Hibernate存儲，讀取大字段類型數據

存儲大字段

Session session = null; Transaction tx = null; try { session = HibernateSessionFactory.getSession(); tx = session.beginTransaction(); TMeeting meet = new TMeeting(); meet.setMeetname("會議主題"); meet.setMeetfile(Hibernate.createBlob(new byte[1]));//Blob類型的用於存放可進行byte讀寫的數據。例如圖片。 meet.setContent(Hibernate.createClob(" "));//用於存放文本 session.save(meet);//將數據緩存到一級緩存 session.flush();//將數據強制同步到數據庫緩存，但並不提交 session.refresh(meet, LockMode.UPGRADE);//將該對象進行for update Blob blob = meet.getMeetfile(); FileInputStream in = new FileInputStream("c:/1.jpg"); OutputStream out = blob.setBinaryStream(0); byte[] b = new byte[10240]; int len; while((len = in.read(b))!=-1) { out.write(b, 0, len); out.flush(); } in.close(); out.close(); Clob clob = meet.getContent(); BufferedReader reader = new BufferedReader(new FileReader("c:/1.txt")); Writer writer = clob.setCharacterStream(0); String str = null; while((str = reader.readLine())!=null) { writer.write(str); } reader.close(); writer.close(); tx.commit(); } catch (Exception e) { e.printStackTrace(); tx.rollback(); } finally { HibernateSessionFactory.closeSession(); }

 

讀取大字段（一般採用屬性的延遲加載策略）

 

Session session = null; session = HibernateSessionFactory.getSession(); TTest test = (TTest) session.get(TTest.class, 7L); System.out.println("========================="); Clob clobContent = test.getClobcontent(); Blob blobContent = test.getBlobcontent(); try { // 讀取Clob數據 String str = clobContent.getSubString(1L, Integer.parseInt(String.valueOf(clobContent.length()))); System.out.println(str); // 讀取Blob數據 InputStream in = blobContent.getBinaryStream(); byte[] b=new byte[1024]; int len=0; OutputStream out=new FileOutputStream("E:/blobTest.jpg"); while((len=in.read(b))!=-1){ out.write(b, 0, len); out.flush(); } in.close(); out.close(); } catch (Exception e) { e.printStackTrace(); }