clob字段的添加和修改

java 代码

public Tb_newsPO saveOrUpdateTb_news(Tb_newsPO tb_news) throws Exception {

        Transaction tx = null;

        try {
            Session s = HibernateSessionFactory.currentSession();
            tx = (Transaction) s.beginTransaction();


            if (tb_news.getId() == null) {

                //初始化clob
                oracle.sql.CLOB clob = oracle.sql.CLOB.empty_lob();
                tb_news.setContents(clob);
//              tb_bbs.setContents(Hibernate.createClob(""));

                s.save(tb_news);
                s.flush();

//              此处一定要用lockMode.UPGRADE模式进行锁定刷新
                s.refresh(tb_news, LockMode.UPGRADE);

                 //获取Tb_newsPO实体的ContentsString属性值
                String content = tb_news.getContentsString();

                 //将获取的辅助字段的值通过oracle.sql.CLOB的putString（）方法赋 值给实体内的Contents字段
                clob = (oracle.sql.CLOB) tb_news.getContents();

                clob.putString(1,content);

                s.update(tb_news);

            } else {
//               首先通过锁模式把该实体读出来
                Tb_newsPO tb_newsold = (Tb_newsPO) s.load(Tb_newsPO.class, tb_news.getId(),LockMode.UPGRADE);


//               获取辅助字段的值
                String contentsStringnew = tb_news.getContentsString();
                System.out.println("contentsStringnew=========="+contentsStringnew);


//            更新前首先要清空原clob字段的内容
                oracle.sql.CLOB clob_empty = oracle.sql.CLOB.empty_lob();
                tb_newsold.setContents(clob_empty);


//            必须要执行以下两步，否则将抛出“不能对空clob进行读写操作”的异常
                s.flush();
                s.refresh(tb_newsold, LockMode.UPGRADE);

//            将获取的辅助字段的值通过oracle.sql.CLOB的putString（）方法赋 值给实体内的summaryClob字段
                oracle.sql.CLOB clob = (oracle.sql.CLOB) tb_newsold.getContents();
                clob.putString(1, contentsStringnew);

                s.update(tb_newsold);
            }
            s.flush();
            tx.commit();
        } catch (Exception e) {
            tx.rollback();
//          e.printStackTrace();
            throw new HibernateException(
                    "Tb_newsDaoHibernate saveOrUpdateTb_news error!" + e);
        }
        return tb_news;
    }