com.banda.serverbase.persistence

Interface GenericDAO<T,PK extends Serializable>

Type Parameters:

T - Type of handled object

PK - The primary key of the object

All Known Implementing Classes:

GenericHibernate3DAO, GenericHibernate4DAO

public interface GenericDAO<T,PK extends Serializable>

Title: GenericDAO

Description: Generic DAO (Data Access Object) containing common methods for object persistence.

Since:

2008

Author:

© Peter Banda

Method Summary

Methods

Modifier and Type	Method and Description
void	clear() Clears session.
void	evict(T object) Evicts given object from session.
boolean	exists(PK id) Checks for existence of an object with given key.
void	flush() Flushes session.
Collection<T>	get(Collection<PK> ids) Generic method to get objects based on class and identifiers.
T	get(PK id) Generic method to get an object based on class and identifier.
List<T>	getAll() Generic method used to get all objects of a particular type.
List<T>	getByExample(T object) Gets objects from the database that match given example.
T	getByUniqueExample(T object) Gets object from the database that match given example.
PK	getKey(T object) Generic method to get the identifier of a given object.
T	getLast() Generic method to get the last object.
PK	getNextPK(PK id) Get primary key larger than given one
PK	getPreviousPK(PK id) Get primary key smaller than given one
void	remove(Collection<T> objects) Generic method to delete a given object
void	remove(PK id) Generic method to delete an object with given id
void	remove(T object) Generic method to delete a given object
<C extends Collection<T>> C	save(C objects) Generic method to save collection of objects - handles insert, update and remove.
T	save(T object) Generic method to save an object - handles insert, update and remove.
void	setKey(T object, PK key) Generic method to set the identifier for a given object.

Method Detail

getAll

List<T> getAll()

Generic method used to get all objects of a particular type.

Returns:

List of populated objects

Throws:

Exception - When database problems occur

get

T get(PK id)

Generic method to get an object based on class and identifier.

Parameters:

id - The identifier (primary key) of the object to get

Returns:

The populated object with given key

Throws:

Exception - When database problems occur

get

Collection<T> get(Collection<PK> ids)

Generic method to get objects based on class and identifiers.

Parameters:

ids - The identifiers (primary keys) of the objects to get

Returns:

The populated objects with given keys

Throws:

Exception - When database problems occur

getLast

T getLast()

Generic method to get the last object.

Returns:

The object with maximal id

getNextPK

PK getNextPK(PK id)

Get primary key larger than given one

Parameters:

id -

Returns:

The next primary key

getPreviousPK

PK getPreviousPK(PK id)

Get primary key smaller than given one

Parameters:

id -

Returns:

The previous primary key

getByExample

List<T> getByExample(T object)

Gets objects from the database that match given example.

Parameters:

object - The template object to match (not null columns)

Returns:

The loaded objects matching given template from the database

Throws:

Exception - When database problems occur

getByUniqueExample

T getByUniqueExample(T object)

Gets object from the database that match given example. There is maximum single object matching given (unique) criteria.

Parameters:

object - The template object to match (not null columns)

Returns:

The loaded object matching given template from the database (if any)

Throws:

Exception - When database problems occur

exists

boolean exists(PK id)

Checks for existence of an object with given key.

Parameters:

id - The id of the entity

Returns:

The result of the test

Throws:

Exception - When database problems occur

save

T save(T object)

Generic method to save an object - handles insert, update and remove.

Parameters:

object - The object to save

Returns:

The persisted object (if not removed)

Throws:

Exception - When database problems occur

save

<C extends Collection<T>> C save(C objects)

Generic method to save collection of objects - handles insert, update and remove.

Type Parameters:

C - Type of collection

Parameters:

objects - The objects to save

Throws:

Exception - When database problems occur

remove

void remove(T object)

Generic method to delete a given object

Parameters:

object - The object to remove

Throws:

Exception - When database problems occur

remove

void remove(Collection<T> objects)

Generic method to delete a given object

Parameters:

object - The object to remove

Throws:

Exception - When database problems occur

remove

void remove(PK id)

Generic method to delete an object with given id

Parameters:

id - The identifier (primary key) of the object to remove

Throws:

Exception - When database problems occur

flush

void flush()

Flushes session.

clear

void clear()

Clears session.

evict

void evict(T object)

Evicts given object from session.

Parameters:

object -

getKey

PK getKey(T object)

Generic method to get the identifier of a given object.

Parameters:

object - The object to get PK for

Returns:

The identifier (primary key) of a given object

setKey

void setKey(T object,
          PK key)

Generic method to set the identifier for a given object.

Parameters:

object - The object to get PK for

key - The identifier (primary key) of a given object