Class ImageOutputStreamImpl
- All Implemented Interfaces:
Closeable, DataInput, DataOutput, AutoCloseable, ImageInputStream, ImageOutputStream
- Direct Known Subclasses:
FileCacheImageOutputStream, FileImageOutputStream, MemoryCacheImageOutputStream
ImageOutputStream
interface.
This class is designed to reduce the number of methods that must
be implemented by subclasses.-
Field Summary
Fields declared in class ImageInputStreamImpl
bitOffset, byteOrder, flushedPos, streamPos
Modifier and TypeFieldDescriptionprotected int
The current bit offset within the stream.protected ByteOrder
The byte order of the stream as an instance of the enumeration classjava.nio.ByteOrder
, whereByteOrder.BIG_ENDIAN
indicates network byte order andByteOrder.LITTLE_ENDIAN
indicates the reverse order.protected long
The position prior to which data may be discarded.protected long
The current read position within the stream. -
Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionprotected final void
If the bit offset is non-zero, forces the remaining bits in the current byte to 0 and advances the stream position by one.void
write
(byte[] b) Writes a sequence of bytes to the stream at the current position.void
writeBit
(int bit) Writes a single bit, given by the least significant bit of the argument, to the stream at the current bit offset within the current byte position.void
writeBits
(long bits, int numBits) Writes a sequence of bits, given by thenumBits
least significant bits of thebits
argument in left-to-right order, to the stream at the current bit offset within the current byte position.void
writeBoolean
(boolean v) Writes aboolean
value to the stream.void
writeByte
(int v) Writes the 8 low-order bits ofv
to the stream.void
writeBytes
(String s) Writes a string to the output stream.void
writeChar
(int v) This method is a synonym forwriteShort
.void
writeChars
(char[] c, int off, int len) Writes a sequence of chars to the stream at the current position.void
writeChars
(String s) Writes a string to the output stream.void
writeDouble
(double v) Writes adouble
value, which is comprised of four bytes, to the output stream.void
writeDoubles
(double[] d, int off, int len) Writes a sequence of doubles to the stream at the current position.void
writeFloat
(float v) Writes afloat
value, which is comprised of four bytes, to the output stream.void
writeFloats
(float[] f, int off, int len) Writes a sequence of floats to the stream at the current position.void
writeInt
(int v) Writes the 32 bits ofv
to the stream.void
writeInts
(int[] i, int off, int len) Writes a sequence of ints to the stream at the current position.void
writeLong
(long v) Writes the 64 bits ofv
to the stream.void
writeLongs
(long[] l, int off, int len) Writes a sequence of longs to the stream at the current position.void
writeShort
(int v) Writes the 16 low-order bits ofv
to the stream.void
writeShorts
(short[] s, int off, int len) Writes a sequence of shorts to the stream at the current position.void
Writes two bytes of length information to the output stream in network byte order, followed by the modified UTF-8 representation of every character in the strings
.Methods declared in class ImageInputStreamImpl
checkClosed, close, flush, flushBefore, getBitOffset, getByteOrder, getFlushedPosition, getStreamPosition, isCached, isCachedFile, isCachedMemory, 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, seek, setBitOffset, setByteOrder, skipBytes, skipBytes
Modifier and TypeMethodDescriptionprotected final void
Throws anIOException
if the stream has been closed.void
close()
Closes the stream.void
flush()
Discards the initial position of the stream prior to the current stream position.void
flushBefore
(long pos) Discards the initial portion of the stream prior to the indicated position.int
Returns the current bit offset, as an integer between 0 and 7, inclusive.Returns the byte order with which data values will be read from this stream as an instance of thejava.nio.ByteOrder
enumeration.long
Returns the earliest position in the stream to which seeking may be performed.long
Returns the current byte position of the stream.boolean
isCached()
Default implementation returns false.boolean
Default implementation returns false.boolean
Default implementation returns false.long
length()
Returns-1L
to indicate that the stream has unknown length.void
mark()
Pushes the current stream position onto a stack of marked positions.abstract int
read()
Reads a single byte from the stream and returns it as anint
between 0 and 255.int
read
(byte[] b) A convenience method that callsread(b, 0, b.length)
.abstract int
read
(byte[] b, int off, int len) Reads up tolen
bytes from the stream, and stores them intob
starting at indexoff
.int
readBit()
Reads a single bit from the stream and returns it as anint
with the value0
or1
.long
readBits
(int numBits) Reads a bitstring from the stream and returns it as along
, with the first bit read becoming the most significant bit of the output.boolean
Reads a byte from the stream and returns aboolean
value oftrue
if it is nonzero,false
if it is zero.byte
readByte()
Reads a byte from the stream and returns it as abyte
value.void
readBytes
(IIOByteBuffer buf, int len) Reads up tolen
