Class FileCacheImageOutputStream
- java.lang.Object
-
- javax.imageio.stream.ImageInputStreamImpl
-
- javax.imageio.stream.ImageOutputStreamImpl
-
- javax.imageio.stream.FileCacheImageOutputStream
- All Implemented Interfaces:
-
Closeable
,DataInput
,DataOutput
,AutoCloseable
,ImageInputStream
,ImageOutputStream
public class FileCacheImageOutputStream extends ImageOutputStreamImpl
An implementation of ImageOutputStream
that writes its output to a regular OutputStream
. A file is used to cache data until it is flushed to the output stream.
Field Summary
Fields declared in class javax.imageio.stream.ImageInputStreamImpl
bitOffset, byteOrder, flushedPos, streamPos
Constructor Summary
Constructor | Description |
---|---|
FileCacheImageOutputStream(OutputStream stream,
File cacheDir) | Constructs a |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
void | close() | Closes this |
boolean | isCached() | Returns |
boolean | isCachedFile() | Returns |
boolean | isCachedMemory() | Returns |
void | seek(long pos) | Sets the current stream position and resets the bit offset to 0. |
Methods declared in class javax.imageio.stream.ImageOutputStreamImpl
flushBits
Methods declared in class javax.imageio.stream.ImageInputStreamImpl
checkClosed, finalize, length, mark, read, read, read, reset, skipBytes, skipBytes
Methods declared in class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Methods declared in interface javax.imageio.stream.ImageInputStream
flush, getBitOffset, getByteOrder, getFlushedPosition, getStreamPosition, length, mark, read, read, read, readBit, readBits, readBoolean, readByte, readBytes, readChar, readDouble, readFloat, readFully, readFully, readFully, readFully, readFully, readFully, readFully, readFully, readInt, readLine, readLong, readShort, readUnsignedByte, readUnsignedInt, readUnsignedShort, readUTF, reset, setBitOffset, setByteOrder, skipBytes, skipBytes
Methods declared in interface javax.imageio.stream.ImageOutputStream
flushBefore, write, write, write, writeBit, writeBits, writeBoolean, writeByte, writeBytes, writeChar, writeChars, writeChars, writeDouble, writeDoubles, writeFloat, writeFloats, writeInt, writeInts, writeLong, writeLongs, writeShort, writeShorts, writeUTF
Constructor Detail
FileCacheImageOutputStream
public FileCacheImageOutputStream(OutputStream stream, File cacheDir) throws IOException
Constructs a FileCacheImageOutputStream
that will write to a given outputStream
.
A temporary file is used as a cache. If cacheDir
is non-null
and is a directory, the file will be created there. If it is null
, the system-dependent default temporary-file directory will be used (see the documentation for File.createTempFile
for details).
- Parameters:
-
stream
- anOutputStream
to write to. -
cacheDir
- aFile
indicating where the cache file should be created, ornull
to use the system directory. - Throws:
-
IllegalArgumentException
- ifstream
isnull
. -
IllegalArgumentException
- ifcacheDir
is non-null
but is not a directory. -
IOException
- if a cache file cannot be created.
Method Detail
seek
public void seek(long pos) throws IOException
Sets the current stream position and resets the bit offset to 0. It is legal to seek past the end of the file; an EOFException
will be thrown only if a read is performed. The file length will not be increased until a write is performed.
- Parameters:
-
pos
- along
containing the desired file pointer position. - Throws:
-
IndexOutOfBoundsException
- ifpos
is smaller than the flushed position. -
IOException
- if any other I/O error occurs.
isCached
public boolean isCached()
Returns true
since this ImageOutputStream
caches data in order to allow seeking backwards.
- Specified by:
-
isCached
in interfaceImageInputStream
- Overrides:
-
isCached
in classImageInputStreamImpl
- Returns:
-
true
. - See Also:
-
isCachedMemory()
,isCachedFile()
isCachedFile
public boolean isCachedFile()
Returns true
since this ImageOutputStream
maintains a file cache.
- Specified by:
-
isCachedFile
in interfaceImageInputStream
- Overrides:
-
isCachedFile
in classImageInputStreamImpl
- Returns:
-
true
. - See Also:
-
isCached()
,isCachedMemory()
isCachedMemory
public boolean isCachedMemory()
Returns false
since this ImageOutputStream
does not maintain a main memory cache.
- Specified by:
-
isCachedMemory
in interfaceImageInputStream
- Overrides:
-
isCachedMemory
in classImageInputStreamImpl
- Returns:
-
false
. - See Also:
-
isCached()
,isCachedFile()
close
public void close() throws IOException
Closes this FileCacheImageOutputStream
. All pending data is flushed to the output, and the cache file is closed and removed. The destination OutputStream
is not closed.
- Throws:
-
IOException
- if an error occurs.