Package com.levigo.jadice.document.io

Class IOUtils

java.lang.Object

com.levigo.jadice.document.io.IOUtils

public final class IOUtils
extends Object

Field Summary

Fields

Modifier and Type	Field	Description
static int	COPY_CHUNK_SIZE
static int	DEFAULT_BUFFER_SIZE

Method Summary

Modifier and Type	Method	Description
static long	copy(InputStream in, OutputStream out)
static long	copy(InputStream in, OutputStream out, int bufferSize)
static void	copyAndClose(InputStream is, OutputStream os)	Copies all data from input to output.
static void	copyStream(SeekableInputStream is, ImageOutputStream os)
static void	deleteAllBelow(File file)	Recursively delete everything below a given directory, but don't remove the directory itself.
static void	deleteRecursively(File file)	Recursively delete a file or directory.
static long	determineLength(SeekableInputStream is)	Determines and returns the stream length either by checking whether the stream returns a reasonable length (some instances may not be able to do that) or just reading over it, until an EOF is hit.
static void	discardStream(InputStream is)	Copies all data from the input stream.
static void	drainAsynchronously(InputStream is)	Eagerly drain the given input stream.
static void	drainSynchronously(InputStream is)	Eagerly drain the given input stream.
static long	forcedDetermineLength(SeekableInputStream is)	Determines and returns the stream length by reading over the complete stream until an EOF was found.
static boolean	isBufferManagerActive()	Checks if BufferManager is available and enabled
static boolean	isTryFileCaching()	Return whether to try to cache data in local files by default.
static void	setTryFileCaching(boolean tryFileCaching)	Set whether to try to cache data in local files by default.
static SeekableInputStream	wrap(InputStream is)	Wraps the given stream into a SeekableInputStream.
static SeekableInputStream	wrap(InputStream inputStream, boolean tryLocalTmpFileAccess)	Wraps the given stream into SeekableInputStream.
static SeekableInputStream	wrap(InputStream inputStream, boolean tryLocalTmpFileAccess, boolean ignoreSeekableStream)	Wraps the given stream into SeekableInputStream.
static SeekableInputStream	wrap(ImageInputStream imageInputStream)	Wraps the given ImageInputStream into an SeekableInputStream.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_BUFFER_SIZE

public static final int DEFAULT_BUFFER_SIZE

See Also:

Constant Field Values

COPY_CHUNK_SIZE

public static final int COPY_CHUNK_SIZE

See Also:

Constant Field Values

Method Detail

copy

public static long copy(InputStream in,
                        OutputStream out)
                 throws IOException

Throws:

IOException

copy

public static long copy(InputStream in,
                        OutputStream out,
                        int bufferSize)
                 throws IOException

Throws:

IOException

copyAndClose

public static void copyAndClose(InputStream is,
                                OutputStream os)
                         throws IOException

Copies all data from input to output. Closes the streams afterwards.

Throws:

IOException

discardStream

public static void discardStream(InputStream is)
                          throws IOException

Copies all data from the input stream. Does NOT close the input stream.

Throws:

IOException

deleteRecursively

public static void deleteRecursively(File file)

Recursively delete a file or directory.

deleteAllBelow

public static void deleteAllBelow(File file)

Recursively delete everything below a given directory, but don't remove the directory itself.

copyStream

public static void copyStream(SeekableInputStream is,
                              ImageOutputStream os)
                       throws IOException

Throws:

IOException

determineLength

public static long determineLength(SeekableInputStream is)
                            throws IOException

Determines and returns the stream length either by checking whether the stream returns a reasonable length (some instances may not be able to do that) or just reading over it, until an EOF is hit. Users of given stream need to deal with synchronization against other users of the same stream instance.

Parameters:

is - the stream to determine its length

Returns:

the length, the length returned by SeekableInputStream.length() if positive, or the length of the stream determined by reading over it. the length is measured in bytes.

Throws:

IOException - if an I/O error occurs.

forcedDetermineLength

public static long forcedDetermineLength(SeekableInputStream is)
                                  throws IOException

Determines and returns the stream length by reading over the complete stream until an EOF was found.

Note: Users of given stream need to deal with synchronization against other users of the same stream instance.

