public class FileImageInputStream extends ImageInputStreamImpl
An implementation of ImageInputStream that gets its input from a File or RandomAccessFile. The file contents are assumed to be stable during the lifetime of the object.
bitOffset, byteOrder, flushedPos, streamPos public FileImageInputStream(File f)
throws FileNotFoundException,
IOException Constructs a FileImageInputStream that will read from a given File.
The file contents must not change between the time this object is constructed and the time of the last call to a read method.
f - a File to read from.IllegalArgumentException - if f is null.SecurityException - if a security manager exists and does not allow read access to the file.FileNotFoundException - if f is a directory or cannot be opened for reading for any other reason.IOException - if an I/O error occurs.public FileImageInputStream(RandomAccessFile raf)
Constructs a FileImageInputStream that will read from a given RandomAccessFile.
The file contents must not change between the time this object is constructed and the time of the last call to a read method.
raf - a RandomAccessFile to read from.IllegalArgumentException - if raf is null.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.
read in interface ImageInputStream
read in class ImageInputStreamImpl
-1 if EOF is reached.IOException - if the stream has been closed.public int read(byte[] b,
int off,
int len)
throws IOException Description copied from class: ImageInputStreamImpl
Reads up to len bytes from the stream, and stores them into b starting at index off. If no bytes can be read because the end of the stream has been reached, -1 is returned.
The bit offset within the stream must be reset to zero before the read occurs.
Subclasses must provide an implementation for this method. The subclass implementation should update the stream position before exiting.
read in interface ImageInputStream
read in class ImageInputStreamImpl
b - an array of bytes to be written to.off - the starting position within b to write to.len - the maximum number of bytes to read.-1 to indicate EOF.IOException - if an I/O error occurs.public long length()
Returns the length of the underlying file, or -1 if it is unknown.
length in interface ImageInputStream
length in class ImageInputStreamImpl
long, or -1.public void seek(long pos)
throws IOException Description copied from interface: ImageInputStream
Sets the current stream position to the desired location. The next read will occur at this location. The bit offset is set to 0.
An IndexOutOfBoundsException will be thrown if pos is smaller than the flushed position (as returned by getflushedPosition).
It is legal to seek past the end of the file; an java.io.EOFException will be thrown only if a read is performed.
seek in interface ImageInputStream
seek in class ImageInputStreamImpl
pos - a long containing the desired file pointer position.IOException - if any other I/O error occurs.public void close()
throws IOException Description copied from interface: ImageInputStream
Closes the stream. Attempts to access a stream that has been closed may result in IOExceptions or incorrect behavior. Calling this method may allow classes implementing this interface to release resources associated with the stream such as memory, disk space, or file descriptors.
close in interface Closeable
close in interface AutoCloseable
close in interface ImageInputStream
close in class ImageInputStreamImpl
IOException - if an I/O error occurs.protected void finalize()
throws Throwable Finalizes this object prior to garbage collection. The close method is called to close any open input source. This method should not be called from application code.
finalize in class ImageInputStreamImpl
Throwable - if an error occurs during superclass finalization.WeakReference, PhantomReference
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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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