org.apache.directory.server.xdbm

Interface Table<K,V>

All Known Subinterfaces:

MasterTable

All Known Implementing Classes:

AbstractTable, AvlMasterTable, AvlTable

public interface Table<K,V>

A wrapper interface around BTree implementations used to abstract away implementation details.

Author:

Apache Directory Project

Method Summary

Modifier and Type	Method and Description
void	close(org.apache.directory.server.core.api.partition.PartitionTxn transaction) Closes the underlying Db of this Table.
long	count(org.apache.directory.server.core.api.partition.PartitionTxn transaction) Gets the count of the number of Tuples in this Table.
long	count(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key) Gets the count of the number of records in this Table with a specific key: returns the number of duplicates for a key.
org.apache.directory.api.ldap.model.cursor.Cursor<org.apache.directory.api.ldap.model.cursor.Tuple<K,V>>	cursor() Creates a Cursor that traverses Tuples in a Table.
org.apache.directory.api.ldap.model.cursor.Cursor<org.apache.directory.api.ldap.model.cursor.Tuple<K,V>>	cursor(org.apache.directory.server.core.api.partition.PartitionTxn partitionTxn, K key) Creates a Cursor that traverses Table Tuples for the same key.
V	get(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key) Gets the value of a record by key if the key exists.
Comparator<K>	getKeyComparator() Gets the key comparator used by this Table: may be null if this Table was not initialized with one.
String	getName() Gets the name of this Table.
Comparator<V>	getValueComparator() Gets the value comparator used by this Table: may be null if this Table was not initialized with one.
long	greaterThanCount(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key) Gets the number of records greater than or equal to a key value.
boolean	has(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key) Checks to see if this table has one or more tuples with a specific key: this is exactly the same as a get call with a check to see if the returned value is null or not.
boolean	has(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key, V value) Checks to see if this table has a key with a specific value.
boolean	hasGreaterOrEqual(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key) Checks to see if this table has a record with a key greater than or equal to the key argument.
boolean	hasGreaterOrEqual(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key, V val) Checks to see if this table has a Tuple with a key equal to the key argument, yet with a value greater than or equal to the value argument provided.
boolean	hasLessOrEqual(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key) Checks to see if this table has a record with a key less than or equal to the key argument.
boolean	hasLessOrEqual(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key, V val) Checks to see if this table has a Tuple with a key equal to the key argument, yet with a value less than or equal to the value argument provided.
boolean	isDupsEnabled() Checks to see if this Table has allows for duplicate keys (a.k.a.
long	lessThanCount(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key) Gets the number of records less than or equal to a key value.
void	put(org.apache.directory.server.core.api.partition.PartitionTxn writeTransaction, K key, V value) Puts a record into this Table.
void	remove(org.apache.directory.server.core.api.partition.PartitionTxn writeTransaction, K key) Removes all records with a specified key from this Table.
void	remove(org.apache.directory.server.core.api.partition.PartitionTxn writeTransaction, K key, V value) Removes a single key value pair with a specified key and value from this Table.
org.apache.directory.api.ldap.model.cursor.Cursor<V>	valueCursor(org.apache.directory.server.core.api.partition.PartitionTxn transaction, K key) Creates a Cursor that traverses Table values for the same key.

Method Detail

getKeyComparator

Comparator<K> getKeyComparator()

Gets the key comparator used by this Table: may be null if this Table was not initialized with one.

Returns:

the key comparator or null if this Table was not created with one.

getValueComparator

Comparator<V> getValueComparator()

Gets the value comparator used by this Table: may be null if this Table was not initialized with one.

Returns:

the value comparator or null if this Table was not created with one.

getName

String getName()

Gets the name of this Table.

Returns:

the name

isDupsEnabled

boolean isDupsEnabled()

Checks to see if this Table has allows for duplicate keys (a.k.a. multiple values for the same key).

Returns:

true if duplicate keys are enabled, false otherwise

has

boolean has(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
            K key)
     throws org.apache.directory.api.ldap.model.exception.LdapException

Checks to see if this table has one or more tuples with a specific key: this is exactly the same as a get call with a check to see if the returned value is null or not.

