Class java.io.RandomAccessFile
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  Class java.io.RandomAccessFile
java.lang.Object
   |
   +----java.io.RandomAccessFile
  -  public class RandomAccessFile
  
-  extends Object
  
-  implements DataOutput, DataInput
   
Random access files can be constructed from file descriptors, file 
names, or file objects.  This class provides a sense of security
by offering methods that allow specified mode accesses of 
read-only or read-write to files.
  
  -  
	RandomAccessFile(String, String)
   -  Creates a RandomAccessFile with the specified system dependent 
file name and the specified mode.
  
 -  
	RandomAccessFile(File, String)
   -  Creates a RandomAccessFile from a specified File object
and mode ("r" or "rw").
 
  
  -  
	close()
   -  Closes the file.
  
 -  
	getFD()
   -  Returns the opaque file descriptor object.
  
 -  
	getFilePointer()
   -  Returns the current location of the file pointer.
  
 -  
	length()
   -  Returns the length of the file.
  
 -  
	read()
   -  Reads a byte of data.
  
 -  
	read(byte[], int, int)
   -  Reads a sub array as a sequence of bytes.
  
 -  
	read(byte[])
   -  Reads data into an array of bytes.
  
 -  
	readBoolean()
   -  Reads a boolean.
  
 -  
	readByte()
   -  Reads a byte.
  
 -  
	readChar()
   -  Reads a 16 bit char.
  
 -  
	readDouble()
   -  Reads a 64 bit double.
  
 -  
	readFloat()
   -  Reads a 32 bit float.
  
 -  
	readFully(byte[])
   -  Reads bytes, blocking until all bytes are read.
  
 -  
	readFully(byte[], int, int)
   -  Reads bytes, blocking until all bytes are read.
  
 -  
	readInt()
   -  Reads a 32 bit int.
  
 -  
	readLine()
   -  Reads a line terminated by a '\n' or EOF.
  
 -  
	readLong()
   -  Reads a 64 bit long.
  
 -  
	readShort()
   -  Reads 16 bit short.
  
 -  
	readUTF()
   -  Reads a UTF formatted String.
  
 -  
	readUnsignedByte()
   -  Reads an unsigned 8 bit byte.
  
 -  
	readUnsignedShort()
   -  Reads 16 bit short.
  
 -  
	seek(long)
   -  Sets the file pointer to the specified absolute position.
  
 -  
	skipBytes(int)
   -  
  
 -  
	write(int)
   -  Writes a byte of data.
  
 -  
	write(byte[])
   -  Writes an array of bytes.
  
 -  
	write(byte[], int, int)
   -  Wrotes a sub array of bytes.
  
 -  
	writeBoolean(boolean)
   -  Writes a boolean.
  
 -  
	writeByte(int)
   -  Writes a byte.
  
 -  
	writeBytes(String)
   -  Writes a String as a sequence of bytes.
  
 -  
	writeChar(int)
   -  Writes a character.
  
 -  
	writeChars(String)
   -  Writes a String as a sequence of chars.
  
 -  
	writeDouble(double)
   -  
  
 -  
	writeFloat(float)
   -  
  
 -  
	writeInt(int)
   -  Writes an integer.
  
 -  
	writeLong(long)
   -  Writes a long.
  
 -  
	writeShort(int)
   -  Writes a short.
  
 -  
	writeUTF(String)
   -  Writes a String in UTF format.
 
  
RandomAccessFile
  public RandomAccessFile(String name,
                          String mode) throws IOException
  -  Creates a RandomAccessFile with the specified system dependent 
file name and the specified mode.
Mode "r" is for read-only and mode "rw" is for read+write.
  
    -  Parameters:
    
 -  name - the system dependent file name
    
-  mode - the access mode
    
  -  Throws: IOException
    
 -  If an I/O error has occurred.
  
 
 
RandomAccessFile
  public RandomAccessFile(File file,
                          String mode) throws IOException
  -  Creates a RandomAccessFile from a specified File object
and mode ("r" or "rw").
  
    -  Parameters:
    
 -  file - the file object
    
-  mode - the access mode
  
  
 
  
getFD
  public final FileDescriptor getFD() throws IOException
  -  Returns the opaque file descriptor object.
  
    -  Returns:
    
 -  the file descriptor.
  
 
 
read
  public int read() throws IOException
  -  Reads a byte of data. This method will block if no input is
available.
  
    -  Returns:
    
 -  the byte read, or -1 if the end of the
         stream is reached.
    
 -  Throws: IOException
    
 -  If an I/O error has occurred.
  
 
 
read
  public int read(byte b[],
                  int off,
                  int len) throws IOException
  -  Reads a sub array as a sequence of bytes.
  
    -  Parameters:
    
 -  b - the data to be written
    
-  off - the start offset in the data
    
-  len - the number of bytes that are written
    
   -  Throws: IOException
    
 -  If an I/O error has occurred.
  
 
 
read
  public int read(byte b[]) throws IOException
  -  Reads data into an array of bytes.  This method blocks
until some input is available.
  
    -  Returns:
    
 -  the actual number of bytes read, -1 is
         returned when the end of the stream is reached.
    
 -  Throws: IOException
    
 -  If an I/O error has occurred.
  
 
 
readFully
  public final void readFully(byte b[]) throws IOException
  -  Reads bytes, blocking until all bytes are read.
  