bytes from the stream, and modifies the suppliedIIOByteBuffer
to indicate the byte array, offset, and length where the data may be found.char
readChar()
Equivalent toreadUnsignedShort
, except that the result is returned using thechar
datatype.double
Reads 8 bytes from the stream, and (conceptually) concatenates them according to the current byte order and returns the result as adouble
.float
Reads 4 bytes from the stream, and (conceptually) concatenates them according to the current byte order and returns the result as afloat
.void
readFully
(byte[] b) Readsb.length
bytes from the stream, and stores them intob
starting at index0
.void
readFully
(byte[] b, int off, int len) Readslen
bytes from the stream, and stores them intob
starting at indexoff
.void
readFully
(char[] c, int off, int len) Readslen
chars (unsigned 16-bit integers) from the stream according to the current byte order, and stores them intoc
starting at indexoff
.void
readFully
(double[] d, int off, int len) Readslen
doubles (64-bit IEEE double-precision floats) from the stream according to the current byte order, and stores them intod
starting at indexoff
.void
readFully
(float[] f, int off, int len) Readslen
floats (32-bit IEEE single-precision floats) from the stream according to the current byte order, and stores them intof
starting at indexoff
.void
readFully
(int[] i, int off, int len) Readslen
ints (signed 32-bit integers) from the stream according to the current byte order, and stores them intoi
starting at indexoff
.void
readFully
(long[] l, int off, int len) Readslen
longs (signed 64-bit integers) from the stream according to the current byte order, and stores them intol
starting at indexoff
.void
readFully
(short[] s, int off, int len) Readslen
shorts (signed 16-bit integers) from the stream according to the current byte order, and stores them intos
starting at indexoff
.int
readInt()
Reads 4 bytes from the stream, and (conceptually) concatenates them according to the current byte order and returns the result as anint
.readLine()
Reads the next line of text from the input stream.long
readLong()
Reads 8 bytes from the stream, and (conceptually) concatenates them according to the current byte order and returns the result as along
.short
Reads two bytes from the stream, and (conceptually) concatenates them according to the current byte order, and returns the result as ashort
value.int
Reads a byte from the stream, and (conceptually) converts it to an int, masks it with0xff
in order to strip off any sign-extension bits, and returns it as abyte
value.long
Reads 4 bytes from the stream, and (conceptually) concatenates them according to the current byte order, converts the result to a long, masks it with0xffffffffL
in order to strip off any sign-extension bits, and returns the result as an unsignedlong
value.int
Reads two bytes from the stream, and (conceptually) concatenates them according to the current byte order, converts the resulting value to anint
, masks it with0xffff
in order to strip off any sign-extension buts, and returns the result as an unsignedint
value.readUTF()
Reads in a string that has been encoded using a modified UTF-8 format.void
reset()
Resets the current stream byte and bit positions from the stack of marked positions.void
seek
(long pos) Sets the current stream position to the desired location.void
setBitOffset
(int bitOffset) Sets the bit offset to an integer between 0 and 7, inclusive.void
setByteOrder
(ByteOrder byteOrder) Sets the desired byte order for future reads of data values from this stream.int
skipBytes
(int n) Advances the current stream position by callingseek(getStreamPosition() + n)
.long
skipBytes
(long n) Advances the current stream position by callingseek(getStreamPosition() + n)
.Methods declared in class Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Modifier and TypeMethodDescriptionprotected Object
clone()
Creates and returns a copy of this object.boolean
Indicates whether some other object is "equal to" this one.protected void
finalize()
Deprecated, for removal: This API element is subject to removal in a future version.Finalization is deprecated and subject to removal in a future release.final Class
<?> getClass()
Returns the runtime class of thisObject
.int
hashCode()
Returns a hash code value for this object.final void
notify()
Wakes up a single thread that is waiting on this object's monitor.final void
Wakes up all threads that are waiting on this object's monitor.toString()
Returns a string representation of the object.final void
wait()
Causes the current thread to wait until it is awakened, typically by being notified or interrupted.final void
wait
(long timeoutMillis) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.final void
wait
(long timeoutMillis, int nanos) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.Methods declared in interface ImageOutputStream
flushBefore, write, write
Modifier and TypeMethodDescriptionvoid
flushBefore
(long pos) Flushes all data prior to the given position to the underlying destination, such as anOutputStream
orFile
.void
write
(byte[] b, int off, int len) Writes a sequence of bytes to the stream at the current position.void
write
(int b) Writes a single byte to the stream at the current position.
