Hibernate problem

My program select statement can be issued , but will not issue a delete and update statements , nor error , neighborhoods you probably why.
This is my program

package com.zhg.oa.base;
  
  import java.lang.reflect.ParameterizedType;
  
  import java.util.List;
  
  import javax.annotation.Resource;
  
  import org.hibernate.Session;
  import org.hibernate.SessionFactory;
  
  @SuppressWarnings("unchecked")
  public class DaoSupportImpl<T> implements DaoSupport<T> {
  
  	@Resource
  	private SessionFactory sessionFactory;
  
  	Class<T> clazz;
  
  	public DaoSupportImpl() {
  		// 使用反射技术得到T的真实类型
  		ParameterizedType pt = (ParameterizedType) this.getClass()
  				.getGenericSuperclass();// 获取当前new的对象的泛型的父类类型
  		this.clazz = (Class<T>) pt.getActualTypeArguments()[0];
  	}
  
  	protected Session getSession() {
  		return sessionFactory.getCurrentSession();
  	}
  
  	@Override
  	public void save(T entity) {
  		getSession().save(entity);
  	}
  
  	@Override
  	public void delete(Long id) {
  		Object obj = getById(id);
  System.out.println(obj);
  		if (obj != null) {
  			getSession().delete(obj);
  System.out.println("====================");
  		}
  
  	}
  
  	@Override
  	public void update(T entity) {
  System.out.println("====================");
  		getSession().update(entity);
  System.out.println("==============================");
  	}
  
  	@Override
  	public T getById(Long id) {
  		if (id == null) {
  			return null;
  		} else {
  			return (T) getSession().get(clazz, id);
  		}
  	}
  
  	@Override
  	public List<T> getByIds(Long[] ids) {
  		return getSession().createQuery( //
  				"FROM " + clazz.getSimpleName() + " WHERE id IN (:ids)") //
  				.setParameter("ids", ids)//
  				.list();
  	}
  
  	@Override
  	public List<T> findAll() {
  		return getSession().createQuery( //
  				"FROM " + clazz.getSimpleName()) //
  				.list();
  	}
  }
  

------ Solution ------------------------------------- -------
can send select, the greatest likelihood is that the relationship and transaction .
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    public void delete(Long id) {
          Object obj = getById(id);
  System.out.println(obj);
          if (obj != null) {
              getSession().delete(obj);
  System.out.println("====================");
          }
      }
      @Override
      public void update(T entity) {
  System.out.println("====================");
          getSession().update(entity);
  System.out.println("==============================");
      }

these two codes , " ============ " All energy output, but the delete and update statements directly ignored, there is no data in the database changes
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Well, yes forgot to add affairs , and preceded by the @ Transactional just fine , thank you
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