Package org.dellroad.stuff.io

Class IdleTimeoutInputStream

java.lang.Object

java.io.InputStream

org.dellroad.stuff.io.IdleTimeoutInputStream

All Implemented Interfaces:

Closeable, AutoCloseable, AsyncInputStream.Listener

public class IdleTimeoutInputStream
extends InputStream
implements AsyncInputStream.Listener

Wraps an InputStream and enforces a maximum time limit on how long any read() operation may block. If the time limit is exceeded, an IdleTimeoutException is thrown.

As a side effect of its design, this class may also be used to artificially inject data, EOF, or exceptions into the InputStream, using the AsyncInputStream.Listener interface methods.

This class may also be used to allow testing the real-time state of an InputStream without actually reading from it, via checkConnection(), which guarantees an immediate exception will be thrown if the underlying InputStream has been closed, reached EOF, or itself thrown an exception.

All methods in this class are thread safe.

Constructor Summary

Constructors

Constructor	Description
IdleTimeoutInputStream(InputStream in, long timeout)	Convenience constructor.
IdleTimeoutInputStream(InputStream in, String threadName, long timeout)	Constructor.

Method Summary

Modifier and Type	Method	Description
int	available()
void	checkConnection()	Check the status of the underlying InputStream.
void	close()
void	handleEOF()	Handle end-of-file detected on the underlying input.
void	handleException(Throwable e)	Handle an exception detected on the underlying input.
void	handleInput(byte[] buf, int off, int len)	Handle new data read from the underlying input.
int	read()
int	read(byte[] buf, int off, int len)

Methods inherited from class java.io.InputStream

mark, markSupported, nullInputStream, read, readAllBytes, readNBytes, readNBytes, reset, skip, skipNBytes, transferTo

Methods inherited from class java.lang.Object

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

Constructor Details

IdleTimeoutInputStream

public IdleTimeoutInputStream(InputStream in,
 String threadName,
 long timeout)

Constructor.

Parameters:

in - input source

threadName - name for the reader thread, or null for default

timeout - maximum input idle time in milliseconds, or zero for infinity

Throws:

IllegalArgumentException - if timeout is negative

IdleTimeoutInputStream

public IdleTimeoutInputStream(InputStream in,
 long timeout)

Convenience constructor. Equivalent to:

IdleTimeoutInputStream(in, null, timeout);

Parameters:

in - input source

timeout - maximum input idle time in milliseconds, or zero for infinity

Throws:

IllegalArgumentException - if timeout is negative

Method Details

read

public int read()
         throws IOException

Specified by:

read in class InputStream

Throws:

IOException

read

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

Overrides:

read in class InputStream

Throws:

IOException

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class InputStream

available

public int available()
              throws IOException

Overrides:

available in class InputStream

Throws:

IOException

checkConnection

public void checkConnection()
                     throws IOException

Check the status of the underlying InputStream.

This method guarantees that if the underlying InputStream has been closed, reached EOF, or thrown an exception, then this method will throw an immediate exception.

Throws:

EOFException - if the underlying InputStream has reached EOF

IOException - if the underlying InputStream threw an IOException

IOException - if the underlying InputStream has been closed

handleInput

public void handleInput(byte[] buf,
 int off,
 int len)

Description copied from interface: AsyncInputStream.Listener

Handle new data read from the underlying input. This method must not write to buffer bytes outside of the defined region.

Specified by:

handleInput in interface AsyncInputStream.Listener

Parameters:

buf - data buffer

off - starting offset of data in buffer

len - number of bytes of data

handleEOF

public void handleEOF()

Description copied from interface: AsyncInputStream.Listener

Handle end-of-file detected on the underlying input. No further events will be delivered.

Typically the assocaited AsyncInputStream will be closed in this callback.

Specified by:

handleEOF in interface AsyncInputStream.Listener

handleException

public void handleException(Throwable e)

Description copied from interface: AsyncInputStream.Listener

Handle an exception detected on the underlying input. No further events will be delivered.

Typically the assocaited AsyncInputStream will be closed in this callback.

Specified by:

handleException in interface AsyncInputStream.Listener

Parameters:

e - the exception received (usually IOException but could also be any other RuntimeException)