使用场景

更精细化的事务配置以及事务回归策略

关键代码

    @Override
    @Nullable
    public <T> T execute(TransactionCallback<T> action) throws TransactionException {
        Assert.state(this.transactionManager != null, "No PlatformTransactionManager set");
        if (this.transactionManager instanceof CallbackPreferringPlatformTransactionManager) {
            return ((CallbackPreferringPlatformTransactionManager) this.transactionManager).execute(this, action);
        }
        else {
            TransactionStatus status = this.transactionManager.getTransaction(this);
            T result;
            try {
                result = action.doInTransaction(status);
            }
            catch (RuntimeException | Error ex) {
                // Transactional code threw application exception -> rollback
                rollbackOnException(status, ex);
                throw ex;
            }
            catch (Throwable ex) {
                // Transactional code threw unexpected exception -> rollback
                rollbackOnException(status, ex);
                throw new UndeclaredThrowableException(ex, "TransactionCallback threw undeclared checked exception");
            }
            this.transactionManager.commit(status);
            return result;
        }
    }

使用案例

事务设置

public class UserService implements IUserService {
    private final TransactionTemplate transactionTemplate;
    public UserService(PlatformTransactionManager transactionManager) {
        this.transactionTemplate = new TransactionTemplate(transactionManager);
        // 配置事务隔离级别
        this.transactionTemplate.setIsolationLevel(TransactionDefinition.ISOLATION_READ_UNCOMMITTED);
        // 配置超时时间 （单位秒）
        this.transactionTemplate.setTimeout(30); 
    }
}

事务创建

public class UserService implements Service {
    // 当前实例的所有方法 都可以使用
    private final TransactionTemplate transactionTemplate;
    // 通过构造方法注入
    public UserService(PlatformTransactionManager transactionManager) {
        this.transactionTemplate = new TransactionTemplate(transactionManager);
    }
    public Boolean save() {
        return transactionTemplate.execute(new TransactionCallback() {
            public Object doInTransaction(TransactionStatus status) {
                try {
                    // 一些操作
                    updateOperation1();
                    updateOperation2();
                    return Boolean.TRUE;
                } catch (SomeBusinessException ex) {
                    // 可以配置那些异常需要回滚
                    status.setRollbackOnly();
                     return Boolean.FALSE;
                }
            }
        });
    }
}

参考资料

事务相关【Spring官方文档】