org.apache.hc.core5.http.impl.io

Class ContentLengthInputStream

java.lang.Object

java.io.InputStream

org.apache.hc.core5.http.impl.io.ContentLengthInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class ContentLengthInputStream
extends InputStream

Input stream that cuts off after a defined number of bytes. This class is used to receive content of HTTP messages where the end of the content entity is determined by the value of the Content-Length header. Entities transferred using this stream can be maximum Long.MAX_VALUE long.

Note that this class NEVER closes the underlying stream, even when close gets called. Instead, it will read until the "end" of its limit on close, which allows for the seamless execution of subsequent HTTP 1.1 requests, while not requiring the client to remember to read the entire contents of the response.

Since:

4.0

Constructor Summary

Constructors

Constructor and Description
ContentLengthInputStream(SessionInputBuffer buffer, InputStream inputStream, long contentLength) Default constructor.

Method Summary

Modifier and Type	Method and Description
int	available() Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking by the next invocation of a method for this input stream.
void	close() Reads until the end of the known length of content.
int	read() Read the next byte from the stream
int	read(byte[] b) Read more bytes from the stream.
int	read(byte[] b, int off, int len) Does standard InputStream.read(byte[], int, int) behavior, but also notifies the watcher when the contents have been consumed.
long	skip(long n) Skips and discards a number of bytes from the input stream.

Methods inherited from class java.io.InputStream

mark, markSupported, reset

Methods inherited from class java.lang.Object

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

Constructor Detail

ContentLengthInputStream

public ContentLengthInputStream(SessionInputBuffer buffer,
                                InputStream inputStream,
                                long contentLength)

Default constructor.

Parameters:

buffer - Session input buffer

inputStream - Input stream

contentLength - The maximum number of bytes that can be read from the stream. Subsequent read operations will return -1.

Method Detail

available

public int available()
              throws IOException

Description copied from class: InputStream

Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking by the next invocation of a method for this input stream. The next invocation might be the same thread or another thread. A single read or skip of this many bytes will not block, but may read or skip fewer bytes.

Note that while some implementations of InputStream will return the total number of bytes in the stream, many will not. It is never correct to use the return value of this method to allocate a buffer intended to hold all data in this stream.

A subclass' implementation of this method may choose to throw an IOException if this input stream has been closed by invoking the InputStream.close() method.

The available method for class InputStream always returns 0.

This method should be overridden by subclasses.

Overrides:

available in class InputStream

Returns:

an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking or 0 when it reaches the end of the input stream.

Throws:

IOException - if an I/O error occurs.

close

public void close()
           throws IOException

Reads until the end of the known length of content.

Does not close the underlying socket input, but instead leaves it primed to parse the next response.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class InputStream

Throws:

IOException - If an IO problem occurs.

read

public int read()
         throws IOException

Read the next byte from the stream

Specified by:

read in class InputStream

Returns:

The next byte or -1 if the end of stream has been reached.

Throws:

IOException - If an IO problem occurs

See Also:

InputStream.read()

read

public int read(byte[] b)
         throws IOException

Read more bytes from the stream.

Overrides:

read in class InputStream

Parameters:

b - The byte array to put the new data in.

Returns:

The number of bytes read into the buffer.

Throws:

IOException - If an IO problem occurs

See Also:

InputStream.read(byte[])

read

public int read(byte[] b,
                int off,
                int len)
         throws IOException

Does standard InputStream.read(byte[], int, int) behavior, but also notifies the watcher when the contents have been consumed.

Overrides:

read in class InputStream

Parameters:

b - The byte array to fill.

off - Start filling at this position.

len - The number of bytes to attempt to read.

Returns:

The number of bytes read, or -1 if the end of content has been reached.

Throws:

IOException - Should an error occur on the wrapped stream.

See Also:

InputStream.read()

skip

public long skip(long n)
          throws IOException

Skips and discards a number of bytes from the input stream.

Overrides:

skip in class InputStream

Parameters:

n - The number of bytes to skip.

Returns:

The actual number of bytes skipped. ≤ 0 if no bytes are skipped.

Throws:

IOException - If an error occurs while skipping bytes.

See Also:

InputStream.skip(long)