org.basex.io
Class TableAccess

java.lang.Object
  extended by org.basex.io.TableAccess
Direct Known Subclasses:
TableDiskAccess, TableMemAccess

public abstract class TableAccess
extends java.lang.Object

This abstract class defines the methods for accessing the database table representation.

Author:
Workgroup DBIS, University of Konstanz 2005-08, ISC License, Christian Gruen

Constructor Summary
TableAccess()
           
 
Method Summary
abstract  void close()
          Closes the table access.
abstract  void delete(int pre, int nr)
          Delete a range of entries.
abstract  void flush()
          Flushes the table contents.
abstract  void insert(int pre, byte[] entries)
          Insert entries.
abstract  int read1(int p, int o)
          Reads a byte from the specified position and returns it as integer.
abstract  int read2(int p, int o)
          Reads a short value from the specified position and returns it as integer.
abstract  int read4(int p, int o)
          Reads an integer value from the specified position.
abstract  long read5(int p, int o)
          Reads an integer value from the specified position.
abstract  void write1(int p, int o, int v)
          Writes a byte to the specified position.
abstract  void write2(int p, int o, int v)
          Writes 2 bytes to the specified position.
abstract  void write4(int p, int o, int v)
          Writes an integer value to the specified position.
abstract  void write5(int p, int o, long v)
          Writes a 5-byte value to the specified position.
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

TableAccess

public TableAccess()
Method Detail

read1

public abstract int read1(int p,
                          int o)
Reads a byte from the specified position and returns it as integer.

Parameters:
p - pre value
o - offset
Returns:
integer value

read2

public abstract int read2(int p,
                          int o)
Reads a short value from the specified position and returns it as integer.

Parameters:
p - pre value
o - offset
Returns:
integer value

read4

public abstract int read4(int p,
                          int o)
Reads an integer value from the specified position.

Parameters:
p - pre value
o - offset
Returns:
integer value

read5

public abstract long read5(int p,
                           int o)
Reads an integer value from the specified position.

Parameters:
p - pre value
o - offset
Returns:
integer value

write1

public abstract void write1(int p,
                            int o,
                            int v)
Writes a byte to the specified position.

Parameters:
p - pre value
o - offset
v - value to be written

write2

public abstract void write2(int p,
                            int o,
                            int v)
Writes 2 bytes to the specified position.

Parameters:
p - pre value
o - offset
v - value to be written

write4

public abstract void write4(int p,
                            int o,
                            int v)
Writes an integer value to the specified position.

Parameters:
p - pre value
o - offset
v - value to be written

write5

public abstract void write5(int p,
                            int o,
                            long v)
Writes a 5-byte value to the specified position.

Parameters:
p - pre value
o - offset
v - value to be written

delete

public abstract void delete(int pre,
                            int nr)
Delete a range of entries.

Parameters:
pre - pre value of the first node to delete
nr - number of entries to be deleted

insert

public abstract void insert(int pre,
                            byte[] entries)
Insert entries.

Parameters:
pre - pre value of node to insert after
entries - array of bytes containing the entries to insert

flush

public abstract void flush()
                    throws java.io.IOException
Flushes the table contents.

Throws:
java.io.IOException - in case of write errors

close

public abstract void close()
                    throws java.io.IOException
Closes the table access.

Throws:
java.io.IOException - in case of write errors