index
Class BucketScan

java.lang.Object
  index.BucketScan

All Implemented Interfaces:

GlobalConst

public class BucketScan
extends java.lang.Object
implements GlobalConst

Scans an entire hash index file, bucket by bucket; created only through the openScan() method in the HashIndex class.

Field Summary

Fields inherited from interface global.GlobalConst

EMPTY_SLOT, FIRST_PAGEID, INVALID_PAGEID, MAX_COLSIZE, MAX_TUPSIZE, NAME_MAXLEN, PAGE_SIZE, PIN_DISKIO, PIN_MEMCPY, UNPIN_CLEAN, UNPIN_DIRTY

Method Summary

void	close() Closes the index scan, releasing any pinned pages.
SearchKey	getLastKey() Gets the key of the last RID returned.
RID	getNext() Gets the next entry's record in the index scan.
int	getNextHash() Returns the hash value for the bucket containing the next RID, or maximum number of buckets if none.
boolean	hasNext() Returns true if there are more entries to scan, false otherwise.

Methods inherited from class java.lang.Object

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

Method Detail

close

public void close()

Closes the index scan, releasing any pinned pages.

hasNext

public boolean hasNext()

Returns true if there are more entries to scan, false otherwise.

getNext

public RID getNext()

Gets the next entry's record in the index scan.

Throws:

java.lang.IllegalStateException - if the scan has no more entries

getLastKey

public SearchKey getLastKey()

Gets the key of the last RID returned.

getNextHash

public int getNextHash()

Returns the hash value for the bucket containing the next RID, or maximum number of buckets if none.