Package org.apache.commons.io.input

Class ObservableInputStream.Observer

java.lang.Object

org.apache.commons.io.input.ObservableInputStream.Observer

Direct Known Subclasses:

MessageDigestCalculatingInputStream.MessageDigestMaintainingObserver, MessageDigestInputStream.MessageDigestMaintainingObserver, TimestampedObserver

Enclosing class:

ObservableInputStream

public abstract static class ObservableInputStream.Observer
extends Object

Abstracts observer callback for ObservableInputStreams.

Constructor Summary

Constructors

Constructor	Description
Observer()

Method Summary

Modifier and Type	Method	Description
void	closed()	Called to indicate that the ObservableInputStream has been closed.
void	data(byte[] buffer, int offset, int length)	Called to indicate that InputStream.read(byte[]), or InputStream.read(byte[], int, int) have been called, and are about to invoke data.
void	data(int value)	Called to indicate, that InputStream.read() has been invoked on the ObservableInputStream, and will return a value.
void	error(IOException exception)	Called to indicate that an error occurred on the underlying stream.
void	finished()	Called to indicate that EOF has been seen on the underlying stream.

Methods inherited from class java.lang.Object

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

Constructor Details

Observer

public Observer()

Method Details

closed

public void closed()
            throws IOException

Called to indicate that the ObservableInputStream has been closed.

Throws:

IOException - if an I/O error occurs.

data

public void data(byte[] buffer,
 int offset,
 int length)
          throws IOException

Called to indicate that InputStream.read(byte[]), or InputStream.read(byte[], int, int) have been called, and are about to invoke data.

Parameters:

buffer - The byte array, which has been passed to the read call, and where data has been stored.

offset - The offset within the byte array, where data has been stored.

length - The number of bytes, which have been stored in the byte array.

Throws:

IOException - if an I/O error occurs.

data

public void data(int value)
          throws IOException

Called to indicate, that InputStream.read() has been invoked on the ObservableInputStream, and will return a value.

Parameters:

value - The value, which is being returned. This will never be -1 (EOF), because, in that case, finished() will be invoked instead.

Throws:

IOException - if an I/O error occurs.

error

public void error(IOException exception)
           throws IOException

Called to indicate that an error occurred on the underlying stream.

Parameters:

exception - the exception to throw

Throws:

IOException - if an I/O error occurs.

finished

public void finished()
              throws IOException

Called to indicate that EOF has been seen on the underlying stream. This method may be called multiple times, if the reader keeps invoking either of the read methods, and they will consequently keep returning EOF.

Throws:

IOException - if an I/O error occurs.