Class RandomAccessSourceFactory

java.lang.Object

com.itextpdf.io.source.RandomAccessSourceFactory

public final class RandomAccessSourceFactory
extends Object

Factory to create IRandomAccessSource objects based on various types of sources

Field Summary

Fields

Modifier and Type	Field	Description
private boolean	exclusivelyLockFile	Whether the underlying file should have a RW lock on it or just an R lock
private boolean	forceRead	Whether the full content of the source should be read into memory at construction
private static boolean	forceReadDefaultValue	The default value for the forceRead flag
private boolean	usePlainRandomAccess	Whether RandomAccessFile should be used instead of a FileChannel, where applicable

Constructor Summary

Constructors

Constructor	Description
RandomAccessSourceFactory()	Creates a factory that will give preference to accessing the underling data source using memory mapped files

Method Summary

Modifier and Type	Method	Description
IRandomAccessSource	createBestSource(String filename)	Creates a IRandomAccessSource based on a filename string.
IRandomAccessSource	createBestSource(FileChannel channel)	Creates a IRandomAccessSource based on memory mapping a file channel.
private IRandomAccessSource	createByReadingToMemory(InputStream stream)	Creates a new IRandomAccessSource by reading the specified file/resource into memory
private IRandomAccessSource	createByReadingToMemory(String filename)	Creates a new IRandomAccessSource by reading the specified file/resource into memory
IRandomAccessSource	createRanged(IRandomAccessSource source, long[] ranges)
IRandomAccessSource	createSource(byte[] data)	Creates a IRandomAccessSource based on a byte array
IRandomAccessSource	createSource(InputStream inputStream)	Creates a IRandomAccessSource based on an InputStream.
IRandomAccessSource	createSource(RandomAccessFile raf)
IRandomAccessSource	createSource(URL url)	Creates a IRandomAccessSource based on a URL.
private static boolean	exceptionIsMapFailureException(IOException e)	Utility method that determines whether a given java.io.IOException is the result of a failure to map a memory mapped file.
IRandomAccessSource	extractOrCreateSource(InputStream inputStream)	Creates or extracts a IRandomAccessSource based on an InputStream.
RandomAccessSourceFactory	setExclusivelyLockFile(boolean exclusivelyLockFile)
RandomAccessSourceFactory	setForceRead(boolean forceRead)	Determines whether the full content of the source will be read into memory
static void	setForceReadDefaultValue(boolean forceRead)	Determines the default value for the forceRead flag
RandomAccessSourceFactory	setUsePlainRandomAccess(boolean usePlainRandomAccess)	Determines whether RandomAccessFile should be used as the primary data access mechanism

Methods inherited from class Object

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

Field Details

forceReadDefaultValue

private static boolean forceReadDefaultValue

The default value for the forceRead flag

forceRead

private boolean forceRead

Whether the full content of the source should be read into memory at construction

usePlainRandomAccess

private boolean usePlainRandomAccess

Whether RandomAccessFile should be used instead of a FileChannel, where applicable

exclusivelyLockFile

private boolean exclusivelyLockFile

Whether the underlying file should have a RW lock on it or just an R lock

Constructor Details

RandomAccessSourceFactory

public RandomAccessSourceFactory()

Creates a factory that will give preference to accessing the underling data source using memory mapped files

Method Details

setForceReadDefaultValue

public static void setForceReadDefaultValue(boolean forceRead)

Determines the default value for the forceRead flag

Parameters:

forceRead - true if by default the full content will be read, false otherwise

setForceRead

public RandomAccessSourceFactory setForceRead(boolean forceRead)

Determines whether the full content of the source will be read into memory

Parameters:

forceRead - true if the full content will be read, false otherwise

Returns:

this object (this allows chaining of method calls)

setUsePlainRandomAccess

public RandomAccessSourceFactory setUsePlainRandomAccess(boolean usePlainRandomAccess)

Determines whether RandomAccessFile should be used as the primary data access mechanism

Parameters:

usePlainRandomAccess - whether RandomAccessFile should be used as the primary data access mechanism