Parameters:

transaction - The transaction we are running in

key - the Object of the key to check for

Returns:

true if the key exists, false otherwise

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying Db

has

boolean has(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
            K key,
            V value)
     throws org.apache.directory.api.ldap.model.exception.LdapException

Checks to see if this table has a key with a specific value.

Parameters:

transaction - The transaction we are running in

key - the key to check for

value - the value to check for

Returns:

true if a record with the key and value exists, false otherwise

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying Db

hasGreaterOrEqual

boolean hasGreaterOrEqual(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
                          K key)
                   throws org.apache.directory.api.ldap.model.exception.LdapException

Checks to see if this table has a record with a key greater than or equal to the key argument. The key argument need not exist for this call to return true. The underlying database must sort keys based on a key comparator because this method depends on key ordering.

Parameters:

transaction - The transaction we are running in

key - the key to compare keys to

Returns:

true if a Tuple with a key greater than or equal to the key argument exists, false otherwise

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying Db

hasLessOrEqual

boolean hasLessOrEqual(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
                       K key)
                throws org.apache.directory.api.ldap.model.exception.LdapException

Checks to see if this table has a record with a key less than or equal to the key argument. The key argument need not exist for this call to return true. The underlying database must sort keys based on a key comparator because this method depends on key ordering.

Parameters:

transaction - The transaction we are running in

key - the key to compare keys to

Returns:

true if a Tuple with a key less than or equal to the key argument exists, false otherwise

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying Db

hasGreaterOrEqual

boolean hasGreaterOrEqual(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
                          K key,
                          V val)
                   throws org.apache.directory.api.ldap.model.exception.LdapException

Checks to see if this table has a Tuple with a key equal to the key argument, yet with a value greater than or equal to the value argument provided. The key argument MUST exist for this call to return true and the underlying Db must allow for values of duplicate keys to be sorted. The entire basis to this method depends on the fact that tuples of the same key have values sorted according to a valid value comparator. If the table does not support duplicates then an UnsupportedOperationException is thrown.

Parameters:

transaction - The transaction we are running in

key - the key

val - the value to compare values to

Returns:

true if a Tuple with a key equal to the key argument and a value greater than the value argument exists, false otherwise

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying Db or if the underlying Db is not of the Btree type that allows sorted duplicate values.

hasLessOrEqual

boolean hasLessOrEqual(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
                       K key,
                       V val)
                throws org.apache.directory.api.ldap.model.exception.LdapException

Checks to see if this table has a Tuple with a key equal to the key argument, yet with a value less than or equal to the value argument provided. The key argument MUST exist for this call to return true and the underlying Db must allow for values of duplicate keys to be sorted. The entire basis to this method depends on the fact that tuples of the same key have values sorted according to a valid value comparator. If the table does not support duplicates then an UnsupportedOperationException is thrown.

Parameters:

transaction - The transaction we are running in

key - the key

val - the value to compare values to

Returns:

true if a Tuple with a key equal to the key argument and a value less than the value argument exists, false otherwise

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying Db or if the underlying Db is not of the Btree type that allows sorted duplicate values.

get

V get(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
      K key)
throws org.apache.directory.api.ldap.model.exception.LdapException

Gets the value of a record by key if the key exists. If this Table allows duplicate keys then the first key will be returned. If this Table sorts keys then the key will be the smallest key in the Table as specified by this Table's comparator or the default byte-wise lexical comparator.

Parameters:

transaction - The transaction we are running in

key - the key of the record

Returns:

the value of the record with the specified key if key exists or null if no such key exists.

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying Db

put

void put(org.apache.directory.server.core.api.partition.PartitionTxn writeTransaction,
         K key,
         V value)
  throws org.apache.directory.api.ldap.model.exception.LdapException

Puts a record into this Table. Null is not allowed for keys or values and should result in an IllegalArgumentException.

Parameters:

writeTransaction - The transaction we are running in

key - the key of the record

value - the value of the record.

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read or write to the underlying Db

IllegalArgumentException - if a null key or value is used

remove

void remove(org.apache.directory.server.core.api.partition.PartitionTxn writeTransaction,
            K key)
     throws org.apache.directory.api.ldap.model.exception.LdapException

Removes all records with a specified key from this Table.

