org.mule.runtime.api.streaming.bytes

Class ImmutableFileRepeatableInputStream

java.lang.Object

java.io.InputStream

org.mule.runtime.api.streaming.bytes.ImmutableFileRepeatableInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public final class ImmutableFileRepeatableInputStream
extends InputStream

An InputStream implementation that allows obtaining a repeatable stream from the contents of an immutable file that already exists in the local file system.

The Mule Runtime is capable of generating larger than memory repeatable streams by buffering into a temporal file in the local file system. The problem with that approach is that when the contents of the original stream are already present in the file system, the temporary file is still created, consuming unnecessary disk space and IO time.

This class allows to generate an InputStream from a local file that the repeatable streaming engine will buffer from instead of generating a new one.

Immutability is a MANDATORY PRECONDITION for using this class. The file WILL NOT be modified by this class or the Mule streaming framework in any way. But at the same time, the file's immutability needs to be guaranteed, at least for the duration of this stream's lifecycle. This means that while the file is in use by instances of this class, no other process or thread can modify the file's content. Failing to meet this condition will result in dirty reads and content corruption. If this condition cannot be assured, then use a regular FileInputStream instead.

Also keep in mind that the purpose of this class is to optimize repeatable streaming resources on certain cases. However, in the context of a Mule application, the user can always decide to disable repeatable streaming, in which case, this stream will not be treated in a repeatable manner. The user can also configure an in-memory streaming strategy, in which case the behavior will be similar to using a FileInputStream.

Finally, notice that this stream is not auto closeable. close() method needs to be invoked explicitly.

Since:

1.3.0

Constructor Summary

Constructors

Constructor and Description
ImmutableFileRepeatableInputStream(File file, boolean autoDelete) Creates a new instance

Method Summary

Modifier and Type	Method and Description
int	available()
void	close()
File	getFile()
boolean	isAutoDelete()
void	mark(int readlimit)
boolean	markSupported()
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)
void	reset()
long	skip(long n)

Methods inherited from class java.lang.Object

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

Constructor Detail

ImmutableFileRepeatableInputStream

public ImmutableFileRepeatableInputStream(File file,
                                          boolean autoDelete)

Creates a new instance

Parameters:

file - the File that contains the stream's contents

autoDelete - if true, the file will be deleted when close() is invoked.

Throws:

IllegalArgumentException - if the file cannot be found

Method Detail

getFile

public File getFile()

Returns:

The File backing this stream

isAutoDelete

public boolean isAutoDelete()

Returns:

Whether the file will be deleted upon close() or not.

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class InputStream

Throws:

IOException

read

public int read()
         throws IOException

Specified by:

read in class InputStream

Throws:

IOException

read

public int read(byte[] b)
         throws IOException

Overrides:

read in class InputStream

Throws:

IOException

read

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

Overrides:

read in class InputStream

Throws:

IOException

skip

public long skip(long n)
          throws IOException

Overrides:

skip in class InputStream

Throws:

IOException

available

public int available()
              throws IOException

Overrides:

available in class InputStream

Throws:

IOException

mark

public void mark(int readlimit)

Overrides:

mark in class InputStream

reset

public void reset()
           throws IOException

Overrides:

reset in class InputStream

Throws:

IOException

markSupported

public boolean markSupported()

Overrides:

markSupported in class InputStream