Package org.apache.pdfbox.io

Class IOUtils

java.lang.Object

org.apache.pdfbox.io.IOUtils

public final class IOUtils
extends Object

This class contains various I/O-related methods.

Field Summary

Fields

Modifier and Type	Field	Description
private static final org.apache.commons.logging.Log	LOG	Log instance.
private static final RandomAccessStreamCache.StreamCacheCreateFunction	streamCache
private static final Optional<Consumer<ByteBuffer>>	UNMAPPER

Constructor Summary

Constructors

Modifier	Constructor	Description
private	IOUtils()

Method Summary

Modifier and Type	Method	Description
static IOException	closeAndLogException(Closeable closeable, org.apache.commons.logging.Log logger, String resourceName, IOException initialException)	Try to close an IO resource and log and return if there was an exception.
static void	closeQuietly(Closeable closeable)	Null safe close of the given Closeable suppressing any exception.
static long	copy(InputStream input, OutputStream output)	Copies all the contents from the given input stream to the given output stream.
static RandomAccessStreamCache.StreamCacheCreateFunction	createMemoryOnlyStreamCache()	Provides a function to create an instance of a memory only StreamCache using unrestricted main memory.
static RandomAccessStreamCache.StreamCacheCreateFunction	createTempFileOnlyStreamCache()	Provides a function to create an instance of a temp file only StreamCache using unrestricted size.
private static Consumer<ByteBuffer>	newBufferCleaner(Class<?> unmappableBufferClass, MethodHandle unmapper)
static long	populateBuffer(InputStream in, byte[] buffer)	Populates the given buffer with data read from the input stream.
static byte[]	toByteArray(InputStream in)	Reads the input stream and returns its contents as a byte array.
static void	unmap(ByteBuffer buf)	Unmap memory mapped byte buffers.
private static Consumer<ByteBuffer>	unmapper()	This is adapted from org.apache.lucene.store.MMapDirectory

Methods inherited from class java.lang.Object

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

Field Details

LOG

private static final org.apache.commons.logging.Log LOG

Log instance.

streamCache

private static final RandomAccessStreamCache.StreamCacheCreateFunction streamCache

UNMAPPER

private static final Optional<Consumer<ByteBuffer>> UNMAPPER

Constructor Details

IOUtils

private IOUtils()

Method Details

toByteArray

public static byte[] toByteArray(InputStream in)
                          throws IOException

Reads the input stream and returns its contents as a byte array.

Parameters:

in - the input stream to read from.

Returns:

the byte array

Throws:

IOException - if an I/O error occurs

copy

public static long copy(InputStream input,
 OutputStream output)
                 throws IOException

Copies all the contents from the given input stream to the given output stream.

Parameters:

input - the input stream

output - the output stream

Returns:

the number of bytes that have been copied

Throws:

IOException - if an I/O error occurs

populateBuffer

public static long populateBuffer(InputStream in,
 byte[] buffer)
                           throws IOException

Populates the given buffer with data read from the input stream. If the data doesn't fit the buffer, only the data that fits in the buffer is read. If the data is less than fits in the buffer, the buffer is not completely filled.

Parameters:

in - the input stream to read from

buffer - the buffer to fill

Returns:

the number of bytes written to the buffer

Throws:

IOException - if an I/O error occurs

closeQuietly

public static void closeQuietly(Closeable closeable)

Null safe close of the given Closeable suppressing any exception.

Parameters:

closeable - to be closed

closeAndLogException

public static IOException closeAndLogException(Closeable closeable,
 org.apache.commons.logging.Log logger,
 String resourceName,
 IOException initialException)

Try to close an IO resource and log and return if there was an exception.

An exception is only returned if the IOException passed in is null.

Parameters:

closeable - to be closed

logger - the logger to be used so that logging appears under that log instance

resourceName - the name to appear in the log output

initialException - if set, this exception will be returned even where there is another exception while closing the IO resource

Returns:

the IOException is there was any but only if initialException is null

unmap

public static void unmap(ByteBuffer buf)

Unmap memory mapped byte buffers. This is a hack waiting for a proper JVM provided solution expected in java 10 https://bugs.openjdk.java.net/browse/JDK-4724038 The issue here is that even when closed, memory mapped byte buffers hold a lock on the underlying file until GC is executes and this in turns result in an error if the user tries to move or delete the file.

Parameters:

buf - the buffer to be unmapped

unmapper

private static Consumer<ByteBuffer> unmapper()

This is adapted from org.apache.lucene.store.MMapDirectory

Returns:

newBufferCleaner

private static Consumer<ByteBuffer> newBufferCleaner(Class<?> unmappableBufferClass,
 MethodHandle unmapper)

createMemoryOnlyStreamCache

public static RandomAccessStreamCache.StreamCacheCreateFunction createMemoryOnlyStreamCache()

Provides a function to create an instance of a memory only StreamCache using unrestricted main memory. RandomAccessReadWriteBuffer is used as current default implementation.

Returns:

a function to create an instance of a memory only StreamCache using unrestricted main memory

createTempFileOnlyStreamCache

public static RandomAccessStreamCache.StreamCacheCreateFunction createTempFileOnlyStreamCache()

Provides a function to create an instance of a temp file only StreamCache using unrestricted size. ScratchFile is used as current default implementation.

Returns:

a function to create an instance of a temp file only StreamCache using unrestricted size