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Constructor Details
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ImageOutputStreamImpl
public ImageOutputStreamImpl()Constructs anImageOutputStreamImpl
.
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Method Details
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write
Description copied from interface:ImageOutputStream
Writes a sequence of bytes to the stream at the current position. Ifb.length
is 0, nothing is written. The byteb[0]
is written first, then the byteb[1]
, and so on.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
write
in interfaceDataOutput
- Specified by:
write
in interfaceImageOutputStream
- Parameters:
b
- an array ofbyte
s to be written.- Throws:
IOException
- if an I/O error occurs.
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writeBoolean
Description copied from interface:ImageOutputStream
Writes aboolean
value to the stream. Ifv
is true, the value(byte)1
is written; ifv
is false, the value(byte)0
is written.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeBoolean
in interfaceDataOutput
- Specified by:
writeBoolean
in interfaceImageOutputStream
- Parameters:
v
- theboolean
to be written.- Throws:
IOException
- if an I/O error occurs.
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writeByte
Description copied from interface:ImageOutputStream
Writes the 8 low-order bits ofv
to the stream. The 24 high-order bits ofv
are ignored. (This means thatwriteByte
does exactly the same thing aswrite
for an integer argument.)If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeByte
in interfaceDataOutput
- Specified by:
writeByte
in interfaceImageOutputStream
- Parameters:
v
- anint
containing the byte value to be written.- Throws:
IOException
- if an I/O error occurs.
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writeShort
Description copied from interface:ImageOutputStream
Writes the 16 low-order bits ofv
to the stream. The 16 high-order bits ofv
are ignored. If the stream uses network byte order, the bytes written, in order, will be:(byte)((v >> 8) & 0xff) (byte)(v & 0xff)
Otherwise, the bytes written will be:(byte)(v & 0xff) (byte)((v >> 8) & 0xff)
If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeShort
in interfaceDataOutput
- Specified by:
writeShort
in interfaceImageOutputStream
- Parameters:
v
- anint
containing the short value to be written.- Throws:
IOException
- if an I/O error occurs.
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writeChar
Description copied from interface:ImageOutputStream
This method is a synonym forwriteShort
.- Specified by:
writeChar
in interfaceDataOutput
- Specified by:
writeChar
in interfaceImageOutputStream
- Parameters:
v
- anint
containing the char (unsigned short) value to be written.- Throws:
IOException
- if an I/O error occurs.- See Also:
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writeInt
Description copied from interface:ImageOutputStream
Writes the 32 bits ofv
to the stream. If the stream uses network byte order, the bytes written, in order, will be:(byte)((v >> 24) & 0xff) (byte)((v >> 16) & 0xff) (byte)((v >> 8) & 0xff) (byte)(v & 0xff)
Otherwise, the bytes written will be:(byte)(v & 0xff) (byte)((v >> 8) & 0xff) (byte)((v >> 16) & 0xff) (byte)((v >> 24) & 0xff)
If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeInt
in interfaceDataOutput
- Specified by:
writeInt
in interfaceImageOutputStream
- Parameters:
v
- anint
containing the value to be written.- Throws:
IOException
- if an I/O error occurs.
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writeLong
Description copied from interface:ImageOutputStream
Writes the 64 bits ofv
to the stream. If the stream uses network byte order, the bytes written, in order, will be:(byte)((v >> 56) & 0xff) (byte)((v >> 48) & 0xff) (byte)((v >> 40) & 0xff) (byte)((v >> 32) & 0xff) (byte)((v >> 24) & 0xff) (byte)((v >> 16) & 0xff) (byte)((v >> 8) & 0xff) (byte)(v & 0xff)
Otherwise, the bytes written will be:(byte)(v & 0xff) (byte)((v >> 8) & 0xff) (byte)((v >> 16) & 0xff) (byte)((v >> 24) & 0xff) (byte)((v >> 32) & 0xff) (byte)((v >> 40) & 0xff) (byte)((v >> 48) & 0xff) (byte)((v >> 56) & 0xff)
If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeLong
in interfaceDataOutput
- Specified by:
writeLong
in interfaceImageOutputStream
- Parameters:
v
- along
containing the value to be written.- Throws:
IOException
- if an I/O error occurs.
