org.springframework.transaction.annotation.TransactionManagementConfigurer#org.springframework.transaction.TransactionManager源码实例Demo

/**
 * Return the default transaction manager bean to use for annotation-driven database
 * transaction management, i.e. when processing {@code @Transactional} methods.
 * <p>There are two basic approaches to implementing this method:
 * <h3>1. Implement the method and annotate it with {@code @Bean}</h3>
 * In this case, the implementing {@code @Configuration} class implements this method,
 * marks it with {@code @Bean} and configures and returns the transaction manager
 * directly within the method body:
 * <pre class="code">
 * &#064;Bean
 * &#064;Override
 * public PlatformTransactionManager annotationDrivenTransactionManager() {
 *     return new DataSourceTransactionManager(dataSource());
 * }</pre>
 * <h3>2. Implement the method without {@code @Bean} and delegate to another existing
 * {@code @Bean} method</h3>
 * <pre class="code">
 * &#064;Bean
 * public PlatformTransactionManager txManager() {
 *     return new DataSourceTransactionManager(dataSource());
 * }
 *
 * &#064;Override
 * public PlatformTransactionManager annotationDrivenTransactionManager() {
 *     return txManager(); // reference the existing {@code @Bean} method above
 * }</pre>
 * If taking approach #2, be sure that <em>only one</em> of the methods is marked
 * with {@code @Bean}!
 * <p>In either scenario #1 or #2, it is important that the
 * {@code PlatformTransactionManager} instance is managed as a Spring bean within the
 * container as all {@code PlatformTransactionManager} implementations take advantage
 * of Spring lifecycle callbacks such as {@code InitializingBean} and
 * {@code BeanFactoryAware}.
 * @return a {@link org.springframework.transaction.PlatformTransactionManager} or
 * {@link org.springframework.transaction.ReactiveTransactionManager} implementation
 */
TransactionManager annotationDrivenTransactionManager();
 

/**
 * Specify the <em>default</em> transaction manager to use to drive transactions.
 * This can either be a traditional {@link PlatformTransactionManager} or a
 * {@link ReactiveTransactionManager} for reactive transaction management.
 * <p>The default transaction manager will be used if a <em>qualifier</em>
 * has not been declared for a given transaction or if an explicit name for the
 * default transaction manager bean has not been specified.
 * @see #setTransactionManagerBeanName
 */
public void setTransactionManager(@Nullable TransactionManager transactionManager) {
	this.transactionManager = transactionManager;
}
 

/**
 * Return the default transaction manager, or {@code null} if unknown.
 * This can either be a traditional {@link PlatformTransactionManager} or a
 * {@link ReactiveTransactionManager} for reactive transaction management.
 */
@Nullable
public TransactionManager getTransactionManager() {
	return this.transactionManager;
}