public interface ImageInputStream extends DataInput
ImageReaders
.Modifier and Type | Method and Description |
---|---|
void |
close() |
void |
flush() |
void |
flushBefore(long pos) |
int |
getBitOffset() |
ByteOrder |
getByteOrder() |
long |
getFlushedPosition() |
long |
getStreamPosition() |
boolean |
isCached() |
boolean |
isCachedFile() |
boolean |
isCachedMemory() |
long |
length() |
void |
mark() |
int |
read() |
int |
read(byte[] b) |
int |
read(byte[] b,
int offset,
int length) |
int |
readBit() |
long |
readBits(int numBits) |
boolean |
readBoolean()
Reads a byte and checks whether or not its value is zero.
|
byte |
readByte()
Reads a signed byte.
|
void |
readBytes(IIOByteBuffer buf,
int numBytes)
Reads up to a specified number of bytes, and modifies a
IIOByteBuffer to hold the read data. |
char |
readChar()
Reads an unsigned 16-bit integer.
|
double |
readDouble()
Reads an IEEE 64-bit double-precision floating point number.
|
float |
readFloat()
Reads an IEEE 32-bit single-precision floating point number.
|
void |
readFully(byte[] b)
Reads a sequence of signed 8-bit integers into a
byte[] array. |
void |
readFully(byte[] b,
int offset,
int numBytes)
Reads a sequence of signed 8-bit integers into a
byte[] array. |
void |
readFully(char[] c,
int offset,
int numChars)
Reads a sequence of unsigned 16-bit integers into a
char[] array. |
void |
readFully(double[] d,
int offset,
int numDoubles)
Reads a sequence of IEEE 64-bit double-precision floating point
numbers into a
double[] array. |
void |
readFully(float[] f,
int offset,
int numFloats)
Reads a sequence of IEEE 32-bit single-precision floating point
numbers into a
float[] array. |
void |
readFully(int[] i,
int offset,
int numInts)
Reads a sequence of signed 32-bit integers into a
long[] array. |
void |
readFully(long[] l,
int offset,
int numLongs)
Reads a sequence of signed 64-bit integers into a
long[] array. |
void |
readFully(short[] s,
int offset,
int numShorts)
Reads a sequence of signed 16-bit integers into a
short[] array. |
int |
readInt()
Reads a signed 32-bit integer.
|
String |
readLine()
This method reads the next line of text data from an input stream.
|
long |
readLong()
Reads a signed 64-bit integer.
|
short |
readShort()
Reads an signed 16-bit integer.
|
int |
readUnsignedByte()
Reads an unsigned byte.
|
long |
readUnsignedInt()
Reads an unsigned 32-bit integer.
|
int |
readUnsignedShort()
Reads an unsigned 16-bit integer.
|
String |
readUTF()
This method reads a
String from an input stream that is
encoded in a modified UTF-8 format. |
void |
reset() |
void |
seek(long pos) |
void |
setBitOffset(int bitOffset) |
void |
setByteOrder(ByteOrder order) |
int |
skipBytes(int numBytes)
This method skips and discards the specified number of bytes in an
input stream.
|
long |
skipBytes(long numBytes) |
void setByteOrder(ByteOrder order)
ByteOrder getByteOrder()
int read() throws IOException
IOException
int read(byte[] b) throws IOException
IOException
int read(byte[] b, int offset, int length) throws IOException
IOException
void readBytes(IIOByteBuffer buf, int numBytes) throws IOException
IIOByteBuffer
to hold the read data.
The bit offset is set to zero before any data is read.
buf
- an IIOByteBuffer
that will hold the read
data.numBytes
- the maximum number of bytes to read.IndexOutOfBoundsException
- if numBytes
is
negative.NullPointerException
- if buf
is
null
.IOException
- if some general problem happens with
accessing data.boolean readBoolean() throws IOException
The bit offset is set to zero before the byte is read.
readBoolean
in interface DataInput
boolean
value readEOFException
- if the input stream is at its end.IOException
- if some general problem happens with
accessing data.readBit()
,
readByte()
,
readFully(byte[], int, int)
byte readByte() throws IOException
The bit offset is set to zero before any data is read.
readByte
in interface DataInput
byte
value readEOFException
- if the input stream is at its end.IOException
- if some general problem happens with
accessing data.readUnsignedByte()
,
readFully(byte[], int, int)
int readUnsignedByte() throws IOException
The bit offset is set to zero before any data is read.
readUnsignedByte
in interface DataInput
int
.EOFException
- if the input stream is at its end.IOException
- if some general problem happens with
accessing data.readByte()
,
readFully(byte[], int, int)
short readShort() throws IOException
The bit offset is set to zero before any data is read.
readShort
in interface DataInput
short
value readEOFException
- if the input stream ends before all two
bytes were read.IOException
- if some general problem happens with
accessing data.readUnsignedShort()
,
readChar()
,
readFully(short[], int, int)
int readUnsignedShort() throws IOException
The bit offset is set to zero before any data is read.