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writeFloat
Description copied from interface:ImageOutputStream
Writes afloat
value, which is comprised of four bytes, to the output stream. It does this as if it first converts thisfloat
value to anint
in exactly the manner of theFloat.floatToIntBits
method and then writes the int value in exactly the manner of thewriteInt
method.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeFloat
in interfaceDataOutput
- Specified by:
writeFloat
in interfaceImageOutputStream
- Parameters:
v
- afloat
containing the value to be written.- Throws:
IOException
- if an I/O error occurs.
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writeDouble
Description copied from interface:ImageOutputStream
Writes adouble
value, which is comprised of four bytes, to the output stream. It does this as if it first converts thisdouble
value to along
in exactly the manner of theDouble.doubleToLongBits
method and then writes the long value in exactly the manner of thewriteLong
method.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeDouble
in interfaceDataOutput
- Specified by:
writeDouble
in interfaceImageOutputStream
- Parameters:
v
- adouble
containing the value to be written.- Throws:
IOException
- if an I/O error occurs.
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writeBytes
Description copied from interface:ImageOutputStream
Writes a string to the output stream. For every character in the strings
, taken in order, one byte is written to the output stream. Ifs
isnull
, aNullPointerException
is thrown.If
s.length
is zero, then no bytes are written. Otherwise, the characters[0]
is written first, thens[1]
, and so on; the last character written iss[s.length-1]
. For each character, one byte is written, the low-order byte, in exactly the manner of thewriteByte
method. The high-order eight bits of each character in the string are ignored.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeBytes
in interfaceDataOutput
- Specified by:
writeBytes
in interfaceImageOutputStream
- Parameters:
s
- aString
containing the value to be written.- Throws:
IOException
- if an I/O error occurs.
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writeChars
Description copied from interface:ImageOutputStream
Writes a string to the output stream. For every character in the strings
, taken in order, two bytes are written to the output stream, ordered according to the current byte order setting. If network byte order is being used, the high-order byte is written first; the order is reversed otherwise. Ifs
isnull
, aNullPointerException
is thrown.If
s.length
is zero, then no bytes are written. Otherwise, the characters[0]
is written first, thens[1]
, and so on; the last character written iss[s.length-1]
.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeChars
in interfaceDataOutput
- Specified by:
writeChars
in interfaceImageOutputStream
- Parameters:
s
- aString
containing the value to be written.- Throws:
IOException
- if an I/O error occurs.
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writeUTF
Description copied from interface:ImageOutputStream
Writes two bytes of length information to the output stream in network byte order, followed by the modified UTF-8 representation of every character in the strings
. Ifs
isnull
, aNullPointerException
is thrown. Each character in the strings
is converted to a group of one, two, or three bytes, depending on the value of the character.If a character
c
is in the range\u0001
through\u007f
, it is represented by one byte:(byte)c
If a character
c
is\u0000
or is in the range\u0080
through\u07ff
, then it is represented by two bytes, to be written in the order shown:(byte)(0xc0 | (0x1f & (c >> 6))) (byte)(0x80 | (0x3f & c))
If a character
c
is in the range\u0800
throughuffff
, then it is represented by three bytes, to be written in the order shown:(byte)(0xe0 | (0x0f & (c >> 12))) (byte)(0x80 | (0x3f & (c >> 6))) (byte)(0x80 | (0x3f & c))
First, the total number of bytes needed to represent all the characters of
s
is calculated. If this number is larger than65535
, then aUTFDataFormatException
is thrown. Otherwise, this length is written to the output stream in exactly the manner of thewriteShort
method; after this, the one-, two-, or three-byte representation of each character in the strings
is written.The current byte order setting is ignored.
If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
Note: This method should not be used in the implementation of image formats that use standard UTF-8, because the modified UTF-8 used here is incompatible with standard UTF-8.
- Specified by:
writeUTF
in interfaceDataOutput
- Specified by:
writeUTF
in interfaceImageOutputStream
- Parameters:
s
- aString
containing the value to be written.- Throws:
UTFDataFormatException
- if the modified UTF-8 representation ofs
requires more than 65536 bytes.IOException
- if an I/O error occurs.
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writeShorts
Description copied from interface:ImageOutputStream
Writes a sequence of shorts to the stream at the current position. Iflen
is 0, nothing is written. The shorts[off]
is written first, then the shorts[off + 1]
, and so on. The byte order of the stream is used to determine the order in which the individual bytes are written.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeShorts
in interfaceImageOutputStream
- Parameters:
s
- an array ofshort
s to be written.off
- the start offset in the data.len
- the number ofshort
s to write.- Throws:
IOException
- if an I/O error occurs.
