org.fastnate.generator

Class EntitySqlGenerator

java.lang.Object

org.fastnate.generator.EntitySqlGenerator

All Implemented Interfaces:

Closeable, AutoCloseable

public class EntitySqlGenerator
extends Object
implements Closeable

Creates SQL statements for a set of entities using their JPA annotations. Known limitations:

• Not all databases covered, see GeneratorDialect.
• Only tested with Hibernate.

Author:

Tobias Liefke

Constructor Summary

Constructors

Constructor and Description
EntitySqlGenerator(Writer writer) Creates a new instance of this EntitySqlGenerator.

Method Summary

Modifier and Type	Method and Description
void	close() Writes any missing SQL and closes the target writer.
protected <E> boolean	findEntity(E entity) Tries to find an entity in an online store.
<E> void	markExistingEntities(Iterable<E> entities) Marks a set of entity references, where we don't know the ID in the database.
<E> void	markExistingEntity(E entity, Number id) Marks an entity reference, where we know the ID in the database.
<E> void	write(E entity) Creates the Import-SQL for an entity.
<E> void	write(Iterable<? extends E> entities) Creates the SQL for the given entities.
void	writeAlignmentStatements() Writes all statements that are necessary to align ID generators in the database with the current IDs.
void	writeComment(String comment) Writes a SQL comment to the associated writer.
protected void	writeStatement(EntityStatement stmt) Writes the given statement to the writer.

Methods inherited from class java.lang.Object

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

Constructor Detail

EntitySqlGenerator

public EntitySqlGenerator(Writer writer)

Creates a new instance of this EntitySqlGenerator.

Parameters:

writer - the writer of the file to generate

Method Detail

close

public void close()
           throws IOException

Writes any missing SQL and closes the target writer.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException - if the target writer throws one

findEntity

protected <E> boolean findEntity(E entity)
                          throws IOException

Tries to find an entity in an online store. Usefull for writing online updates.

Parameters:

entity - the entity to check

Returns:

true if the entity was found and has an id now

Throws:

IOException - if something wents wrong

markExistingEntities

public <E> void markExistingEntities(Iterable<E> entities)
                              throws IOException

Marks a set of entity references, where we don't know the ID in the database. As we write every unknown entity to the SQL file, if it is referenced by one that is just written, we need to mark entities that exist already in the database (and where we possibly have no knowledge of the id of the entity).

Parameters:

entities - the entity to ignore during write(Object)

Throws:

IOException - if the writer throws one

markExistingEntity

public <E> void markExistingEntity(E entity,
                                   Number id)

Marks an entity reference, where we know the ID in the database. As we write every unknown entity to the SQL file, if it is referenced by one that is just written, we need to mark entities that exist already in the database. In difference to markExistingEntities(Iterable), we know the id for the given entity.

Parameters:

entity - the entity to ignore during write(Object)

id - the id of the entity in

write

public <E> void write(E entity)
               throws IOException

Creates the Import-SQL for an entity. If the entity was already written (has an id), it is updated (if nessecary).

Parameters:

entity - the entity to create the SQL for

Throws:

IOException - if the writer throws one

IllegalArgumentException - if the entity is invalid

write

public <E> void write(Iterable<? extends E> entities)
               throws IOException

Creates the SQL for the given entities.

Parameters:

entities - the entities for SQL creation

Throws:

IOException - if the writer throws one

writeAlignmentStatements

public void writeAlignmentStatements()
                              throws IOException

Writes all statements that are necessary to align ID generators in the database with the current IDs.

Throws:

IOException - if the target writer throws one

writeComment

public void writeComment(String comment)
                  throws IOException

Writes a SQL comment to the associated writer.

Parameters:

comment - the comment to write

Throws:

IOException - if thew writer throws one

writeStatement

protected void writeStatement(EntityStatement stmt)
                       throws IOException

Writes the given statement to the writer. May be overridden, if the statements should be written somewhere else (e.g. directly into a database).

Parameters:

stmt - the SQL statement to write

Throws:

IOException - if the writer throws one