com.twelvemonkeys.io
Class LittleEndianRandomAccessFile

java.lang.Object
  com.twelvemonkeys.io.LittleEndianRandomAccessFile

All Implemented Interfaces:

DataInput, DataOutput

public class LittleEndianRandomAccessFile
extends Object
implements DataInput, DataOutput

A replacement for RandomAccessFile that is capable of reading and writing data in little endian byte order.

Warning: The DataInput and DataOutput interfaces specifies big endian byte order in their documentation. This means that this class is, strictly speaking, not a proper implementation. However, I don't see a reason for the these interfaces to specify the byte order of their underlying representations.

Version:

$Id: //depot/branches/personal/haraldk/twelvemonkeys/release-2/twelvemonkeys-core/src/main/java/com/twelvemonkeys/io/LittleEndianRandomAccessFile.java#1 $

Author:

Elliotte Rusty Harold, Harald Kuhr, last modified by $Author: haku $

See Also:

LittleEndianDataInputStream, LittleEndianDataOutputStream, RandomAccessFile, DataInput, DataOutput

Constructor Summary

LittleEndianRandomAccessFile(File pFile, String pMode)

LittleEndianRandomAccessFile(String pName, String pMode)

Method Summary

void	close()
FileChannel	getChannel()
FileDescriptor	getFD()
long	getFilePointer()
long	length()
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)
boolean	readBoolean() Reads a boolean from the underlying input stream by reading a single byte.
byte	readByte() Reads a signed byte from the underlying input stream with value between -128 and 127
char	readChar() Reads a two byte Unicode char from the underlying input stream in little endian order, low byte first.
double	readDouble()
float	readFloat()
void	readFully(byte[] b)
void	readFully(byte[] b, int off, int len)
int	readInt() Reads a four byte signed int from the underlying input stream in little endian order, low byte first.
String	readLine()
long	readLong() Reads an eight byte signed int from the underlying input stream in little endian order, low byte first.
short	readShort() Reads a two byte signed short from the underlying input stream in little endian order, low byte first.
int	readUnsignedByte() Reads an unsigned byte from the underlying input stream with value between 0 and 255
int	readUnsignedShort() Reads a two byte unsigned short from the underlying input stream in little endian order, low byte first.
String	readUTF() Reads a string of no more than 65,535 characters from the underlying input stream using UTF-8 encoding.
void	seek(long pos) Sets the file-pointer offset, measured from the beginning of this file, at which the next read or write occurs.
void	setLength(long newLength)
int	skipBytes(int n)
void	write(byte[] b)
void	write(byte[] b, int off, int len)
void	write(int b)
void	writeBoolean(boolean pBoolean) Writes a boolean to the underlying output stream as a single byte.
void	writeByte(int pByte) Writes out a byte to the underlying output stream
void	writeBytes(String pString) Writes a string to the underlying output stream as a sequence of bytes.
void	writeChar(int pChar) Writes a two byte char to the underlying output stream in little endian order, low byte first.
void	writeChars(String pString) Writes a string to the underlying output stream as a sequence of characters.
void	writeDouble(double d) Writes an 8 byte Java double to the underlying output stream in little endian order.
void	writeFloat(float f) Writes a 4 byte Java float to the underlying output stream in little endian order.
void	writeInt(int pInt) Writes a four-byte int to the underlying output stream in little endian order, low byte first, high byte last
void	writeLong(long pLong) Writes an eight-byte long to the underlying output stream in little endian order, low byte first, high byte last
void	writeShort(int pShort) Writes a two byte short to the underlying output stream in little endian order, low byte first.
void	writeUTF(String pString) Writes a string of no more than 65,535 characters to the underlying output stream using UTF-8 encoding.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

LittleEndianRandomAccessFile

public LittleEndianRandomAccessFile(String pName,
                                    String pMode)
                             throws FileNotFoundException

Throws:

FileNotFoundException

LittleEndianRandomAccessFile

public LittleEndianRandomAccessFile(File pFile,
                                    String pMode)
                             throws FileNotFoundException

Throws:

FileNotFoundException

Method Detail

close

public void close()
           throws IOException

Throws:

IOException

getChannel

public FileChannel getChannel()

getFD

public FileDescriptor getFD()
                     throws IOException

Throws:

IOException

getFilePointer

public long getFilePointer()
                    throws IOException

Throws:

IOException

length

public long length()
            throws IOException

Throws:

IOException

read

public int read()
         throws IOException

Throws:

IOException

read

public int read(byte[] b)
         throws IOException

Throws:

