org.apache.commons.io.input

Class QueueInputStream

java.lang.Object

java.io.InputStream

org.apache.commons.io.input.QueueInputStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class QueueInputStream
extends java.io.InputStream

Simple alternative to JDK PipedInputStream; queue input stream provides what's written in queue output stream.

To build an instance, see QueueInputStream.Builder.

Example usage:

 QueueInputStream inputStream = new QueueInputStream();
 QueueOutputStream outputStream = inputStream.newQueueOutputStream();

 outputStream.write("hello world".getBytes(UTF_8));
 inputStream.read();
 

Unlike JDK PipedInputStream and PipedOutputStream, queue input/output streams may be used safely in a single thread or multiple threads. Also, unlike JDK classes, no special meaning is attached to initial or current thread. Instances can be used longer after initial threads exited.

Closing a QueueInputStream has no effect. The methods in this class can be called after the stream has been closed without generating an IOException.

Since:

2.9.0

See Also:

QueueOutputStream

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	QueueInputStream.Builder Builds a new QueueInputStream instance.

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.concurrent.BlockingQueue<java.lang.Integer>	blockingQueue
private long	timeoutNanos

Constructor Summary

Constructors

Modifier	Constructor and Description
	QueueInputStream() Constructs a new instance with no limit to its internal queue size and zero timeout.
	QueueInputStream(java.util.concurrent.BlockingQueue<java.lang.Integer> blockingQueue) Deprecated. Use builder(), QueueInputStream.Builder, and QueueInputStream.Builder.get().
private	QueueInputStream(java.util.concurrent.BlockingQueue<java.lang.Integer> blockingQueue, java.time.Duration timeout) Constructs a new instance with given queue and timeout.

Method Summary

Modifier and Type	Method and Description
static QueueInputStream.Builder	builder() Constructs a new QueueInputStream.Builder.
(package private) java.util.concurrent.BlockingQueue<java.lang.Integer>	getBlockingQueue() Gets the blocking queue.
(package private) java.time.Duration	getTimeout() Gets the timeout duration.
QueueOutputStream	newQueueOutputStream() Constructs a new QueueOutputStream instance connected to this.
int	read() Reads and returns a single byte.

Methods inherited from class java.io.InputStream

available, close, mark, markSupported, read, read, reset, skip

Methods inherited from class java.lang.Object

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

Field Detail

blockingQueue

private final java.util.concurrent.BlockingQueue<java.lang.Integer> blockingQueue

timeoutNanos

private final long timeoutNanos

Constructor Detail

QueueInputStream

public QueueInputStream()

Constructs a new instance with no limit to its internal queue size and zero timeout.

QueueInputStream

@Deprecated
public QueueInputStream(java.util.concurrent.BlockingQueue<java.lang.Integer> blockingQueue)

Deprecated. Use builder(), QueueInputStream.Builder, and QueueInputStream.Builder.get().

Constructs a new instance with given queue and zero timeout.

Parameters:

blockingQueue - backing queue for the stream.

QueueInputStream

private QueueInputStream(java.util.concurrent.BlockingQueue<java.lang.Integer> blockingQueue,
                         java.time.Duration timeout)

Constructs a new instance with given queue and timeout.

Parameters:

blockingQueue - backing queue for the stream.

timeout - how long to wait before giving up when polling the queue.

Method Detail

builder

public static QueueInputStream.Builder builder()

Constructs a new QueueInputStream.Builder.

Returns:

a new QueueInputStream.Builder.

Since:

2.12.0

getBlockingQueue

java.util.concurrent.BlockingQueue<java.lang.Integer> getBlockingQueue()

Gets the blocking queue.

Returns:

the blocking queue.

getTimeout

java.time.Duration getTimeout()

Gets the timeout duration.

Returns:

the timeout duration.

newQueueOutputStream

public QueueOutputStream newQueueOutputStream()

Constructs a new QueueOutputStream instance connected to this. Writes to the output stream will be visible to this input stream.

Returns:

QueueOutputStream connected to this stream.

read

public int read()

Reads and returns a single byte.

Specified by:

read in class java.io.InputStream

Returns:

the byte read, or -1 if a timeout occurs before a queue element is available.

Throws:

java.lang.IllegalStateException - if thread is interrupted while waiting.