HibernateUtils.java 文件源码

/**
 * @param unitName   persistence unit name
 * @param properties nullable properties for overriding
 * @return created TransactionProvider
 */
public static TransactionProvider setupFactory(String unitName, Map<String, String> properties) {
    if (!providers.containsKey(unitName)) {
        synchronized (HibernateUtils.class) {
            if (!providers.containsKey(unitName)) {
                // Setup Factory & Provider
                EntityManagerFactory factory = Persistence.createEntityManagerFactory(unitName, properties);
                TransactionProvider provider = new TransactionProvider(factory);
                // Put to Map
                providers.put(unitName, provider);
                return provider;
            }
        }
    }
    throw new RuntimeException(new IllegalStateException("Factory already initialized."));
}