Returns:

this object (this allows chaining of method calls)

setExclusivelyLockFile

public RandomAccessSourceFactory setExclusivelyLockFile(boolean exclusivelyLockFile)

createSource

public IRandomAccessSource createSource(byte[] data)

Creates a IRandomAccessSource based on a byte array

Parameters:

data - the byte array

Returns:

the newly created IRandomAccessSource

createSource

public IRandomAccessSource createSource(RandomAccessFile raf)
                                 throws IOException

Throws:

IOException

createSource

public IRandomAccessSource createSource(URL url)
                                 throws IOException

Creates a IRandomAccessSource based on a URL. The data available at the URL is read into memory and used as the source for the IRandomAccessSource

Parameters:

url - the url to read from

Returns:

the newly created IRandomAccessSource

Throws:

IOException - in case of any I/O error.

extractOrCreateSource

public IRandomAccessSource extractOrCreateSource(InputStream inputStream)
                                          throws IOException

Creates or extracts a IRandomAccessSource based on an InputStream.

If the InputStream is an instance of RASInputStream then extracts the source from it. Otherwise The full content of the InputStream is read into memory and used as the source for the IRandomAccessSource

Parameters:

inputStream - the stream to read from

Returns:

the newly created or extracted IRandomAccessSource

Throws:

IOException - in case of any I/O error.

createSource

public IRandomAccessSource createSource(InputStream inputStream)
                                 throws IOException

Creates a IRandomAccessSource based on an InputStream.

The full content of the InputStream is read into memory and used as the source for the IRandomAccessSource

Parameters:

inputStream - the stream to read from

Returns:

the newly created IRandomAccessSource

Throws:

IOException - in case of any I/O error.

createBestSource

public IRandomAccessSource createBestSource(String filename)
                                     throws IOException

Creates a IRandomAccessSource based on a filename string. If the filename describes a URL, a URL based source is created If the filename describes a file on disk, the contents may be read into memory (if forceRead is true), opened using memory mapped file channel (if usePlainRandomAccess is false), or opened using RandomAccessFile access (if usePlainRandomAccess is true) This call will automatically fail over to using RandomAccessFile if the memory map operation fails

Parameters:

filename - the name of the file or resource to create the IRandomAccessSource for

Returns:

the newly created IRandomAccessSource

Throws:

IOException - in case of any I/O error

createBestSource

public IRandomAccessSource createBestSource(FileChannel channel)
                                     throws IOException

Creates a IRandomAccessSource based on memory mapping a file channel. Unless you are explicitly working with a FileChannel already, it is better to use createBestSource(String). If the file is large, it will be opened using a paging strategy.

Parameters:

channel - the name of the file or resource to create the IRandomAccessSource for

Returns:

the newly created IRandomAccessSource

Throws:

IOException - in case of any I/O error

createRanged

public IRandomAccessSource createRanged(IRandomAccessSource source,
 long[] ranges)
                                 throws IOException

Throws:

IOException

createByReadingToMemory

private IRandomAccessSource createByReadingToMemory(String filename)
                                             throws IOException

Creates a new IRandomAccessSource by reading the specified file/resource into memory

Parameters:

filename - the name of the resource to read

Returns:

the newly created IRandomAccessSource

Throws:

IOException - if reading the underling file or stream fails

createByReadingToMemory

private IRandomAccessSource createByReadingToMemory(InputStream stream)
                                             throws IOException

Creates a new IRandomAccessSource by reading the specified file/resource into memory

Parameters:

stream - the name of the resource to read

Returns:

the newly created IRandomAccessSource

Throws:

IOException - if reading the underling file or stream fails

exceptionIsMapFailureException

private static boolean exceptionIsMapFailureException(IOException e)

Utility method that determines whether a given java.io.IOException is the result of a failure to map a memory mapped file. It would be better if the runtime provided a special exception for this case, but it doesn't, so we have to rely on parsing the exception message.

Parameters:

e - the exception to check

Returns:

true if the exception was the result of a failure to map a memory mapped file