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writeChars
Description copied from interface:ImageOutputStream
Writes a sequence of chars to the stream at the current position. Iflen
is 0, nothing is written. The charc[off]
is written first, then the charc[off + 1]
, and so on. The byte order of the stream is used to determine the order in which the individual bytes are written.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeChars
in interfaceImageOutputStream
- Parameters:
c
- an array ofchar
s to be written.off
- the start offset in the data.len
- the number ofchar
s to write.- Throws:
IOException
- if an I/O error occurs.
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writeInts
Description copied from interface:ImageOutputStream
Writes a sequence of ints to the stream at the current position. Iflen
is 0, nothing is written. The inti[off]
is written first, then the inti[off + 1]
, and so on. The byte order of the stream is used to determine the order in which the individual bytes are written.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeInts
in interfaceImageOutputStream
- Parameters:
i
- an array ofint
s to be written.off
- the start offset in the data.len
- the number ofint
s to write.- Throws:
IOException
- if an I/O error occurs.
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writeLongs
Description copied from interface:ImageOutputStream
Writes a sequence of longs to the stream at the current position. Iflen
is 0, nothing is written. The longl[off]
is written first, then the longl[off + 1]
, and so on. The byte order of the stream is used to determine the order in which the individual bytes are written.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeLongs
in interfaceImageOutputStream
- Parameters:
l
- an array oflong
s to be written.off
- the start offset in the data.len
- the number oflong
s to write.- Throws:
IOException
- if an I/O error occurs.
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writeFloats
Description copied from interface:ImageOutputStream
Writes a sequence of floats to the stream at the current position. Iflen
is 0, nothing is written. The floatf[off]
is written first, then the floatf[off + 1]
, and so on. The byte order of the stream is used to determine the order in which the individual bytes are written.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeFloats
in interfaceImageOutputStream
- Parameters:
f
- an array offloat
s to be written.off
- the start offset in the data.len
- the number offloat
s to write.- Throws:
IOException
- if an I/O error occurs.
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writeDoubles
Description copied from interface:ImageOutputStream
Writes a sequence of doubles to the stream at the current position. Iflen
is 0, nothing is written. The doubled[off]
is written first, then the doubled[off + 1]
, and so on. The byte order of the stream is used to determine the order in which the individual bytes are written.If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write.
- Specified by:
writeDoubles
in interfaceImageOutputStream
- Parameters:
d
- an array ofdoubles
s to be written.off
- the start offset in the data.len
- the number ofdouble
s to write.- Throws:
IOException
- if an I/O error occurs.
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writeBit
Description copied from interface:ImageOutputStream
Writes a single bit, given by the least significant bit of the argument, to the stream at the current bit offset within the current byte position. The upper 31 bits of the argument are ignored. The given bit replaces the previous bit at that position. The bit offset is advanced by one and reduced modulo 8.If any bits of a particular byte have never been set at the time the byte is flushed to the destination, those bits will be set to 0 automatically.
- Specified by:
writeBit
in interfaceImageOutputStream
- Parameters:
bit
- anint
whose least significant bit is to be written to the stream.- Throws:
IOException
- if an I/O error occurs.
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writeBits
Description copied from interface:ImageOutputStream
Writes a sequence of bits, given by thenumBits
least significant bits of thebits
argument in left-to-right order, to the stream at the current bit offset within the current byte position. The upper64 - numBits
bits of the argument are ignored. The bit offset is advanced bynumBits
and reduced modulo 8. Note that a bit offset of 0 always indicates the most-significant bit of the byte, and bytes of bits are written out in sequence as they are encountered. Thus bit writes are always effectively in network byte order. The actual stream byte order setting is ignored.Bit data may be accumulated in memory indefinitely, until
flushBefore
is called. At that time, all bit data prior to the flushed position will be written.If any bits of a particular byte have never been set at the time the byte is flushed to the destination, those bits will be set to 0 automatically.
- Specified by:
writeBits
in interfaceImageOutputStream
- Parameters:
bits
- along
containing the bits to be written, starting with the bit in positionnumBits - 1
down to the least significant bit.numBits
- anint
between 0 and 64, inclusive.- Throws:
IOException
- if an I/O error occurs.
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flushBits
If the bit offset is non-zero, forces the remaining bits in the current byte to 0 and advances the stream position by one. This method should be called by subclasses at the beginning of thewrite(int)
andwrite(byte[], int, int)
methods.- Throws:
IOException
- if an I/O error occurs.
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