| java.lang.Object
 jdbm.htree.HashNode
jdbm.htree.HashDirectory
| HashDirectory | | final class HashDirectory extends HashNode implements Externalizable(Code) | | Hashtable directory page.
author:
Alex Boisvert
version:
$Id: HashDirectory.java,v 1.5 2005/06/25 23:12:32 doomdark Exp $ |
| BIT_SIZE | | final static int BIT_SIZE(Code) | | Number of significant bits per directory level.
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| MAX_CHILDREN | | final static int MAX_CHILDREN(Code) | | Maximum number of children in a directory.
(Must be a power of 2 -- if you update this value, you must also
update BIT_SIZE and MAX_DEPTH.)
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| MAX_DEPTH | | final static int MAX_DEPTH(Code) | | Maximum number of levels (zero-based)
(4 * 8 bits = 32 bits, which is the size of an "int", and as
you know, hashcodes in Java are "ints")
|
| serialVersionUID | | final static long serialVersionUID(Code) | | |
| HashDirectory | | public HashDirectory()(Code) | | Public constructor used by serialization
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| HashDirectory | | HashDirectory(byte depth)(Code) | | Construct a HashDirectory
Parameters:
depth - Depth of this directory page. |
| get | | Object get(Object key) throws IOException(Code) | | Returns the value which is associated with the given key. Returns
null if there is not association for this key.
Parameters:
key - key whose associated value is to be returned |
| getRecid | | long getRecid()(Code) | | Get the record identifier used to load this hashtable.
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| hashMask | | int hashMask()(Code) | | Calculates the hashmask of this directory. The hashmask is the
bit mask applied to a hashcode to retain only bits that are
relevant to this directory level.
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| isEmpty | | boolean isEmpty()(Code) | | Returns whether or not this directory is empty. A directory
is empty when it no longer contains buckets or sub-directories.
|
| put | | Object put(Object key, Object value) throws IOException(Code) | | Associates the specified value with the specified key.
Parameters:
key - key with which the specified value is to be assocated.
Parameters:
value - value to be associated with the specified key. object which was previously associated with the given key,or null if no association existed. |
| remove | | Object remove(Object key) throws IOException(Code) | | Remove the value which is associated with the given key. If the
key does not exist, this method simply ignores the operation.
Parameters:
key - key whose associated value is to be removed object which was associated with the given key, ornull if no association existed with given key. |
| setPersistenceContext | | void setPersistenceContext(RecordManager recman, long recid)(Code) | | Sets persistence context. This method must be called before any
persistence-related operation.
Parameters:
recman - RecordManager which stores this directory
Parameters:
recid - Record id of this directory. |
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