public class FileImageInputStream extends ImageInputStreamImpl
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| Constructor and Description |
|---|
FileImageInputStream(File f)
Constructs a
FileImageInputStream that will read
from a given File. |
FileImageInputStream(RandomAccessFile raf)
Constructs a
FileImageInputStream that will read
from a given RandomAccessFile. |
| Modifier and Type | Method and Description |
|---|---|
void |
close()
Closes the stream.
|
protected void |
finalize()
Finalizes this object prior to garbage collection.
|
long |
length()
Returns the length of the underlying file, or
-1
if it is unknown. |
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. |
void |
seek(long pos)
Sets the current stream position to the desired location.
|
checkClosed, flush, flushBefore, getBitOffset, getByteOrder, getFlushedPosition, getStreamPosition, isCached, isCachedFile, isCachedMemory, 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, setBitOffset, setByteOrder, skipBytes, skipBytespublic FileImageInputStream(File f) throws FileNotFoundException, IOException
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)
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
ImageInputStreamImplint 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 ImageInputStreamread 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
ImageInputStreamImpllen 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 ImageInputStreamread in class ImageInputStreamImplb - 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()
-1
if it is unknown.length in interface ImageInputStreamlength in class ImageInputStreamImpllong, or
-1.public void seek(long pos)
throws IOException
ImageInputStream 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 ImageInputStreamseek in class ImageInputStreamImplpos - a long containing the desired file
pointer position.IOException - if any other I/O error occurs.public void close()
throws IOException
ImageInputStreamIOExceptions 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 Closeableclose in interface AutoCloseableclose in interface ImageInputStreamclose in class ImageInputStreamImplIOException - if an I/O error occurs.protected void finalize()
throws Throwable
close method is called to close any open input
source. This method should not be called from application
code.finalize in class ImageInputStreamImplThrowable - if an error occurs during superclass
finalization.WeakReference,
PhantomReference Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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