This method does the same as readChar()
.
readUnsignedShort
in interface DataInput
int
.EOFException
- if the input stream ends before all two
bytes were read.IOException
- if some general problem happens with
accessing data.readShort()
,
readChar()
,
readFully(char[], int, int)
char readChar() throws IOException
The bit offset is set to zero before any data is read.
This method does the same as readUnsignedShort()
.
readChar
in interface DataInput
char
value readEOFException
- if the input stream ends before all two
bytes were read.IOException
- if some general problem happens with
accessing data.readFully(char[], int, int)
int readInt() throws IOException
The bit offset is set to zero before any data is read.
readInt
in interface DataInput
int
value readEOFException
- if the input stream ends before all four
bytes were read.IOException
- if some general problem happens with
accessing data.readUnsignedInt()
,
readFully(int[], int, int)
long readUnsignedInt() throws IOException
The bit offset is set to zero before any data is read.
EOFException
- if the input stream ends before all four
bytes were read.IOException
- if some general problem happens with
accessing data.readInt()
,
readFully(int[], int, int)
long readLong() throws IOException
The bit offset is set to zero before any data is read.
readLong
in interface DataInput
long
value readEOFException
- if the input stream ends before all eight
bytes were read.IOException
- if some general problem happens with
accessing data.readFully(long[], int, int)
float readFloat() throws IOException
The bit offset is set to zero before any data is read.
readFloat
in interface DataInput
float
value readEOFException
- if the input stream ends before all four
bytes were read.IOException
- if some general problem happens with
accessing data.readFully(float[], int, int)
double readDouble() throws IOException
The bit offset is set to zero before any data is read.
readDouble
in interface DataInput
double
value readEOFException
- if the input stream ends before all eight
bytes were read.IOException
- if some general problem happens with
accessing data.readFully(double[], int, int)
String readLine() throws IOException
DataInput
char
values by treating the byte read as the low eight bits of the
char
and using 0 as the high eight bits. Because of this,
it does not support the full 16-bit Unicode character set.
The reading of bytes ends when either the end of file or a line terminator
is encountered. The bytes read are then returned as a
String
.
A line terminator is a byte sequence consisting of either
\r
, \n
or \r\n
. These termination
charaters are discarded and are not returned as part of the string.
A line is also terminated by an end of file condition.
readLine
in interface DataInput
String
IOException
- If an error occursString readUTF() throws IOException
DataInput
String
from an input stream that is
encoded in a modified UTF-8 format. This format has a leading two byte
sequence that contains the remaining number of bytes to read.
This two byte
sequence is read using the readUnsignedShort()
method of this
interface.
After the number of remaining bytes have been determined, these bytes
are read an transformed into char
values. These
char
values are encoded in the stream using either a one,
two, or three byte format.
The particular format in use can be determined by examining the first
byte read.
If the first byte has a high order bit of 0, then
that character consists on only one byte. This character value consists
of seven bits that are at positions 0 through 6 of the byte. As an
example, if byte1
is the byte read from the stream, it would
be converted to a char
like so:
(char)byte1
If the first byte has 110 as its high order bits, then the character consists of two bytes. The bits that make up the character value are in positions 0 through 4 of the first byte and bit positions 0 through 5 of the second byte. (The second byte should have 10 as its high order bits). These values are in most significant byte first (i.e., "big endian") order.
As an example, if byte1
and byte2
are the first
two bytes read respectively, and the high order bits of them match the
patterns which indicate a two byte character encoding, then they would be
converted to a Java char
like so:
(char)(((byte1 & 0x1F) << 6) + (byte2 & 0x3F))
If the first byte has a 1110 as its high order bits, then the character consists of three bytes. The bits that make up the character value are in positions 0 through 3 of the first byte and bit positions 0 through 5 of the other two bytes. (The second and third bytes should have 10 as their high order bits). These values are in most significant byte first (i.e., "big endian") order.
As an example, if byte1
, byte2
, and
byte3
are the three bytes read, and the high order bits of
them match the patterns which indicate a three byte character encoding,
then they would be converted to a Java char
like so:
(char)(((byte1 & 0x0F) << 12) + ((byte2 & 0x3F) + (byte3 & 0x3F))
Note that all characters are encoded in the method that requires the
fewest number of bytes with the exception of the character with the
value of \<llll>u0000
which is encoded as two bytes.
This is a modification of the UTF standard used to prevent C language
style NUL
values from appearing in the byte stream.
This method can read data that was written by an object implementing the
writeUTF()
method in DataOutput
.
readUTF
in interface DataInput
String
readEOFException
- If end of file is reached before reading the
StringUTFDataFormatException
- If the data is not in UTF-8 formatIOException
- If any other error occursDataOutput.writeUTF(java.lang.String)
void readFully(byte[] b, int offset, int numBytes) throws IOException
byte[]
array.
The bit offset is set to zero before any data is read.
readFully
in interface DataInput
b
- an array for storing the read values.offset
- the index of the first element in b
that will hold read data.numBytes
- the number of bytes to read.IndexOutOfBoundsException
- if offset
or
numBytes
is negative, or if offset +
numBytes
exceeds b.length
.NullPointerException
- if b
is
null
.EOFException
- if the input stream ends before all content
was read.IOException
- if some general problem happens with
accessing data.readByte()
void readFully(byte[] b) throws IOException
byte[]
array.
