public class

EofSensorInputStream

extends InputStream
implements ConnectionReleaseTrigger
java.lang.Object
   ↳ java.io.InputStream
     ↳ org.apache.http.conn.EofSensorInputStream

Class Overview

A stream wrapper that triggers actions on close() and EOF. Primarily used to auto-release an underlying connection when the response body is consumed or no longer needed.

This class is based on AutoCloseInputStream in HttpClient 3.1, but has notable differences. It does not allow mark/reset, distinguishes different kinds of event, and does not always close the underlying stream on EOF. That decision is left to the watcher.

See Also

Summary

Fields
protected InputStream wrappedStream The wrapped input stream, while accessible.
Public Constructors
EofSensorInputStream(InputStream in, EofSensorWatcher watcher)
Creates a new EOF sensor.
Public Methods
void abortConnection()
Aborts this stream.
int available()
Returns the number of bytes that are available before this stream will block.
void close()
Closes this stream.
int read(byte[] b, int off, int len)
Reads at most length bytes from this stream and stores them in the byte array b starting at offset.
int read(byte[] b)
Reads bytes from this stream and stores them in the byte array b.
int read()
Reads a single byte from this stream and returns it as an integer in the range from 0 to 255.
void releaseConnection()
Same as close().
Protected Methods
void checkAbort()
Detects stream abort and notifies the watcher.
void checkClose()
Detects stream close and notifies the watcher.
void checkEOF(int eof)
Detects EOF and notifies the watcher.
boolean isReadAllowed()
Checks whether the underlying stream can be read from.
[Expand]
Inherited Methods
From class java.io.InputStream
From class java.lang.Object
From interface java.io.Closeable
From interface org.apache.http.conn.ConnectionReleaseTrigger

Fields

protected InputStream wrappedStream

Since: API Level 1

The wrapped input stream, while accessible. The value changes to null when the wrapped stream becomes inaccessible.

Public Constructors

public EofSensorInputStream (InputStream in, EofSensorWatcher watcher)

Since: API Level 1

Creates a new EOF sensor. If no watcher is passed, the underlying stream will simply be closed when EOF is detected or close is called. Otherwise, the watcher decides whether the underlying stream should be closed before detaching from it.

Parameters
in the wrapped stream
watcher the watcher for events, or null for auto-close behavior without notification

Public Methods

public void abortConnection ()

Since: API Level 1

Aborts this stream. This is a special version of close() which prevents re-use of the underlying connection, if any. Calling this method indicates that there should be no attempt to read until the end of the stream.

Throws
IOException

public int available ()

Since: API Level 1

Returns the number of bytes that are available before this stream will block. This implementation always returns 0. Subclasses should override and indicate the correct number of bytes available.

Returns
  • the number of bytes available before blocking.
Throws
IOException

public void close ()

Since: API Level 1

Closes this stream. Concrete implementations of this class should free any resources during close. This implementation does nothing.

Throws
IOException

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

Since: API Level 1

Reads at most length bytes from this stream and stores them in the byte array b starting at offset.

Parameters
b the byte array in which to store the bytes read.
off the initial position in buffer to store the bytes read from this stream.
len the maximum number of bytes to store in b.
Returns
  • the number of bytes actually read or -1 if the end of the stream has been reached.
Throws
IOException

public int read (byte[] b)

Since: API Level 1

Reads bytes from this stream and stores them in the byte array b.

Parameters
b the byte array in which to store the bytes read.
Returns
  • the number of bytes actually read or -1 if the end of the stream has been reached.
Throws
IOException

public int read ()

Since: API Level 1

Reads a single byte from this stream and returns it as an integer in the range from 0 to 255. Returns -1 if the end of the stream has been reached. Blocks until one byte has been read, the end of the source stream is detected or an exception is thrown.

Returns
  • the byte read or -1 if the end of stream has been reached.
Throws
IOException

public void releaseConnection ()

Since: API Level 1

Same as close().

Throws
IOException

Protected Methods

protected void checkAbort ()

Since: API Level 1

Detects stream abort and notifies the watcher. There's not much to detect since this is called by abortConnection. The watcher will only be notified if this stream is aborted for the first time and before EOF has been detected or the stream has been closed gracefully. This stream will be detached from the underlying stream to prevent multiple notifications to the watcher.

Throws
IOException in case of an IO problem on closing the underlying stream

protected void checkClose ()

Since: API Level 1

Detects stream close and notifies the watcher. There's not much to detect since this is called by close. The watcher will only be notified if this stream is closed for the first time and before EOF has been detected. This stream will be detached from the underlying stream to prevent multiple notifications to the watcher.

Throws
IOException in case of an IO problem on closing the underlying stream

protected void checkEOF (int eof)

Since: API Level 1

Detects EOF and notifies the watcher. This method should only be called while the underlying stream is still accessible. Use isReadAllowed to check that condition.
If EOF is detected, the watcher will be notified and this stream is detached from the underlying stream. This prevents multiple notifications from this stream.

Parameters
eof the result of the calling read operation. A negative value indicates that EOF is reached.
Throws
IOException in case of an IO problem on closing the underlying stream

protected boolean isReadAllowed ()

Since: API Level 1

Checks whether the underlying stream can be read from.

Returns
  • true if the underlying stream is accessible, false if this stream is in EOF mode and detached from the underlying stream
Throws
IOException if this stream is already closed