Package org.cyclos.server.utils

Class SerializableInputStream

java.lang.Object

java.io.InputStream

org.cyclos.server.utils.SerializableInputStream

All Implemented Interfaces:

Closeable, Serializable, AutoCloseable

public class SerializableInputStream
extends InputStream
implements Serializable

An InputStream which wraps another InputStream, so that intra-jvm access is done directly on that stream. However, when it's serialized, the data is sent on chunks and, when read on the other side, those chunks are written in a temporary file. So, it's safe to serialize large amount of data without consuming large memory.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
SerializableInputStream(byte[] bytes)	Shortcut to SerializableInputStream(InputStream) using a ByteArrayInputStream
SerializableInputStream(File file)	Reads the given file, deleting it when close() is invoked
SerializableInputStream(InputStream inputStream)	Wraps the given stream
SerializableInputStream(Blob blob)	Wraps the given blob, and calls forceCopyToFile(), as blobs can only be accessed from within a database transaction

Method Summary

Modifier and Type	Method	Description
void	close()
File	file()	Returns a temporary File with the contents of this stream.
File	forceCopyToFile()	Exhausts the open stream and copy the contents to a temporary file.
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)
void	reOpen()	Closes the underlying stream and opens a new one from file to start reading from

Methods inherited from class java.io.InputStream

available, mark, markSupported, nullInputStream, readAllBytes, readNBytes, readNBytes, reset, skip, transferTo

Methods inherited from class java.lang.Object

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

Constructor Detail

SerializableInputStream

public SerializableInputStream(Blob blob)
                        throws IOException

Wraps the given blob, and calls forceCopyToFile(), as blobs can only be accessed from within a database transaction

Throws:

IOException

SerializableInputStream

public SerializableInputStream(byte[] bytes)

Shortcut to SerializableInputStream(InputStream) using a ByteArrayInputStream

SerializableInputStream

public SerializableInputStream(File file)

Reads the given file, deleting it when close() is invoked

SerializableInputStream

public SerializableInputStream(InputStream inputStream)

Wraps the given stream

Method Detail

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class InputStream

Throws:

IOException

file

public File file()
          throws IOException,
                 IllegalStateException

Returns a temporary File with the contents of this stream. When the stream has been serialized, the contents is already on a temporary file, so it is returned. Otherwise, copy the wrapped stream into a temporary file and return it. It is important to state that after this method is invoked, the temporary file will no longer be deleted when this stream is closed, and it's the callers responsibility to remove the temporary file.

Throws:

IOException - When there was an error reading to the temporary file

IllegalStateException - When this stream was already closed

forceCopyToFile

public File forceCopyToFile()
                     throws IOException

Exhausts the open stream and copy the contents to a temporary file. No-op if already on a file. The file is not marked as to being kept (opposed to what happens on the file() method), so, subsequent invocation of close() method will delete the file

Throws:

IOException - Error writing to file

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

reOpen

public void reOpen()
            throws IOException

Closes the underlying stream and opens a new one from file to start reading from

Throws:

IOException - if the file is missing