -> &mut Self

Creates a “by reference” adaptor for this instance of Write.