org.rutil.collection.trie
Class FileDataSourceCallback<VALUE_TYPE extends java.io.Serializable>

java.lang.Object
  org.rutil.collection.trie.FileDataSourceCallback<VALUE_TYPE>

All Implemented Interfaces:

java.io.Serializable, DataSourceCallback<VALUE_TYPE>

public class FileDataSourceCallback<VALUE_TYPE extends java.io.Serializable>
extends java.lang.Object
implements DataSourceCallback<VALUE_TYPE>, java.io.Serializable

Author:

mohan

See Also:

Serialized Form

Constructor Summary

FileDataSourceCallback(SerializableObjectsFile<VALUE_TYPE> valueFile)

Method Summary

boolean	exists(long key) Check if the key exists
VALUE_TYPE	fetch(long key) Fetch the value associated with the given key.
long	save(VALUE_TYPE value) Saves the given value to the backing datastore and returns a unique key to reference this value.

Methods inherited from class java.lang.Object

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

Constructor Detail

FileDataSourceCallback

public FileDataSourceCallback(SerializableObjectsFile<VALUE_TYPE> valueFile)

Method Detail

save

public long save(VALUE_TYPE value)
          throws java.lang.NullPointerException

Description copied from interface: DataSourceCallback

Saves the given value to the backing datastore and returns a unique key to reference this value.

Specified by:

save in interface DataSourceCallback<VALUE_TYPE extends java.io.Serializable>

Returns:

unique key that maps to the value

Throws:

java.lang.NullPointerException

fetch

public VALUE_TYPE fetch(long key)

Description copied from interface: DataSourceCallback

Fetch the value associated with the given key.

Specified by:

fetch in interface DataSourceCallback<VALUE_TYPE extends java.io.Serializable>

Returns:

value if a mapping exists for the given key or null

exists

public boolean exists(long key)

Description copied from interface: DataSourceCallback

Check if the key exists

Specified by:

exists in interface DataSourceCallback<VALUE_TYPE extends java.io.Serializable>

Returns:

true if the key exists, false otherwise.