iitb.con.query
Class ItemReader<T>

java.lang.Object
  iitb.con.query.ItemReader<T>

public class ItemReader<T>
extends java.lang.Object

InstanceReader reads an instance item from the concept-net.

Constructor Summary

ItemReader(java.lang.String fileName, ItemSerializer<T> itemSerializer)
Constructs the InstanceReader with respective file and item serializer

Method Summary

void	close() Closes the item file
T	getItem(long location, int length) Retrieves and deserialize the item from the file
java.lang.Object	getItemAttributeValue(long location, int length, java.lang.String name) Retrieves and deserialize the item from the file

Methods inherited from class java.lang.Object

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

Constructor Detail

ItemReader

public ItemReader(java.lang.String fileName,
                  ItemSerializer<T> itemSerializer)
           throws java.io.FileNotFoundException,
                  java.io.IOException

Constructs the InstanceReader with respective file and item serializer

Parameters:

fileName - file name of the where the item exists

itemSerializer - item serializer to decode the item

Throws:

java.io.FileNotFoundException - if file does not found

java.io.IOException - if file operation fails

Method Detail

close

public void close()
           throws java.io.IOException

Closes the item file

Throws:

java.io.IOException - if file operation fails

getItem

public T getItem(long location,
                 int length)
          throws java.io.IOException

Retrieves and deserialize the item from the file

Parameters:

location - item location

length - item length

Returns:

item (the type of item depends the Item Serializer)

Throws:

java.io.IOException

getItemAttributeValue

public java.lang.Object getItemAttributeValue(long location,
                                              int length,
                                              java.lang.String name)
                                       throws java.io.IOException

Retrieves and deserialize the item from the file

Parameters:

location - item location

length - item length

name - attribute name

Returns:

attribute's value as Object

Throws:

java.io.IOException