Class FileImageInputStream
java.lang.Object
javax.imageio.stream.ImageInputStreamImpl
javax.imageio.stream.FileImageInputStream
- All Implemented Interfaces:
Closeable,DataInput,AutoCloseable,ImageInputStream
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.-
Field Summary
Fields declared in class javax.imageio.stream.ImageInputStreamImpl
bitOffset, byteOrder, flushedPos, streamPos -
Constructor Summary
ConstructorsConstructorDescriptionConstructs aFileImageInputStreamthat will read from a givenFile.Constructs aFileImageInputStreamthat will read from a givenRandomAccessFile. -
Method Summary
Modifier and TypeMethodDescriptionprotected voidfinalize()Deprecated, for removal: This API element is subject to removal in a future version.Finalization has been deprecated for removal.longlength()Returns the length of the underlying file, or-1if it is unknown.intread()Reads a single byte from the stream and returns it as anintbetween 0 and 255.intread(byte[] b, int off, int len) Reads up tolenbytes from the stream, and stores them intobstarting at indexoff.Methods declared in class javax.imageio.stream.ImageInputStreamImpl
checkClosed, close, 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, seek, setBitOffset, setByteOrder, skipBytes, skipBytes
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Constructor Details
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FileImageInputStream
Constructs aFileImageInputStreamthat will read from a givenFile.The file contents must not change between the time this object is constructed and the time of the last call to a read method.
- Parameters:
f- aFileto read from.- Throws:
IllegalArgumentException- iffisnull.FileNotFoundException- iffis a directory or cannot be opened for reading for any other reason.IOException- if an I/O error occurs.
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FileImageInputStream
Constructs aFileImageInputStreamthat will read from a givenRandomAccessFile.The file contents must not change between the time this object is constructed and the time of the last call to a read method.
- Parameters:
raf- aRandomAccessFileto read from.- Throws:
IllegalArgumentException- ifrafisnull.
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Method Details
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read
Description copied from class:ImageInputStreamImplReads a single byte from the stream and returns it as anintbetween 0 and 255. If EOF is reached,-1is 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:
readin interfaceImageInputStream- Specified by:
readin classImageInputStreamImpl- Returns:
- the value of the next byte in the stream, or
-1if EOF is reached. - Throws:
IOException- if the stream has been closed.
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read
Description copied from class:ImageInputStreamImplReads up tolenbytes from the stream, and stores them intobstarting at indexoff. If no bytes can be read because the end of the stream has been reached,-1is 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.
- Specified by:
readin interfaceImageInputStream- Specified by:
readin classImageInputStreamImpl- Parameters:
b- an array of bytes to be written to.off- the starting position withinbto write to.len- the maximum number of bytes to read.- Returns:
- the number of bytes actually read, or
-1to indicate EOF. - Throws:
IOException- if an I/O error occurs.
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length
public long length()Returns the length of the underlying file, or-1if it is unknown.- Specified by:
lengthin interfaceImageInputStream- Overrides:
lengthin classImageInputStreamImpl- Returns:
- the file length as a
long, or-1.
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finalize
Deprecated, for removal: This API element is subject to removal in a future version.Finalization has been deprecated for removal. SeeObject.finalize()for background information and details about migration options.Finalizes this object prior to garbage collection. Theclosemethod is called to close any open input source. This method should not be called from application code.- Overrides:
finalizein classImageInputStreamImpl- Throws:
Throwable- if an error occurs during superclass finalization.- See Also:
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