de.minee.jpa

Class AbstractStatement<T>

java.lang.Object

de.minee.jpa.AbstractQuery

de.minee.jpa.AbstractStatement<T>

Type Parameters:

T - Class that corresponds to a database table

Direct Known Subclasses:

AbstractJoinClause, SelectStatement

public abstract class AbstractStatement<T>
extends AbstractQuery

Base class for the query builder that contain WHERE restrictions.

Constructor Summary

Constructors

Constructor and Description
AbstractStatement(Class<T> cls, Connection connection) Creates a base for a SELECT statement.

Method Summary

Modifier and Type	Method and Description
<U extends AbstractStatement<T>> void	add(AbstractAndOrConnection<T,U> andOrConnection)
<S> void	add(AbstractJoinClause<S,T> joinClause)
AbstractAndOrConnection<T,AbstractStatement<T>>	and()
protected String	assembleFullSelectQuery() Creates a fully assembled and executable Select Query.
protected String	assembleQuery() Assembles the restriction part of the the query.
T	byId(UUID id) Selects an Object directly by its Id.
protected abstract T	byId(UUID id, Map<Object,Object> handledObjects) Selects an Object directly by its Id or returns a cached Object of the current session.
abstract List<T>	execute()
abstract List<T>	execute(Collection<?> args)
Class<T>	getType() Returns the table class for this statement.
AbstractAndOrConnection<T,AbstractStatement<T>>	or()
AbstractStatement<T>	query(String whereClause) Adds a plain SQL Where string to the Query.
String	toString()

Methods inherited from class de.minee.jpa.AbstractQuery

executeQuery, executeQuery, getConnection

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractStatement

public AbstractStatement(Class<T> cls,
                         Connection connection)

Creates a base for a SELECT statement.

Parameters:

cls - Class that corresponds to a database table

connection - Database connection

Method Detail

add

public <U extends AbstractStatement<T>> void add(AbstractAndOrConnection<T,U> andOrConnection)

add

public <S> void add(AbstractJoinClause<S,T> joinClause)

and

public AbstractAndOrConnection<T,AbstractStatement<T>> and()

or

public AbstractAndOrConnection<T,AbstractStatement<T>> or()

byId

public T byId(UUID id)

Selects an Object directly by its Id.

Parameters:

id - Id of the entry

Returns:

Object with Id id or null if no entry can be found @ SQLException in case of an error

byId

protected abstract T byId(UUID id,
                          Map<Object,Object> handledObjects)

Selects an Object directly by its Id or returns a cached Object of the current session. The cache improves performance, ensures object references and avoids endless cycles.

Parameters:

id - Id of the entry

handledObjects - Object cache of fetched entries in the same session

Returns:

Object with Id id or null if no entry can be found @ SQLException in case of an error

assembleFullSelectQuery

protected String assembleFullSelectQuery()

Creates a fully assembled and executable Select Query.

Returns:

Select Query

assembleQuery

protected String assembleQuery()

Assembles the restriction part of the the query. This can be for example the part of where excluding the 'WHERE' keyword

Returns:

The 'WHERE' part of the statement

getType

public Class<T> getType()

Returns the table class for this statement.

Returns:

Table Class for the Statement, ensured to be not Null

query

public AbstractStatement<T> query(String whereClause)

Adds a plain SQL Where string to the Query. Example:

 select(Foo.class).query("id = 1").execute()
 

Parameters:

whereClause - Plain SQL Where part.

Returns:

this for further processing.

execute

public abstract List<T> execute()

execute

public abstract List<T> execute(Collection<?> args)

toString

public String toString()

Overrides:

toString in class Object