com.unister.semweb.drums.api
Class DRUMSInstantiator

java.lang.Object
  com.unister.semweb.drums.api.DRUMSInstantiator

public class DRUMSInstantiator
extends java.lang.Object

This class provides some factory methods to instantiate DRUMS by opening or creating a table.

Author:

Martin Nettling

Constructor Summary

DRUMSInstantiator()

Method Summary

static <Data extends AbstractKVStorable> DRUMS<Data>	createOrOpenTable(AbstractHashFunction hashFunction, DRUMSParameterSet<Data> gp) Creates or opens the table.
static <Data extends AbstractKVStorable> DRUMS<Data>	createTable(AbstractHashFunction hashFunction, DRUMSParameterSet<Data> gp) This method creates a new DRUMS object.
static <Data extends AbstractKVStorable> DRUMS<Data>	forceCreateTable(AbstractHashFunction hashFunction, DRUMSParameterSet<Data> gp) This method creates a new DRUMS object.
static <Data extends AbstractKVStorable> DRUMS<Data>	openTable(DRUMS.AccessMode accessMode, DRUMSParameterSet<Data> gp) Opens an existing table.

Methods inherited from class java.lang.Object

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

Constructor Detail

DRUMSInstantiator

public DRUMSInstantiator()

Method Detail

createTable

public static <Data extends AbstractKVStorable> DRUMS<Data> createTable(AbstractHashFunction hashFunction,
                                                                        DRUMSParameterSet<Data> gp)
                                                          throws java.io.IOException

This method creates a new DRUMS object.
If the directory in DRUMSParameterSet doesn't exist, it will be created.
If the directory in DRUMSParameterSet already exists an IOException will be thrown.

Parameters:

hashFunction - the hash function, decides where to store/search elements

gp - pointer to the DRUMSParameterSet used by the DRUMS to open

Returns:

new DRUMS-object

Throws:

java.io.IOException

forceCreateTable

public static <Data extends AbstractKVStorable> DRUMS<Data> forceCreateTable(AbstractHashFunction hashFunction,
                                                                             DRUMSParameterSet<Data> gp)
                                                               throws java.io.IOException

This method creates a new DRUMS object. The old DRUMS will be overwritten.
If the given directory doesn't exist, it will be created.

Parameters:

hashFunction - the hash function, decides where to store/search elements

gp - pointer to the DRUMSParameterSet used by the DRUMS to open

Returns:

new DRUMS-object

Throws:

java.io.IOException - if an error occurs while writing the configuration file

openTable

public static <Data extends AbstractKVStorable> DRUMS<Data> openTable(DRUMS.AccessMode accessMode,
                                                                      DRUMSParameterSet<Data> gp)
                                                        throws java.io.IOException

Opens an existing table.

Parameters:

accessMode - the AccessMode, how to access the DRUMS

gp - pointer to the DRUMSParameterSet used by the DRUMS to open

Returns:

the table

Throws:

java.io.IOException

createOrOpenTable

public static <Data extends AbstractKVStorable> DRUMS<Data> createOrOpenTable(AbstractHashFunction hashFunction,
                                                                              DRUMSParameterSet<Data> gp)
                                                                throws java.io.IOException

Creates or opens the table. If the directory doesn't exists it will be created.

Parameters:

hashFunction - the hash function, decides where to store/search elements

gp - pointer to the DRUMSParameterSet used by the DRUMS to open

Returns:

a DRUMS instance

Throws:

java.io.IOException

See Also:

#openTable(AccessMode, DRUMSParameterSet), createTable(AbstractHashFunction, DRUMSParameterSet)