Parameters:

is - the stream to determine its length

Returns:

the length of the stream determined by reading over it. The length is measured in bytes.

Throws:

IOException - if an I/O error occurs.

drainSynchronously

public static void drainSynchronously(InputStream is)

Eagerly drain the given input stream. This method will block until all data has been read and the stream's EOF has been reached.

drainAsynchronously

public static void drainAsynchronously(InputStream is)

Eagerly drain the given input stream. Draining will be performed in the background. This method will synchronize on the InputStream while doing block-wise reads.

wrap

public static final SeekableInputStream wrap(InputStream is)
                                      throws IOException

Wraps the given stream into a SeekableInputStream. Checks the given input stream and if necessary wraps it with an appropriate SeekableInputStream implementation. This method will try to buffer all data into a temporary file if possible. If additionally a BufferManager is available on the classpath and temporary buffering is possible, the buffering of data will be handled by the BufferManager. If temporary buffering is not possible (e.g. due to security restrictions), all data will be buffered in memory.

Parameters:

is - the stream to wrap

Returns:

a SeekableInputStream instance wrapping the original InputStream

Throws:

IOException - if an i/o error occurred

IllegalArgumentException - if the given InputStream is null

wrap

public static final SeekableInputStream wrap(InputStream inputStream,
                                             boolean tryLocalTmpFileAccess)
                                      throws IOException

Wraps the given stream into SeekableInputStream. Checks the given input stream and if necessary wraps it with an appropriate SeekableInputStream, which is returned. If tryLocalTmpFileAccess is true, this method will try to buffer all data into a temporary file if possible. If additionally a BufferManager is available on the classpath and temporary buffering is possible, the buffering of data will be handled by the BufferManager. If temporary buffering is not possible (e.g. due to security restrictions), all data will be buffered in memory.

Parameters:

inputStream - the stream to wrap

tryLocalTmpFileAccess - enable/disable temporary file data buffering.

Returns:

a SeekableInputStream instance wrapping the original InputStream

Throws:

IOException - if an i/o error occurred

IllegalArgumentException - if the given InputStream is null

wrap

public static final SeekableInputStream wrap(InputStream inputStream,
                                             boolean tryLocalTmpFileAccess,
                                             boolean ignoreSeekableStream)
                                      throws IOException

Wraps the given stream into SeekableInputStream. Checks the given input stream and if necessary wraps it with an appropriate SeekableInputStream, which is returned. If tryLocalTmpFileAccess is true, this method will try to buffer all data into a temporary file if possible. If additionally a BufferManager is available on the classpath and temporary buffering is possible, the buffering of data will be handled by the BufferManager. If temporary buffering is not possible (e.g. due to security restrictions), all data will be buffered in memory.

Parameters:

inputStream - the stream to wrap

tryLocalTmpFileAccess - enable/disable temporary file data buffering.

ignoreSeekableStream - if the given inputStream is already an instance of SeekableInputStream it will be ignored and not wrapped any further if this flag is set to true

Returns:

a SeekableInputStream instance wrapping the original InputStream

Throws:

IOException - if an i/o error occurred

IllegalArgumentException - if the given InputStream is null

wrap

public static SeekableInputStream wrap(ImageInputStream imageInputStream)

Wraps the given ImageInputStream into an SeekableInputStream. If the provided ImageInputStream is already an implementation of SeekableInputStream, it will not be wrapped and the original instance will be returned. If the ImageInputStream is not an instance of SeekableInputStream, a lightweight delegation implementation will be created and returned.

Parameters:

imageInputStream - the ImageInputStream to wrap

Returns:

a SeekableInputStream instance

Throws:

IllegalArgumentException - if the provided ImageInputStream is null.

setTryFileCaching

public static void setTryFileCaching(boolean tryFileCaching)

Set whether to try to cache data in local files by default. This value is used by wrap(InputStream).

Parameters:

tryFileCaching - true if local file caching should be tried by default

isTryFileCaching

public static boolean isTryFileCaching()

Return whether to try to cache data in local files by default.

Returns:

true if local file caching is tried by default

isBufferManagerActive

public static boolean isBufferManagerActive()

Checks if BufferManager is available and enabled

Returns:

true if BufferManager is available and enabled