de.taimos.dao.mongo

Class AbstractMongoDAO<T extends AEntity>

java.lang.Object

de.taimos.dao.mongo.AbstractMongoDAO<T>

Type Parameters:

T - the entity this DAO is used for

All Implemented Interfaces:

ICrudDAO<T>

public abstract class AbstractMongoDAO<T extends AEntity>
extends Object
implements ICrudDAO<T>

Copyright 2015 Hoegernet

abstract class to derive to implement Mongo DAOs. The system property mongodb.name has to be set and it denotes the database used for this DAO.

Author:

Thorsten Hoeger

Field Summary

Fields

Modifier and Type	Field and Description
protected org.jongo.MongoCollection	collection

Constructor Summary

Constructors

Constructor and Description
AbstractMongoDAO()

Method Summary

Modifier and Type	Method and Description
protected void	afterDelete(String id)
protected void	afterSave(T object) override this to do something after the object was saved
protected void	beforeDelete(String id)
protected void	beforeSave(T object) override this to do something before the object was saved
protected <P> List<P>	convertIterable(Iterable<P> as) converts the given Iterable to a List
protected org.jongo.Jongo	createJongo(com.mongodb.DB db) creates the Jongo driver instance.
void	delete(String id) deletes the given object using its id.
void	delete(T object) deletes the given object using its id.
T	findById(String id) find the element with the given id
protected List<T>	findByQuery(String query, Object... params) finds all elements matching the given query
protected T	findFirstByQuery(String query, String sort, Object... params) queries with the given string, sorts the result and returns the first element.
List<T>	findList()
protected List<T>	findSortedByQuery(String query, String sort, Object... params) finds all elements matching the given query and sorts them accordingly
protected <P> List<P>	findSortedByQuery(String query, String sort, String projection, Class<P> as, Object... params) finds all elements matching the given query and sorts them accordingly.
protected <P> List<P>	findSortedByQuery(String query, String sort, String projection, org.jongo.ResultHandler<P> handler, Object... params) finds all elements matching the given query and sorts them accordingly.
protected String	getCollectionName()
protected abstract Class<T>	getEntityClass()
void	init()
protected <R> Iterable<R>	mapReduce(String name, com.mongodb.DBObject query, com.mongodb.DBObject sort, Map<String,Object> scope, MapReduceResultHandler<R> conv) runs a map-reduce-job on the collection.
protected <R> Iterable<R>	mapReduce(String name, MapReduceResultHandler<R> conv) runs a map-reduce-job on the collection.
T	save(T object) saves the goven element

Methods inherited from class java.lang.Object

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

Field Detail

collection

protected org.jongo.MongoCollection collection

Constructor Detail

AbstractMongoDAO

public AbstractMongoDAO()

Method Detail

init

@PostConstruct
public final void init()

getCollectionName

protected String getCollectionName()

Returns:

the name of the mongo collection
defaults to the entity's simple name

getEntityClass

protected abstract Class<T> getEntityClass()

Returns:

the entity class of this DAO

mapReduce

protected final <R> Iterable<R> mapReduce(String name,
                                          MapReduceResultHandler<R> conv)

runs a map-reduce-job on the collection. same as mapReduce(name, null, null, null, conv)

Type Parameters:

R - the type of the result class

Parameters:

name - the name of the map-reduce functions

conv - the converter to convert the result

Returns:

an Iterable with the result entries

mapReduce

protected final <R> Iterable<R> mapReduce(String name,
                                          com.mongodb.DBObject query,
                                          com.mongodb.DBObject sort,
                                          Map<String,Object> scope,
                                          MapReduceResultHandler<R> conv)

runs a map-reduce-job on the collection. The functions are read from the classpath in the folder mongodb. The systems reads them from files called <name>.map.js, <name>.reduce.js and optionally <name>.finalize.js. After this the result is converted using the given MapReduceResultHandler

Type Parameters:

