Creating EJB 3.0 Entity Relationships - EJB 3.0 Database Persistence with Oracle Fusion Middleware 11g - page 237

article.setTitle("Test-Driven Design");
em.persist(article);
em.merge(msdn_features);
msdn_features.addArticle(article);
em.flush();
article = new Article(msdn_features);
article.setId(6022009);
article.setTitle("Entity Framework");
em.persist(article);
msdn_features.addArticle(article);
em.flush();
Section columns = new Section();
columns.setId("MSDN_Mag_Columns_062009");
columns.setSectionName("COLUMNS");
em.persist(columns);
em.merge(edition);
edition.addSection(columns);
Add an article to the columns section:
article = new Article(columns);
article.setId(6032009);
article.setTitle("Windows With C++");
em.persist(article);
em.merge(columns);
columns.addArticle(article);
em.flush();
Add another article to the columns section:
article = new Article(columns);
article.setId(6042009);
article.setTitle("Patterns in Practice");
em.persist(article);
columns.addArticle(article);
em.flush();
em.merge(catalog2);
catalog2.addEdition(edition);
edition = new Edition();
edition.setId(52009);
edition.setEdition("May 2009");
em.persist(edition);
msdn_features = new Section();
msdn_features.setId("MSDN_Mag_Features_052009");