Module java.desktop

Package javax.imageio.stream

Class FileCacheImageInputStream

java.lang.Object

javax.imageio.stream.ImageInputStreamImpl

javax.imageio.stream.FileCacheImageInputStream

All Implemented Interfaces:

Closeable, DataInput, AutoCloseable, ImageInputStream

public class FileCacheImageInputStream
extends ImageInputStreamImpl

An implementation of ImageInputStream that gets its input from a regular InputStream. A file is used to cache previously read data.

Field Summary

Fields declared in class javax.imageio.stream.ImageInputStreamImpl

bitOffset, byteOrder, flushedPos, streamPos

Constructor Summary

Constructors

Constructor	Description
FileCacheImageInputStream(InputStream stream, File cacheDir)	Constructs a FileCacheImageInputStream that will read from a given InputStream.

Method Summary

Modifier and Type	Method	Description
void	close()	Closes this FileCacheImageInputStream, closing and removing the cache file.
protected void	finalize()	Deprecated. The finalize method has been deprecated.
boolean	isCached()	Returns true since this ImageInputStream caches data in order to allow seeking backwards.
boolean	isCachedFile()	Returns true since this ImageInputStream maintains a file cache.
boolean	isCachedMemory()	Returns false since this ImageInputStream does not maintain a main memory cache.
int	read()	Reads a single byte from the stream and returns it as an int between 0 and 255.
int	read(byte[] b, int off, int len)	Reads up to len bytes from the stream, and stores them into b starting at index off.

Methods declared in class javax.imageio.stream.ImageInputStreamImpl

checkClosed, flush, flushBefore, getBitOffset, getByteOrder, getFlushedPosition, getStreamPosition, length, mark, 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, seek, setBitOffset, setByteOrder, skipBytes, skipBytes

Methods declared in class java.lang.Object

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

Constructor Details

FileCacheImageInputStream

public FileCacheImageInputStream(InputStream stream,
 File cacheDir)
                          throws IOException

Constructs a FileCacheImageInputStream that will read from a given InputStream.

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 - an InputStream to read from.

cacheDir - a File indicating where the cache file should be created, or null to use the system directory.

Throws:

IllegalArgumentException - if stream is null.

IllegalArgumentException - if cacheDir is non-null but is not a directory.

IOException - if a cache file cannot be created.

Method Details

read

public int read()
         throws IOException

Description copied from class: ImageInputStreamImpl

Reads a single byte from the stream and returns it as an int between 0 and 255. If EOF is reached, -1 is returned.

Subclasses must provide an implementation for this method. The subclass implementation should update the stream position before exiting.

The bit offset within the stream must be reset to zero before the read occurs.

Specified by:

read in interface