javax.imageio.stream
Interface ImageInputStream

All Superinterfaces:
DataInput
All Known Subinterfaces:
ImageOutputStream
All Known Implementing Classes:
FileCacheImageInputStream, FileCacheImageOutputStream, FileImageInputStream, FileImageOutputStream, ImageInputStreamImpl, ImageOutputStreamImpl, MemoryCacheImageInputStream, MemoryCacheImageOutputStream

public interface ImageInputStream
extends DataInput

An input stream for use by ImageReaders.

Since:
1.4

Method Summary
 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)
           
 

Method Detail

setByteOrder

void setByteOrder(ByteOrder order)

getByteOrder

ByteOrder getByteOrder()

read

int read()
         throws IOException
Throws:
IOException

read

int read(byte[] b)
         throws IOException
Throws:
IOException

read

int read(byte[] b,
         int offset,
         int length)
         throws IOException
Throws:
IOException

readBytes

void readBytes(IIOByteBuffer buf,
               int numBytes)
               throws IOException
Reads up to a specified number of bytes, and modifies a IIOByteBuffer to hold the read data.

The bit offset is set to zero before any data is read.

Parameters:
buf - an IIOByteBuffer that will hold the read data.
numBytes - the maximum number of bytes to read.
Throws:
IndexOutOfBoundsException - if numBytes is negative.
NullPointerException - if buf is null.
IOException - if some general problem happens with accessing data.

readBoolean

boolean readBoolean()
                    throws IOException
Reads a byte and checks whether or not its value is zero.

The bit offset is set to zero before the byte is read.

Specified by:
readBoolean in interface DataInput
Returns:
The boolean value read
Throws:
EOFException - if the input stream is at its end.
IOException - if some general problem happens with accessing data.
See Also:
readBit(), readByte(), readFully(byte[], int, int)

readByte

byte readByte()
              throws IOException
Reads a signed byte.

The bit offset is set to zero before any data is read.

Specified by:
readByte in interface DataInput
Returns:
The byte value read
Throws:
EOFException - if the input stream is at its end.
IOException - if some general problem happens with accessing data.
See Also:
readUnsignedByte(), readFully(byte[], int, int)

readUnsignedByte

int readUnsignedByte()
                     throws IOException
Reads an unsigned byte.

The bit offset is set to zero before any data is read.

Specified by:
readUnsignedByte in interface DataInput
Returns:
The unsigned bytes value read as a Java int.
Throws:
EOFException - if the input stream is at its end.
IOException - if some general problem happens with accessing data.
See Also:
readByte(), readFully(byte[], int, int)

readShort

short readShort()
                throws IOException
Reads an signed 16-bit integer. If necessary, the value gets converted from the stream’s current byte order.

The bit offset is set to zero before any data is read.

Specified by:
readShort in interface DataInput
Returns:
The short value read
Throws:
EOFException - if the input stream ends before all two bytes were read.
IOException - if some general problem happens with accessing data.
See Also:
readUnsignedShort(), readChar(), readFully(short[], int, int)

readUnsignedShort

int readUnsignedShort()
                      throws IOException
Reads an unsigned 16-bit integer. If necessary, the value gets converted from the stream’s current byte order.

The bit offset is set to zero before any data is read.

This method does the same as readChar().

Specified by:
readUnsignedShort in interface DataInput
Returns:
The unsigned short value read as a Java int.
Throws:
EOFException - if the input stream ends before all two bytes were read.
IOException - if some general problem happens with accessing data.
See Also:
readShort(), readChar(), readFully(char[], int, int)

readChar

char readChar()
              throws IOException
Reads an unsigned 16-bit integer. If necessary, the value gets converted from the stream’s current byte order.

The bit offset is set to zero before any data is read.

This method does the same as readUnsignedShort().

Specified by:
readChar in interface DataInput
Returns:
The char value read
Throws:
EOFException - if the input stream ends before all two bytes were read.
IOException - if some general problem happens with accessing data.
See Also:
readFully(char[], int, int)

readInt

int readInt()
            throws IOException
Reads a signed 32-bit integer. If necessary, the value gets converted from the stream’s current byte order.

The bit offset is set to zero before any data is read.

Specified by:
readInt in interface DataInput
Returns:
The int value read
Throws:
EOFException - if the input stream ends before all four bytes were read.
IOException - if some general problem happens with accessing data.
See Also:
readUnsignedInt(), readFully(int[], int, int)

readUnsignedInt

long readUnsignedInt()
                     throws IOException
Reads an unsigned 32-bit integer. If necessary, the value gets converted from the stream’s current byte order.

The bit offset is set to zero before any data is read.

Throws:
EOFException - if the input stream ends before all four bytes were read.
IOException - if some general problem happens with accessing data.
See Also:
readInt(), readFully(int[], int, int)

readLong

long readLong()
              throws IOException
Reads a signed 64-bit integer. If necessary, the value gets converted from the stream’s current byte order.

The bit offset is set to zero before any data is read.

Specified by:
readLong in interface DataInput
Returns:
The long value read
Throws:
EOFException - if the input stream ends before all eight bytes were read.
IOException - if some general problem happens with accessing data.
See Also:
readFully(long[], int, int)

readFloat

float readFloat()
                throws IOException
Reads an IEEE 32-bit single-precision floating point number. If necessary, the value gets converted from the stream’s current byte order.

