org.panteleyev.persistence

Class DAO

java.lang.Object

org.panteleyev.persistence.DAO

public class DAO
extends Object

Persistence API entry point.

Constructor Summary

Constructors

Constructor and Description
DAO()
DAO(DataSource ds)

Method Summary

Modifier and Type	Method and Description
void	createTables(List<Class<? extends Record>> tables) This method creates table for the specified classes according to their annotations.
void	delete(Integer id, Class<? extends Record> clazz) Deletes record from the database.
void	delete(Record record) Deleted record from the database.
Integer	generatePrimaryKey(Class<? extends Record> clazz) Returns next available primary key value.
<T extends Record> T	get(Integer id, Class<? extends T> clazz) Retrieves record from the database using record ID.
<T extends Record> List<T>	getAll(Class<T> clazz) Retrieves all records of the specified type.
<T extends Record> void	getAll(Class<T> clazz, Map<Integer,T> result) Retrieves all records of the specified type and fills the map.
Connection	getConnection() Returns connection for the current data source.
DataSource	getDataSource() Return current data source object.
<T extends Record> void	insert(int size, List<T> records) This method inserts multiple records with predefined id using batch insert.
<T extends Record> T	insert(T record) This method inserts new record with predefined id into the database.
void	preload(Collection<Class<? extends Record>> tables) Pre-loads necessary information from the just opened database.
void	setDataSource(DataSource ds) Sets a new data source.
<T extends Record> T	update(T record) Updates record in the database.

Methods inherited from class java.lang.Object

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

Constructor Detail

DAO

public DAO()

DAO

public DAO(DataSource ds)

Method Detail

getDataSource

public DataSource getDataSource()

Return current data source object.

Returns:

data source object

setDataSource

public void setDataSource(DataSource ds)

Sets a new data source.

Parameters:

ds - data source

getConnection

public Connection getConnection()
                         throws SQLException

Returns connection for the current data source.

Returns:

connection

Throws:

SQLException - in case of SQL error

get

public <T extends Record> T get(Integer id,
                                Class<? extends T> clazz)

Retrieves record from the database using record ID.

Type Parameters:

T - type of the record

Parameters:

id - record id

clazz - record class

Returns:

record

getAll

public <T extends Record> List<T> getAll(Class<T> clazz)

Retrieves all records of the specified type.

Type Parameters:

T - type of the record

Parameters:

clazz - record class

Returns:

list of records

getAll

public <T extends Record> void getAll(Class<T> clazz,
                                      Map<Integer,T> result)

Retrieves all records of the specified type and fills the map.

Type Parameters:

T - type of the record

Parameters:

clazz - record class

result - map to fill

createTables

public void createTables(List<Class<? extends Record>> tables)

This method creates table for the specified classes according to their annotations.

Parameters:

tables - list of tables

preload

public void preload(Collection<Class<? extends Record>> tables)

Pre-loads necessary information from the just opened database. This method must be called prior to any other database operations. Otherwise primary keys may be generated incorrectly.

Parameters:

tables - list of Record types

generatePrimaryKey

public Integer generatePrimaryKey(Class<? extends Record> clazz)

Returns next available primary key value. This method is thread safe.

Parameters:

clazz - record class

Returns:

primary key value

insert

public <T extends Record> T insert(T record)

This method inserts new record with predefined id into the database. No attempt to generate new id is made. Calling code must ensure that predefined id is unique.

Type Parameters:

T - type of the record

Parameters:

record - record

Returns:

inserted record

insert

public <T extends Record> void insert(int size,
                                      List<T> records)

This method inserts multiple records with predefined id using batch insert. No attempt to generate new id is made. Calling code must ensure that predefined id is unique for all records.

Supplied records are divided to batches of the specified size. To avoid memory issues size of the batch must be tuned appropriately.

Type Parameters:

T - type of records

Parameters:

size - size of the batch

records - list of records

update

public <T extends Record> T update(T record)

Updates record in the database. This method returns instance of the Record, i.e. supplied object is not changed.

Type Parameters:

T - record type

Parameters:

record - record

Returns:

updated record

delete

public void delete(Record record)

Deleted record from the database.

Parameters:

record - record to delete

delete

public void delete(Integer id,
                   Class<? extends Record> clazz)

Deletes record from the database.

Parameters:

id - id of the record

clazz - record type