Parameters:

writeTransaction - The transaction we are running in

key - the key of the records to remove

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read or write to the underlying Db

remove

void remove(org.apache.directory.server.core.api.partition.PartitionTxn writeTransaction,
            K key,
            V value)
     throws org.apache.directory.api.ldap.model.exception.LdapException

Removes a single key value pair with a specified key and value from this Table.

Parameters:

writeTransaction - The transaction we are running in

key - the key of the record to remove

value - the value of the record to remove

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read or write to the underlying Db

cursor

org.apache.directory.api.ldap.model.cursor.Cursor<org.apache.directory.api.ldap.model.cursor.Tuple<K,V>> cursor()

Creates a Cursor that traverses Tuples in a Table.

Returns:

a Cursor over Tuples containing the key value pairs

cursor

org.apache.directory.api.ldap.model.cursor.Cursor<org.apache.directory.api.ldap.model.cursor.Tuple<K,V>> cursor(org.apache.directory.server.core.api.partition.PartitionTxn partitionTxn,
                                                                                                                K key)
                                                                                                         throws org.apache.directory.api.ldap.model.exception.LdapException

Creates a Cursor that traverses Table Tuples for the same key. Only Tuples with the provided key will be returned if the key exists at all. If the key does not exist an empty Cursor is returned. The motivation behind this method is to minimize the need for callers to actively constrain Cursor operations based on the Tuples they return to a specific key. This Cursor is naturally limited to return only the tuples for the same key.

Parameters:

partitionTxn - The transaction we are running in

key - the duplicate key to return the Tuples of

Returns:

a Cursor over Tuples containing the same key

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there are failures accessing underlying stores

valueCursor

org.apache.directory.api.ldap.model.cursor.Cursor<V> valueCursor(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
                                                                 K key)
                                                          throws org.apache.directory.api.ldap.model.exception.LdapException

Creates a Cursor that traverses Table values for the same key. Only Tuples with the provided key will have their values returned if the key exists at all. If the key does not exist an empty Cursor is returned. The motivation behind this method is to minimize the need for callers to actively constrain Cursor operations to a specific key while removing overheads in creating new Tuples or population one that is reused to return key value pairs. This Cursor is naturally limited to return only the values for the same key.

Parameters:

transaction - The transaction we are running in

key - the duplicate key to return the values of

Returns:

a Cursor over values of a key

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there are failures accessing underlying stores

count

long count(org.apache.directory.server.core.api.partition.PartitionTxn transaction)
    throws org.apache.directory.api.ldap.model.exception.LdapException

Gets the count of the number of Tuples in this Table.

Parameters:

transaction - The transaction we are running in

Returns:

the number of records

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying Db

count

long count(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
           K key)
    throws org.apache.directory.api.ldap.model.exception.LdapException

Gets the count of the number of records in this Table with a specific key: returns the number of duplicates for a key.

Parameters:

transaction - The transaction we are running in

key - the Object key to count.

Returns:

the number of duplicate records for a key.

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying Db

greaterThanCount

long greaterThanCount(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
                      K key)
               throws org.apache.directory.api.ldap.model.exception.LdapException

Gets the number of records greater than or equal to a key value. The specific key argument provided need not exist for this call to return a non-zero value.

Parameters:

transaction - The transaction we are running in

key - the key to use in comparisons

Returns:

the number of keys greater than or equal to the key

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying db

lessThanCount

long lessThanCount(org.apache.directory.server.core.api.partition.PartitionTxn transaction,
                   K key)
            throws org.apache.directory.api.ldap.model.exception.LdapException

Gets the number of records less than or equal to a key value. The specific key argument provided need not exist for this call to return a non-zero value.

Parameters:

transaction - The transaction we are running in

key - the key to use in comparisons

Returns:

the number of keys less than or equal to the key

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - if there is a failure to read the underlying db

close

void close(org.apache.directory.server.core.api.partition.PartitionTxn transaction)
    throws org.apache.directory.api.ldap.model.exception.LdapException

Closes the underlying Db of this Table.

Parameters:

transaction - The transaction we are running in

Throws:

org.apache.directory.api.ldap.model.exception.LdapException - on any failures