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

Field Summary

Fields

Modifier and Type	Field and Description
private GeneratorContext	context Used to keep the state of indices and to store any configuration.
private StatementsWriter	writer The target of any generated SQL statement, e.g. a file or database.

Constructor Summary

Constructors

Constructor and Description
EntitySqlGenerator(GeneratorContext context, Connection connection) Creates a new instance for a database connection.
EntitySqlGenerator(GeneratorContext context, StatementsWriter writer)
EntitySqlGenerator(GeneratorContext context, Writer writer) Creates a new instance for a output writer.

Method Summary

Modifier and Type	Method and Description
void	close() Writes any missing SQL and closes any open resources.
protected <E> boolean	findEntity(E entity) Tries to find an entity in an online store.
void	flush() Writes any open and alignment statements.
GeneratorContext	getContext() Used to keep the state of indices and to store any configuration.
StatementsWriter	getWriter() The target of any generated SQL statement, e.g. a file or database.
private static <E> boolean	isPostponedInsert(List<Object> postInsertEntities, E entity)
<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.
private <E> void	write(E entity, List<Object> postponedEntities) 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 target writer.
private <E> void	writeInserts(E entity, List<Object> postponedEntities, EntityClass<E> classDescription, ColumnExpression discriminator)
void	writePlainStatement(String statement) Writes a plain SQL statement to the target writer.
void	writeSectionSeparator() Writes a new line to the target to separate different sections in the SQL file.
private <E,T> void	writeTableEntities(E entity, List<Object> postponedEntities, Collection<Property<? super E,?>> properties)

Methods inherited from class java.lang.Object

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

Field Detail

context

private final GeneratorContext context

Used to keep the state of indices and to store any configuration.

writer

private final StatementsWriter writer

The target of any generated SQL statement, e.g. a file or database.

Constructor Detail

EntitySqlGenerator

public EntitySqlGenerator(GeneratorContext context,
                          Connection connection)
                   throws SQLException

Creates a new instance for a database connection.

Parameters:

context - the current context that stores any indices and configuration

connection - the database connection

Throws:

SQLException - if the database is not accessible

EntitySqlGenerator

public EntitySqlGenerator(GeneratorContext context,
                          Writer writer)

Creates a new instance for a output writer.

Parameters:

context - the current context that stores any indices and configuration

writer - the stream for the generated file

EntitySqlGenerator

@ConstructorProperties(value={"context","writer"})
 @Generated(value="lombok")
public EntitySqlGenerator(GeneratorContext context,
                                                                                                           StatementsWriter writer)

Method Detail

isPostponedInsert

private static <E> boolean isPostponedInsert(List<Object> postInsertEntities,
                                             E entity)

close

public void close()
           throws IOException

Writes any missing SQL and closes any open resources.

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

flush

public void flush()
           throws IOException

Writes any open and alignment statements.

Throws:

IOException - if the writer throws one

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

private <E> void write(E entity,
                       List<Object> postponedEntities)
                throws IOException

Creates the Import-SQL for an entity. If the entity was already written, nothing happens.

Parameters:

entity - the entity to create the SQL for

postponedEntities - contains entities that will be written later and can be ignored

Throws:

IOException - if the writer throws one

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 target writer. Shortcut for getWriter().writeComment(comment).

Parameters:

comment - the comment to write

Throws:

IOException - if the writer throws one

writeInserts

private <E> void writeInserts(E entity,
                              List<Object> postponedEntities,
                              EntityClass<E> classDescription,
                              ColumnExpression discriminator)
                       throws IOException

Throws:

IOException

writePlainStatement

public void writePlainStatement(String statement)
                         throws IOException

Writes a plain SQL statement to the target writer. Shortcut for getWriter().writePlainStatement(getContext().getDialect(), statement).

Parameters:

statement - the statement to write

Throws:

IOException - if the writer throws one

writeSectionSeparator

public void writeSectionSeparator()
                           throws IOException

Writes a new line to the target to separate different sections in the SQL file. Shortcut for getWriter().writeSectionSeparator().

Throws:

IOException - if the writer throws such an exception

writeTableEntities

private <E,T> void writeTableEntities(E entity,
                                      List<Object> postponedEntities,
                                      Collection<Property<? super E,?>> properties)
                               throws IOException

Throws:

IOException

getContext

@Generated(value="lombok")
public GeneratorContext getContext()

Used to keep the state of indices and to store any configuration.

getWriter

@Generated(value="lombok")
public StatementsWriter getWriter()

The target of any generated SQL statement, e.g. a file or database.