IOException

read

public int read(byte[] b,
                int off,
                int len)
         throws IOException

Throws:

IOException

readFully

public void readFully(byte[] b)
               throws IOException

Specified by:

readFully in interface DataInput

Throws:

IOException

readFully

public void readFully(byte[] b,
                      int off,
                      int len)
               throws IOException

Specified by:

readFully in interface DataInput

Throws:

IOException

readLine

public String readLine()
                throws IOException

Specified by:

readLine in interface DataInput

Throws:

IOException

readBoolean

public boolean readBoolean()
                    throws IOException

Reads a boolean from the underlying input stream by reading a single byte. If the byte is zero, false is returned. If the byte is positive, true is returned.

Specified by:

readBoolean in interface DataInput

Returns:

the boolean value read.

Throws:

EOFException - if the end of the underlying input stream has been reached

IOException - if the underlying stream throws an IOException.

readByte

public byte readByte()
              throws IOException

Reads a signed byte from the underlying input stream with value between -128 and 127

Specified by:

readByte in interface DataInput

Returns:

the byte value read.

Throws:

EOFException - if the end of the underlying input stream has been reached

IOException - if the underlying stream throws an IOException.

readUnsignedByte

public int readUnsignedByte()
                     throws IOException

Reads an unsigned byte from the underlying input stream with value between 0 and 255

Specified by:

readUnsignedByte in interface DataInput

Returns:

the byte value read.

Throws:

EOFException - if the end of the underlying input stream has been reached

IOException - if the underlying stream throws an IOException.

readShort

public short readShort()
                throws IOException

Reads a two byte signed short from the underlying input stream in little endian order, low byte first.

Specified by:

readShort in interface DataInput

Returns:

the short read.

Throws:

EOFException - if the end of the underlying input stream has been reached

IOException - if the underlying stream throws an IOException.

readUnsignedShort

public int readUnsignedShort()
                      throws IOException

Reads a two byte unsigned short from the underlying input stream in little endian order, low byte first.

Specified by:

readUnsignedShort in interface DataInput

Returns:

the int value of the unsigned short read.

Throws:

EOFException - if the end of the underlying input stream has been reached

IOException - if the underlying stream throws an IOException.

readChar

public char readChar()
              throws IOException

Reads a two byte Unicode char from the underlying input stream in little endian order, low byte first.

Specified by:

readChar in interface DataInput

Returns:

the int value of the unsigned short read.

Throws:

EOFException - if the end of the underlying input stream has been reached

IOException - if the underlying stream throws an IOException.

readInt

public int readInt()
            throws IOException

Reads a four byte signed int from the underlying input stream in little endian order, low byte first.

Specified by:

readInt in interface DataInput

Returns:

the int read.

Throws:

EOFException - if the end of the underlying input stream has been reached

IOException - if the underlying stream throws an IOException.

readLong

public long readLong()
              throws IOException

Reads an eight byte signed int from the underlying input stream in little endian order, low byte first.

Specified by:

readLong in interface DataInput

Returns:

the int read.

Throws:

EOFException - if the end of the underlying input stream has been reached

IOException - if the underlying stream throws an IOException.

readUTF

public String readUTF()
               throws IOException

Reads a string of no more than 65,535 characters from the underlying input stream using UTF-8 encoding. This method first reads a two byte short in big endian order as required by the UTF-8 specification. This gives the number of bytes in the UTF-8 encoded version of the string. Next this many bytes are read and decoded as UTF-8 encoded characters.

Specified by:

readUTF in interface DataInput

Returns:

the decoded string

Throws:

UTFDataFormatException - if the string cannot be decoded

IOException - if the underlying stream throws an IOException.

readDouble

public final double readDouble()
                        throws IOException

Specified by:

readDouble in interface DataInput

Returns:

the next eight bytes of this input stream, interpreted as a little endian double.

Throws:

EOFException - if end of stream occurs before eight bytes have been read.

IOException - if an I/O error occurs.

readFloat

public final float readFloat()
                      throws IOException

Specified by:

readFloat in interface DataInput

Returns:

the next four bytes of this input stream, interpreted as a little endian int.

Throws:

EOFException - if end of stream occurs before four bytes have been read.

IOException - if an I/O error occurs.

seek

public void seek(long pos)
          throws IOException

Sets the file-pointer offset, measured from the beginning of this file, at which the next read or write occurs. The offset may be set beyond the end of the file. Setting the offset beyond the end of the file does not change the file length. The file length will change only by writing after the offset has been set beyond the end of the file.