The bit offset is set to zero before any data is read.

Specified by:
readFloat in interface DataInput
Returns:
The float value read
Throws:
EOFException - if the input stream ends before all four bytes were read.
IOException - if some general problem happens with accessing data.
See Also:
readFully(float[], int, int)

readDouble

double readDouble()
                  throws IOException
Reads an IEEE 64-bit double-precision floating point number. If necessary, the value gets converted from the stream’s current byte order.

The bit offset is set to zero before any data is read.

Specified by:
readDouble in interface DataInput
Returns:
The double value read
Throws:
EOFException - if the input stream ends before all eight bytes were read.
IOException - if some general problem happens with accessing data.
See Also:
readFully(double[], int, int)

readLine

String readLine()
                throws IOException
Description copied from interface: DataInput
This method reads the next line of text data from an input stream. It operates by reading bytes and converting those bytes to 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.

Specified by:
readLine in interface DataInput
Returns:
The line read as a String
Throws:
IOException - If an error occurs

readUTF

String readUTF()
               throws IOException
Description copied from interface: DataInput
This method reads a 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.

Specified by:
readUTF in interface DataInput
Returns:
The String read
Throws:
EOFException - If end of file is reached before reading the String
UTFDataFormatException - If the data is not in UTF-8 format
IOException - If any other error occurs
See Also:
DataOutput.writeUTF(java.lang.String)

readFully

void readFully(byte[] b,
               int offset,
               int numBytes)
               throws IOException
Reads a sequence of signed 8-bit integers into a byte[] array.

The bit offset is set to zero before any data is read.

Specified by:
readFully in interface DataInput
Parameters:
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.
Throws:
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.
See Also:
readByte()

readFully

void readFully(byte[] b)
               throws IOException
Reads a sequence of signed 8-bit integers into a byte[] array.

The bit offset is set to zero before any data is read.

Specified by:
readFully in interface DataInput
Parameters:
b - an array for storing the read values.
Throws:
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.
See Also:
readByte(), readFully(byte[], int, int)

readFully

void readFully(short[] s,
               int offset,
               int numShorts)
               throws IOException
Reads a sequence of signed 16-bit integers into a 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.

Parameters:
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).
Throws:
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.
See Also:
readShort()

readFully

void readFully(char[] c,
               int offset,
               int numChars)
               throws IOException
Reads a sequence of unsigned 16-bit integers into a 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.

Parameters:
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).
Throws:
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.
See Also:
readChar()

readFully

void readFully(int[] i,
               int offset,
               int numInts)
               throws IOException
Reads a sequence of signed 32-bit integers into a 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.

Parameters:
i - an array for storing the read values.
offset - the index of the first element in i that will hold read data.
numLongs - the number of signed 32-bit integers to read (which is one fourth of the number of bytes).
Throws:
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.
See Also:
readInt()

readFully

void readFully(long[] l,
               int offset,
               int numLongs)
               throws IOException
Reads a sequence of signed 64-bit integers into a 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.

Parameters:
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).
Throws:
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.
See Also:
readLong()

readFully

void readFully(float[] f,
               int offset,
               int numFloats)
               throws IOException
Reads a sequence of IEEE 32-bit single-precision floating point numbers into a 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.

Parameters:
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).
Throws:
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.
See Also:
readFloat()

readFully

void readFully(double[] d,
               int offset,
               int numDoubles)
               throws IOException
Reads a sequence of IEEE 64-bit double-precision floating point numbers into a 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.

Parameters:
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).
Throws:
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.
See Also:
readDouble()

getStreamPosition

long getStreamPosition()
                       throws IOException
Throws:
IOException

getBitOffset

int getBitOffset()
                 throws IOException
Throws:
IOException

setBitOffset

void setBitOffset(int bitOffset)
                  throws IOException
Throws:
IOException

readBit

int readBit()
            throws IOException
Throws:
IOException

readBits

long readBits(int numBits)
              throws IOException
Throws:
IOException

length

long length()
            throws IOException
Throws:
IOException

skipBytes

int skipBytes(int numBytes)
              throws IOException
Description copied from interface: DataInput
This method skips and discards the specified number of bytes in an input stream. Note that this method may skip less than the requested number of bytes. The actual number of bytes skipped is returned. No bytes are skipped if a negative number is passed to this method.

Specified by:
skipBytes in interface DataInput
Parameters:
numBytes - The number of bytes to skip
Returns:
The number of bytes actually skipped, which will always be numBytes
Throws:
EOFException - If end of file is reached before all bytes can be skipped
IOException - If any other error occurs

skipBytes

long skipBytes(long numBytes)
               throws IOException
Throws:
IOException

seek

void seek(long pos)
          throws IOException
Throws:
IOException

mark

void mark()

reset

void reset()
           throws IOException
Throws:
IOException

flushBefore

void flushBefore(long pos)
                 throws IOException
Throws:
IOException

flush

void flush()
           throws IOException
Throws:
IOException

getFlushedPosition

long getFlushedPosition()

isCached

boolean isCached()

isCachedMemory

boolean isCachedMemory()

isCachedFile

boolean isCachedFile()

close

void close()
           throws IOException
Throws:
IOException