The bit offset is set to zero before any data is read.
readFully
in interface DataInput
b
- an array for storing the read values.NullPointerException
- if b
is
null
.EOFException
- if the input stream ends before all content
was read.IOException
- if some general problem happens with
accessing data.readByte()
,
readFully(byte[], int, int)
void readFully(short[] s, int offset, int numShorts) throws IOException
short[]
array. If necessary, values are converted
from the stream’s current byte
order.
The bit offset is set to zero before any data is read.
s
- an array for storing the read values.offset
- the index of the first element in s
that will hold read data.numShorts
- the number of signed 16-bit integers to read
(which is one half of the number of bytes).IndexOutOfBoundsException
- if offset
or
numShorts
is negative, or if offset +
numShorts
exceeds s.length
.NullPointerException
- if s
is
null
.EOFException
- if the input stream ends before all content
was read.IOException
- if some general problem happens with
accessing data.readShort()
void readFully(char[] c, int offset, int numChars) throws IOException
char[]
array. If necessary, values are converted
from the stream’s current byte
order.
The bit offset is set to zero before any data is read.
c
- an array for storing the read values.offset
- the index of the first element in c
that will hold read data.numChars
- the number of unsigned 16-bit integers to read
(which is one half of the number of bytes).IndexOutOfBoundsException
- if offset
or
numChars
is negative, or if offset +
numChars
exceeds c.length
.NullPointerException
- if c
is
null
.EOFException
- if the input stream ends before all content
was read.IOException
- if some general problem happens with
accessing data.readChar()
void readFully(int[] i, int offset, int numInts) throws IOException
long[]
array. If necessary, values are converted
from the stream’s current byte
order.
The bit offset is set to zero before any data is read.
i
- an array for storing the read values.offset
- the index of the first element in i
that will hold read data.numInts
- the number of signed 32-bit integers to read
(which is one fourth of the number of bytes).IndexOutOfBoundsException
- if offset
or
numInts
is negative, or if offset +
numInts
exceeds i.length
.NullPointerException
- if i
is
null
.EOFException
- if the input stream ends before all content
was read.IOException
- if some general problem happens with
accessing data.readInt()
void readFully(long[] l, int offset, int numLongs) throws IOException
long[]
array. If necessary, values are converted
from the stream’s current byte
order.
The bit offset is set to zero before any data is read.
l
- an array for storing the read values.offset
- the index of the first element in l
that will hold read data.numLongs
- the number of signed 64-bit integers to read
(which is one eight of the number of bytes).IndexOutOfBoundsException
- if offset
or
numLongs
is negative, or if offset +
numLongs
exceeds l.length
.NullPointerException
- if l
is
null
.EOFException
- if the input stream ends before all content
was read.IOException
- if some general problem happens with
accessing data.readLong()
void readFully(float[] f, int offset, int numFloats) throws IOException
float[]
array. If necessary, values
are converted from the stream’s current byte order.
The bit offset is set to zero before any data is read.
d
- an array for storing the read values.offset
- the index of the first element in d
that will hold read data.numFloats
- the number of IEEE 32-bit single-precision
floating point numbers to read (which is one fourth of the number
of bytes).IndexOutOfBoundsException
- if offset
or
numFloats
is negative, or if offset +
numFloats
exceeds f.length
.NullPointerException
- if f
is
null
.EOFException
- if the input stream ends before all content
was read.IOException
- if some general problem happens with
accessing data.readFloat()
void readFully(double[] d, int offset, int numDoubles) throws IOException
double[]
array. If necessary, values
are converted from the stream’s current byte order.
The bit offset is set to zero before any data is read.
d
- an array for storing the read values.offset
- the index of the first element in d
that will hold read data.numDoubles
- the number of IEEE 64-bit double-precision
floating point numbers to read (which is one eight of the number
of bytes).IndexOutOfBoundsException
- if offset
or
numDoubles
is negative, or if offset +
numDoubles
exceeds d.length
.NullPointerException
- if d
is
null
.EOFException
- if the input stream ends before all content
was read.IOException
- if some general problem happens with
accessing data.readDouble()
long getStreamPosition() throws IOException
IOException
int getBitOffset() throws IOException
IOException
void setBitOffset(int bitOffset) throws IOException
IOException
int readBit() throws IOException
IOException
long readBits(int numBits) throws IOException
IOException
long length() throws IOException
IOException
int skipBytes(int numBytes) throws IOException
DataInput
skipBytes
in interface DataInput
numBytes
- The number of bytes to skipnumBytes
EOFException
- If end of file is reached before all bytes can be
skippedIOException
- If any other error occurslong skipBytes(long numBytes) throws IOException
IOException
void seek(long pos) throws IOException
IOException
void mark()
void reset() throws IOException
IOException
void flushBefore(long pos) throws IOException
IOException
void flush() throws IOException
IOException
long getFlushedPosition()
boolean isCached()
boolean isCachedMemory()
boolean isCachedFile()
void close() throws IOException
IOException