org.eclipse.jgit.util

Class TemporaryBuffer

java.lang.Object

java.io.OutputStream

org.eclipse.jgit.util.TemporaryBuffer

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

Direct Known Subclasses:

TemporaryBuffer.Heap, TemporaryBuffer.LocalFile

public abstract class TemporaryBuffer
extends OutputStream

A fully buffered output stream.

Subclasses determine the behavior when the in-memory buffer capacity has been exceeded and additional bytes are still being received for output.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	TemporaryBuffer.Heap A temporary buffer that will never exceed its in-memory limit.
static class	TemporaryBuffer.LocalFile A fully buffered output stream using local disk storage for large data.

Field Summary

Fields

Modifier and Type	Field and Description
protected static int	DEFAULT_IN_CORE_LIMIT Default limit for in-core storage.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	TemporaryBuffer(int limit) Create a new empty temporary buffer.
protected	TemporaryBuffer(int estimatedSize, int limit) Create a new empty temporary buffer.

Method Summary

Modifier and Type	Method and Description
void	close()
void	copy(InputStream in) Copy all bytes remaining on the input stream into this buffer.
void	destroy() Clear this buffer so it has no data, and cannot be used again.
protected void	doFlush() Dumps the entire buffer into the overflow stream, and flushes it.
long	length() Obtain the length (in bytes) of the buffer.
InputStream	openInputStream() Open an input stream to read from the buffered data.
protected abstract OutputStream	overflow() Open the overflow output stream, so the remaining output can be stored.
void	reset() Reset this buffer for reuse, purging all buffered content.
byte[]	toByteArray() Convert this buffer's contents into a contiguous byte array.
byte[]	toByteArray(int limit) Convert this buffer's contents into a contiguous byte array.
void	write(byte[] b, int off, int len)
void	write(int b)
void	writeTo(OutputStream os, ProgressMonitor pm) Send this buffer to an output stream.

Methods inherited from class java.io.OutputStream

flush, write

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_IN_CORE_LIMIT

protected static final int DEFAULT_IN_CORE_LIMIT

Default limit for in-core storage.

See Also:

Constant Field Values

Constructor Detail

TemporaryBuffer

protected TemporaryBuffer(int limit)

Create a new empty temporary buffer.

Parameters:

limit - maximum number of bytes to store in memory before entering the overflow output path; also used as the estimated size.

TemporaryBuffer

protected TemporaryBuffer(int estimatedSize,
                          int limit)

Create a new empty temporary buffer.

Parameters:

estimatedSize - estimated size of storage used, to size the initial list of block pointers.

limit - maximum number of bytes to store in memory before entering the overflow output path.

Since:

4.0

Method Detail

write

public void write(int b)
           throws IOException

Specified by:

write in class OutputStream

Throws:

IOException

write

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

Overrides:

write in class OutputStream

Throws:

IOException

doFlush

protected void doFlush()
                throws IOException

Dumps the entire buffer into the overflow stream, and flushes it.

Throws:

IOException - the overflow stream cannot be started, or the buffer contents cannot be written to it, or it failed to flush.

copy

public void copy(InputStream in)
          throws IOException

Copy all bytes remaining on the input stream into this buffer.

Parameters:

in - the stream to read from, until EOF is reached.

Throws:

IOException - an error occurred reading from the input stream, or while writing to a local temporary file.

length

public long length()

Obtain the length (in bytes) of the buffer.

The length is only accurate after close() has been invoked.

Returns:

total length of the buffer, in bytes.

toByteArray

public byte[] toByteArray()
                   throws IOException

Convert this buffer's contents into a contiguous byte array.

The buffer is only complete after close() has been invoked.

Returns:

the complete byte array; length matches length().

Throws:

IOException - an error occurred reading from a local temporary file

toByteArray

public byte[] toByteArray(int limit)
                   throws IOException

Convert this buffer's contents into a contiguous byte array. If this size of the buffer exceeds the limit only return the first limit bytes

The buffer is only complete after close() has been invoked.

Parameters:

limit - the maximum number of bytes to be returned

Returns:

the byte array limited to limit bytes.

Throws:

IOException - an error occurred reading from a local temporary file

Since:

4.2

writeTo

public void writeTo(OutputStream os,
                    ProgressMonitor pm)
             throws IOException

Send this buffer to an output stream.

This method may only be invoked after close() has completed normally, to ensure all data is completely transferred.

Parameters:

os - stream to send this buffer's complete content to.

pm - if not null progress updates are sent here. Caller should initialize the task and the number of work units to length()/1024.

Throws:

IOException - an error occurred reading from a temporary file on the local system, or writing to the output stream.

openInputStream

public InputStream openInputStream()
                            throws IOException

Open an input stream to read from the buffered data.

This method may only be invoked after close() has completed normally, to ensure all data is completely transferred.

Returns:

a stream to read from the buffer. The caller must close the stream when it is no longer useful.

Throws:

IOException - an error occurred opening the temporary file.

reset

public void reset()

Reset this buffer for reuse, purging all buffered content.

overflow

protected abstract OutputStream overflow()
                                  throws IOException

Open the overflow output stream, so the remaining output can be stored.

Returns:

the output stream to receive the buffered content, followed by the remaining output.

Throws:

IOException - the buffer cannot create the overflow stream.

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class OutputStream

Throws:

IOException

destroy

public void destroy()

Clear this buffer so it has no data, and cannot be used again.