R - the type of the result class

Parameters:

name - the name of the map-reduce functions

query - the query to filter the elements used for the map-reduce

sort - sort query to sort elements before running map-reduce

scope - the global scope for the JavaScript run

conv - the converter to convert the result

Returns:

an Iterable with the result entries

Throws:

RuntimeException - if resources cannot be read

findList

public final List<T> findList()

Specified by:

findList in interface ICrudDAO<T extends AEntity>

Returns:

a list of all elements in this collection

convertIterable

protected final <P> List<P> convertIterable(Iterable<P> as)

converts the given Iterable to a List

Type Parameters:

P - the element type

Parameters:

as - the Iterable

Returns:

the converted List

findByQuery

protected final List<T> findByQuery(String query,
                                    Object... params)

finds all elements matching the given query

Parameters:

query - the query to search for

params - the parameters to replace # symbols

Returns:

the list of elements found

findSortedByQuery

protected final List<T> findSortedByQuery(String query,
                                          String sort,
                                          Object... params)

finds all elements matching the given query and sorts them accordingly

Parameters:

query - the query to search for

sort - the sort query to apply

params - the parameters to replace # symbols

Returns:

the list of elements found

findSortedByQuery

protected final <P> List<P> findSortedByQuery(String query,
                                              String sort,
                                              String projection,
                                              Class<P> as,
                                              Object... params)

finds all elements matching the given query and sorts them accordingly. With this method it is possible to specify a projection to rename or filter fields in the result elements. Instead of returning getEntityClass() objects it returns objects of type as

Type Parameters:

P - the element type

Parameters:

query - the query to search for

sort - the sort query to apply

projection - the projection of fields to use

as - the target to convert result elements to

params - the parameters to replace # symbols

Returns:

the list of elements found

findSortedByQuery

protected final <P> List<P> findSortedByQuery(String query,
                                              String sort,
                                              String projection,
                                              org.jongo.ResultHandler<P> handler,
                                              Object... params)

finds all elements matching the given query and sorts them accordingly. With this method it is possible to specify a projection to rename or filter fields in the result elements. Instead of returning getEntityClass() objects it returns objects converted by the given ResultHandler

Type Parameters:

P - the element type

Parameters:

query - the query to search for

sort - the sort query to apply

projection - the projection of fields to use

handler - the handler to convert result elements with

params - the parameters to replace # symbols

Returns:

the list of elements found

findFirstByQuery

protected final T findFirstByQuery(String query,
                                   String sort,
                                   Object... params)

queries with the given string, sorts the result and returns the first element. null is returned if no element is found.

Parameters:

query - the query string

sort - the sort string

params - the parameters to replace # symbols

Returns:

the first element found or null if none is found

findById

public final T findById(String id)

Description copied from interface: ICrudDAO

find the element with the given id

Specified by:

findById in interface ICrudDAO<T extends AEntity>

Parameters:

id - the id to find

Returns:

the obejct with the given id or null if no element exists with this id

save

public final T save(T object)

Description copied from interface: ICrudDAO

saves the goven element

Specified by:

save in interface ICrudDAO<T extends AEntity>

Parameters:

object - the element to save

Returns:

the saved element

afterSave

protected void afterSave(T object)

override this to do something after the object was saved

Parameters:

object - the saved object

beforeSave

protected void beforeSave(T object)

override this to do something before the object was saved

Parameters:

object - the object to be saved

delete

public final void delete(T object)

Description copied from interface: ICrudDAO

deletes the given object using its id.

Specified by:

delete in interface ICrudDAO<T extends AEntity>

Parameters:

object - the object to delete

delete

public final void delete(String id)

Description copied from interface: ICrudDAO

deletes the given object using its id.

Specified by:

delete in interface ICrudDAO<T extends AEntity>

Parameters:

id - the id of the object to delete

beforeDelete

protected void beforeDelete(String id)

afterDelete

protected void afterDelete(String id)

createJongo

protected org.jongo.Jongo createJongo(com.mongodb.DB db)

creates the Jongo driver instance. Override to manipulate the Jongo driver

Parameters:

db - the database to use with the created Jongo

Returns:

the created Jongo driver