@Beta public final class FileBackedOutputStream extends java.io.OutputStream
OutputStream
that starts buffering to a byte array, but
switches to file buffering once the data reaches a configurable size.
This class is thread-safe.
Modifier and Type | Class and Description |
---|---|
private static class |
FileBackedOutputStream.MemoryOutput
ByteArrayOutputStream that exposes its internals.
|
Modifier and Type | Field and Description |
---|---|
private java.io.File |
file |
private int |
fileThreshold |
private FileBackedOutputStream.MemoryOutput |
memory |
private java.io.OutputStream |
out |
private boolean |
resetOnFinalize |
private ByteSource |
source |
Constructor and Description |
---|
FileBackedOutputStream(int fileThreshold)
Creates a new instance that uses the given file threshold, and does
not reset the data when the
ByteSource returned by
asByteSource() is finalized. |
FileBackedOutputStream(int fileThreshold,
boolean resetOnFinalize)
Creates a new instance that uses the given file threshold, and
optionally resets the data when the
ByteSource returned
by asByteSource() is finalized. |
Modifier and Type | Method and Description |
---|---|
ByteSource |
asByteSource()
Returns a readable
ByteSource view of the data that has been
written to this stream. |
void |
close() |
void |
flush() |
(package private) java.io.File |
getFile()
Returns the file holding the data (possibly null).
|
private java.io.InputStream |
openInputStream() |
void |
reset()
Calls
close() if not already closed, and then resets this
object back to its initial state, for reuse. |
private void |
update(int len)
Checks if writing
len bytes would go over threshold, and
switches to file buffering if so. |
void |
write(byte[] b) |
void |
write(byte[] b,
int off,
int len) |
void |
write(int b) |
private final int fileThreshold
private final boolean resetOnFinalize
private final ByteSource source
private java.io.OutputStream out
private FileBackedOutputStream.MemoryOutput memory
private java.io.File file
public FileBackedOutputStream(int fileThreshold)
ByteSource
returned by
asByteSource()
is finalized.fileThreshold
- the number of bytes before the stream should
switch to buffering to a filepublic FileBackedOutputStream(int fileThreshold, boolean resetOnFinalize)
ByteSource
returned
by asByteSource()
is finalized.fileThreshold
- the number of bytes before the stream should
switch to buffering to a fileresetOnFinalize
- if true, the reset()
method will
be called when the ByteSource
returned by asByteSource()
is finalizedjava.io.File getFile()
public ByteSource asByteSource()
ByteSource
view of the data that has been
written to this stream.private java.io.InputStream openInputStream() throws java.io.IOException
java.io.IOException
public void reset() throws java.io.IOException
close()
if not already closed, and then resets this
object back to its initial state, for reuse. If data was buffered
to a file, it will be deleted.java.io.IOException
- if an I/O error occurred while deleting the file bufferpublic void write(int b) throws java.io.IOException
write
in class java.io.OutputStream
java.io.IOException
public void write(byte[] b) throws java.io.IOException
write
in class java.io.OutputStream
java.io.IOException
public void write(byte[] b, int off, int len) throws java.io.IOException
write
in class java.io.OutputStream
java.io.IOException
public void close() throws java.io.IOException
close
in interface java.io.Closeable
close
in interface java.lang.AutoCloseable
close
in class java.io.OutputStream
java.io.IOException
public void flush() throws java.io.IOException
flush
in interface java.io.Flushable
flush
in class java.io.OutputStream
java.io.IOException
private void update(int len) throws java.io.IOException
len
bytes would go over threshold, and
switches to file buffering if so.java.io.IOException