org.unict.ing.pds.dhtdb.datamanager.lightBeans

Class QuerySessionBean

java.lang.Object

org.unict.ing.pds.dhtdb.datamanager.lightBeans.QuerySessionBean

All Implemented Interfaces:

QuerySessionBeanLocal

public class QuerySessionBean
extends Object
implements QuerySessionBeanLocal

This is responsible for the Query on the distributed database over LIGHT indexing

Field Summary

Fields

Modifier and Type	Field and Description
private LightSessionBeanLocal	lightSessionBean
private LookupSessionBeanLocal	lookupSessionBean

Constructor Summary

Constructors

Constructor and Description
QuerySessionBean()

Method Summary

Modifier and Type	Method and Description
List<GenericValue>	getRangeQueryDatas(Range range) This method can be called outside the Bean to make the query and get the Datas associated
private Set<Bucket>	rangeQuery(Range range, int maxLength) Creates the Set of Bucket that could store the Records associated with the Range given (the query)
private Set<Bucket>	recursiveForward(Range initialRange, Range range, Label region, Set<Bucket> subRangesSet, int maxLength) Recursive function that search the neighbours Bucket leaves that match with the Range of the query running

Methods inherited from class java.lang.Object

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

Field Detail

lightSessionBean

private LightSessionBeanLocal lightSessionBean

lookupSessionBean

private LookupSessionBeanLocal lookupSessionBean

Constructor Detail

QuerySessionBean

public QuerySessionBean()

Method Detail

recursiveForward

private Set<Bucket> recursiveForward(Range initialRange,
                                     Range range,
                                     Label region,
                                     Set<Bucket> subRangesSet,
                                     int maxLength)

Recursive function that search the neighbours Bucket leaves that match with the Range of the query running

Parameters:

initialRange - the initial range of the query |

range - the range after intersection with a neighbour's one, the methods exits when this range is empty |

region - the first the lowest common ancestor, after the branchNode of a neighbour |

subRangesSet - a reference to the Set to be returned, filled across the recursions |

maxLength - a safety parameter to avoid infinite recursion: the methods will not use a label with length greater than maxLength (the tree height) |

Returns:

| a Set of Bucket that could store the associated datas

rangeQuery

private Set<Bucket> rangeQuery(Range range,
                               int maxLength)

Creates the Set of Bucket that could store the Records associated with the Range given (the query)

Parameters:

range - |

maxLength - |

Returns:

|

getRangeQueryDatas

public List<GenericValue> getRangeQueryDatas(Range range)

This method can be called outside the Bean to make the query and get the Datas associated

Specified by:

getRangeQueryDatas in interface QuerySessionBeanLocal

Parameters:

range - |

Returns:

| the result datas of the query given