Parameters:

pos - the offset position, measured in bytes from the beginning of the file, at which to set the file pointer.

Throws:

IOException - if pos is less than 0 or if an I/O error occurs.

setLength

public void setLength(long newLength)
               throws IOException

Throws:

IOException

skipBytes

public int skipBytes(int n)
              throws IOException

Specified by:

skipBytes in interface DataInput

Throws:

IOException

write

public void write(byte[] b)
           throws IOException

Specified by:

write in interface DataOutput

Throws:

IOException

write

public void write(byte[] b,
                  int off,
                  int len)
           throws IOException

Specified by:

write in interface DataOutput

Throws:

IOException

write

public void write(int b)
           throws IOException

Specified by:

write in interface DataOutput

Throws:

IOException

writeBoolean

public void writeBoolean(boolean pBoolean)
                  throws IOException

Writes a boolean to the underlying output stream as a single byte. If the argument is true, the byte value 1 is written. If the argument is false, the byte value 0 in written.

Specified by:

writeBoolean in interface DataOutput

Parameters:

pBoolean - the boolean value to be written.

Throws:

IOException - if the underlying stream throws an IOException.

writeByte

public void writeByte(int pByte)
               throws IOException

Writes out a byte to the underlying output stream

Specified by:

writeByte in interface DataOutput

Parameters:

pByte - the byte value to be written.

Throws:

IOException - if the underlying stream throws an IOException.

writeShort

public void writeShort(int pShort)
                throws IOException

Writes a two byte short to the underlying output stream in little endian order, low byte first.

Specified by:

writeShort in interface DataOutput

Parameters:

pShort - the short to be written.

Throws:

IOException - if the underlying stream throws an IOException.

writeChar

public void writeChar(int pChar)
               throws IOException

Writes a two byte char to the underlying output stream in little endian order, low byte first.

Specified by:

writeChar in interface DataOutput

Parameters:

pChar - the char value to be written.

Throws:

IOException - if the underlying stream throws an IOException.

writeInt

public void writeInt(int pInt)
              throws IOException

Writes a four-byte int to the underlying output stream in little endian order, low byte first, high byte last

Specified by:

writeInt in interface DataOutput

Parameters:

pInt - the int to be written.

Throws:

IOException - if the underlying stream throws an IOException.

writeLong

public void writeLong(long pLong)
               throws IOException

Writes an eight-byte long to the underlying output stream in little endian order, low byte first, high byte last

Specified by:

writeLong in interface DataOutput

Parameters:

pLong - the long to be written.

Throws:

IOException - if the underlying stream throws an IOException.

writeFloat

public final void writeFloat(float f)
                      throws IOException

Writes a 4 byte Java float to the underlying output stream in little endian order.

Specified by:

writeFloat in interface DataOutput

Parameters:

f - the float value to be written.

Throws:

IOException - if an I/O error occurs.

writeDouble

public final void writeDouble(double d)
                       throws IOException

Writes an 8 byte Java double to the underlying output stream in little endian order.

Specified by:

writeDouble in interface DataOutput

Parameters:

d - the double value to be written.

Throws:

IOException - if an I/O error occurs.

writeBytes

public void writeBytes(String pString)
                throws IOException

Writes a string to the underlying output stream as a sequence of bytes. Each character is written to the data output stream as if by the writeByte() method.

Specified by:

writeBytes in interface DataOutput

Parameters:

pString - the String value to be written.

Throws:

IOException - if the underlying stream throws an IOException.

See Also:

writeByte(int), file

writeChars

public void writeChars(String pString)
                throws IOException

Writes a string to the underlying output stream as a sequence of characters. Each character is written to the data output stream as if by the writeChar method.

Specified by:

writeChars in interface DataOutput

Parameters:

pString - a String value to be written.

Throws:

IOException - if the underlying stream throws an IOException.

See Also:

writeChar(int), file

writeUTF

public void writeUTF(String pString)
              throws IOException

Writes a string of no more than 65,535 characters to the underlying output stream using UTF-8 encoding. This method first writes a two byte short in big endian order as required by the UTF-8 specification. This gives the number of bytes in the UTF-8 encoded version of the string, not the number of characters in the string. Next each character of the string is written using the UTF-8 encoding for the character.

Specified by:

writeUTF in interface DataOutput

Parameters:

pString - the string to be written.

Throws:

UTFDataFormatException - if the string is longer than 65,535 characters.

IOException - if the underlying stream throws an IOException.