    -  Parameters:
    
 -  b - the buffer into which the data is read
    
 -  Returns:
    
 -  the actual number of bytes read, -1 is
		returned when the end of the stream is reached.
    
 -  Throws: IOException
    
 -  If an I/O error has occurred.
  
 
 
readFully
  public final void readFully(byte b[],
                              int off,
                              int len) throws IOException
  -  Reads bytes, blocking until all bytes are read.
  
    -  Parameters:
    
 -  b - the buffer into which the data is read
    
-  off - the start offset of the data
    
-  len - the maximum number of bytes read
    
   -  Returns:
    
 -  the actual number of bytes read, -1 is
		returned when the end of the stream is reached.
    
 -  Throws: IOException
    
 -  If an I/O error has occurred.
  
 
 
skipBytes
  public int skipBytes(int n) throws IOException
write
  public void write(int b) throws IOException
  -  Writes a byte of data. This method will block until the byte
is actually written.
  
    -  Parameters:
    
 -  b - the byte to be written
    
 -  Throws: IOException
    
 -  If an I/O error has occurred.
  
 
 
write
  public void write(byte b[]) throws IOException
  -  Writes an array of bytes. Will block until the bytes
are actually written.
  
    -  Parameters:
    
 -  b - the data to be written
    
 -  Throws: IOException
    
 -  If an I/O error has occurred.
  
 
 
write
  public void write(byte b[],
                    int off,
                    int len) throws IOException
  -  Wrotes a sub array of bytes.
  
    -  Parameters:
    
 -  b - the data to be written
    
-  off - the start offset in the data
    
-  len - the number of bytes that are written
    
   -  Throws: IOException
    
 -  If an I/O error has occurred.
  
 
 
getFilePointer
  public long getFilePointer() throws IOException
  -  Returns the current location of the file pointer.
 
seek
  public void seek(long pos) throws IOException
  -  Sets the file pointer to the specified absolute position.
  
    -  Parameters:
    
 -  pos - the absolute position
  
 
 
length
  public long length() throws IOException
  -  Returns the length of the file.
 
close
  public void close() throws IOException
  -  Closes the file.
  
    -  Throws: IOException
    
 -  If an I/O error has occurred.
  
 
 
readBoolean
  public final boolean readBoolean() throws IOException
  -  Reads a boolean.
 
readByte
  public final byte readByte() throws IOException
  -  Reads a byte.
 
readUnsignedByte
  public final int readUnsignedByte() throws IOException
  -  Reads an unsigned 8 bit byte.
  
    -  Returns:
    
 -  the 8 bit byte read.
  
 
 
readShort
  public final short readShort() throws IOException
  -  Reads 16 bit short.
  
    -  Returns:
    
 -  the read 16 bit short.
  
 
 
readUnsignedShort
  public final int readUnsignedShort() throws IOException
  -  Reads 16 bit short.
  
    -  Returns:
    
 -  the read 16 bit short.
  
 
 
readChar
  public final char readChar() throws IOException
  -  Reads a 16 bit char.
  
    -  Returns:
    
 -  the read 16 bit char.
  
 
 
readInt
  public final int readInt() throws IOException
  -  Reads a 32 bit int.
  
    -  Returns:
    
 -  the read 32 bit integer.
  
 
 
readLong
  public final long readLong() throws IOException
  -  Reads a 64 bit long.
  
    -  Returns:
    
 -  the read 64 bit long.
  
 
 
readFloat
  public final float readFloat() throws IOException
  -  Reads a 32 bit float.
  
    -  Returns:
    
 -  the read 32 bit float.
  
 
 
readDouble
  public final double readDouble() throws IOException
  -  Reads a 64 bit double.
  
    -  Returns:
    
 -  the read 64 bit double.
  
 
 
readLine
  public final String readLine() throws IOException
  -  Reads a line terminated by a '\n' or EOF.
 
readUTF
  public final String readUTF() throws IOException
  -  Reads a UTF formatted String.
 
writeBoolean
  public final void writeBoolean(boolean v) throws IOException
  -  Writes a boolean.
  
    -  Parameters:
    
 -  v - the boolean value
  
 
 
writeByte
  public final void writeByte(int v) throws IOException
  -  Writes a byte.
  
    -  Parameters:
    
 -  v - the byte
  
 
 
writeShort
  public final void writeShort(int v) throws IOException
  -  Writes a short.
  
    -  Parameters:
    
 -  v - the short
  
 
 
writeChar
  public final void writeChar(int v) throws IOException
  -  Writes a character.
  
    -  Parameters:
    
 -  v - the char
  
 
 
writeInt
  public final void writeInt(int v) throws IOException
  -  Writes an integer.
  
    -  Parameters:
    
 -  v - the integer
  
 
 
writeLong
  public final void writeLong(long v) throws IOException
  -  Writes a long.
  
    -  Parameters:
    
 -  v - the long
  
 
 
writeFloat
  public final void writeFloat(float v) throws IOException
writeDouble
  public final void writeDouble(double v) throws IOException
writeBytes
  public final void writeBytes(String s) throws IOException
  -  Writes a String as a sequence of bytes.
  
    -  Parameters:
    
 -  s - the String
  
 
 
writeChars
  public final void writeChars(String s) throws IOException
  -  Writes a String as a sequence of chars.
  
    -  Parameters:
    
 -  s - the String
  
 
 
writeUTF
  public final void writeUTF(String str) throws IOException
  -  Writes a String in UTF format.
  
    -  Parameters:
    
 -  str - the String
  
 
 
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