com.impetus.kundera.client

Interface Client<Q extends javax.persistence.Query>

public interface Client<Q extends javax.persistence.Query>

In Kundera, Clients act as a translator of JPA calls to datastore-specific respective operations call. Clients are constructed via ClientFactory that are configurable in persistence.xml. This makes it possible for user to choose a Client implementation for a particular persistence unit. Client API defines methods that are required to be implemented by various clients implementations (Thrift, Mongo etc). Any new addition of datastore support must implement this API. This is because kundera-core - after initialization, caching etc, calls clients methods to read from/ write into datastores.

Author:

vivek.mishra

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Cleans up client
void	deleteByColumn(String schemaName, String tableName, String columnName, Object columnValue) Delete rows from given table for given column name and corresponding value..
Object	executeScript(String script) Enables executing native script specific to a db client
<E> List<E>	find(Class<E> entityClass, Map<String,String> embeddedColumnMap) Finds entities that match a given set of embedded column values provided in the Map
Object	find(Class entityClass, Object key) Retrieves an entity from datastore
<E> List<E>	findAll(Class<E> entityClass, String[] columnsToSelect, Object... keys) Retrieve columnsToSelect from multiple rows of a column-family.
List<Object>	findByRelation(String colName, Object colValue, Class entityClazz) Find list of entities for given column name and column value, if index support is provided..
Object[]	findIdsByColumn(String schemaName, String tableName, String pKeyName, String columnName, Object columnValue, Class entityClazz) Returns array of primary key for given column name and it's value.
<E> List<E>	getColumnsById(String schemaName, String tableName, String pKeyColumnName, String columnName, Object pKeyColumnValue, Class columnJavaType) Returns List of column values for given primary key and column name.
Generator	getIdGenerator() Gets the id generator.
IndexManager	getIndexManager() Gets the index manager.
String	getPersistenceUnit() Gets the persistence unit.
Class<Q>	getQueryImplementor() Returns query implementor class, required for initializing client specific query interface.
EntityReader	getReader() Returns entity reader instance bind to specific client.
void	persist(Node node) Data node to persist entity with specific client.
void	persistJoinTable(JoinTableData joinTableData)
void	remove(Object entity, Object pKey) Removes an entity from datastore for a given primary key

Method Detail

find

Object find(Class entityClass,
          Object key)

Retrieves an entity from datastore

Parameters:

entityClass - the entity class

key - The key of the row

Returns:

Entity object

findAll

<E> List<E> findAll(Class<E> entityClass,
                  String[] columnsToSelect,
                  Object... keys)

Retrieve columnsToSelect from multiple rows of a column-family.

Type Parameters:

E - the element type

Parameters:

entityClass - the entity class

columnsToSelect - Array of column names that need to be populated into entity

keys - Array of row keys

Returns:

List of entity objects

find

<E> List<E> find(Class<E> entityClass,
               Map<String,String> embeddedColumnMap)

Finds entities that match a given set of embedded column values provided in the Map

Type Parameters:

E - the element type

Parameters:

entityClass - the entity class

embeddedColumnMap - Map of embedded column name and their values that are used as a criteria for finding entities

Returns:

the list of entities

close

void close()

Cleans up client

remove

void remove(Object entity,
          Object pKey)

Removes an entity from datastore for a given primary key

Parameters:

entity - the entity

pKey - Primary key of entity to be deleted

getPersistenceUnit

String getPersistenceUnit()

Gets the persistence unit.

Returns:

the persistence unit

getIndexManager

IndexManager getIndexManager()

Gets the index manager.

Returns:

the index manager

persist

void persist(Node node)

Data node to persist entity with specific client.

Parameters:

node - data node.

persistJoinTable

void persistJoinTable(JoinTableData joinTableData)

getColumnsById

<E> List<E> getColumnsById(String schemaName,
                         String tableName,
                         String pKeyColumnName,
                         String columnName,
                         Object pKeyColumnValue,
                         Class columnJavaType)

Returns List of column values for given primary key and column name.

Type Parameters:

E - Type cast

Parameters:

schemaName - Schema/Keyspace name.

tableName - Table/column family name.

pKeyColumnName - Primary key column name.

columnName - Name of column to be fetched.

pKeyColumnValue - primary key value.

Returns:

list of values fetched for

findIdsByColumn

Object[] findIdsByColumn(String schemaName,
                       String tableName,
                       String pKeyName,
                       String columnName,
                       Object columnValue,
                       Class entityClazz)

Returns array of primary key for given column name and it's value.

Parameters:

schemaName - Schema/Keyspace name.

tableName - table/column family name.

pKeyName - primary key column name.

columnName - column name to be used for search.

columnValue - value for parameterised .

entity - class entity class

Returns:

array containing fetched primary keys.

deleteByColumn

void deleteByColumn(String schemaName,
                  String tableName,
                  String columnName,
                  Object columnValue)

Delete rows from given table for given column name and corresponding value..

Parameters:

schemaName - Schema Name

tableName - Name of the table

columnName - Name of the column

columnValue - Name of column value

findByRelation

List<Object> findByRelation(String colName,
                          Object colValue,
                          Class entityClazz)

Find list of entities for given column name and column value, if index support is provided..

Parameters:

colName - the column name

colValue - the column value

entityClass - the entity class

Returns:

the list list of entities.

getReader

EntityReader getReader()

Returns entity reader instance bind to specific client.

Returns:

reader entity reader.

getQueryImplementor

Class<Q> getQueryImplementor()

Returns query implementor class, required for initializing client specific query interface.

Returns:

class instance of configured query interface.

executeScript

Object executeScript(String script)

Enables executing native script specific to a db client

Parameters:

script -

Returns:

getIdGenerator

Generator getIdGenerator()

Gets the id generator.

Returns:

the id generator