Hiberante读取BLOB数据类型.

package cn.com.yyaccp.exam.daoimp; import java.io.IOException; import java.io.InputStream; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.OutputStream; import java.sql.Blob; import java.sql.SQLException; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import oracle.sql.BLOB; import org.hibernate.Hibernate; import org.hibernate.LockMode; import org.hibernate.Query; import org.hibernate.Session; import org.hibernate.lob.SerializableBlob; import cn.com.yyaccp.exam.dao.ReadOrWriter; import cn.com.yyaccp.exam.hiberante.util.HibernateSessionFactory; import cn.com.yyaccp.exam.pojo.Clsinfo; import cn.com.yyaccp.exam.pojo.Student; public class ReadOrWriterOperater implements ReadOrWriter { Session session = null; public Object read(int id) { Object obj = null; session = HibernateSessionFactory.currentSession(true);//获得当前的Session Object blobObj = session.load(Clsinfo.class, new Long(id));//根据传入的ID找到对应的数据信息 if (blobObj != null) { Clsinfo clsblob = (Clsinfo) blobObj; Blob blob = clsblob.getClstu(); InputStream in; try { in = blob.getBinaryStream();//得到输入的二进制流 ObjectInputStream objIn = new ObjectInputStream(in);//用二进制对象流读取对象 obj = objIn.readObject(); objIn.close(); in.close(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } session.beginTransaction().commit(); return obj; } public void write(Object obj) {// 要插入blob字段的对象 Clsinfo clsinfo = new Clsinfo(); clsinfo.setClassname("t17");// clsInfo表中ClassName字段 clsinfo.setClstu(Hibernate.createBlob(new byte[1]));// clsInfo表中的blob字段用于存储student对象(预留一个字节的空间) Session session; Object id = null; try { session = HibernateSessionFactory.currentSession(true);// 获得当前的session id = session.save(clsinfo); session.flush(); session.refresh(clsinfo, LockMode.UPGRADE);// 锁定当前的行进行更新 SerializableBlob sb = (SerializableBlob) clsinfo.getClstu(); // 需要调用它的getWrappedBlob来转型 BLOB blob = (BLOB) sb.getWrappedBlob(); OutputStream out = blob.getBinaryOutputStream(); ObjectOutputStream objOut = new ObjectOutputStream(out); objOut.writeObject(obj); objOut.flush(); objOut.close(); out.close(); HibernateSessionFactory.commitTransaction(); HibernateSessionFactory.closeSession(); System.out.println("写入成功..."); // session. } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void update(int id, Object obj) {//obj为要更新的Blob字段的对象 Session session = null; try { session = HibernateSessionFactory.currentSession(true); Object blobObj = session.load(Clsinfo.class, new Long(id));//根据ID找到对应的记录 // session.flush(); if (blobObj != null) {//如果找到的对象不为空 Clsinfo clsinfo = (Clsinfo) blobObj;//转换为Clsinfo对象 clsinfo.setClstu(Hibernate.createBlob(new byte[1])); session.saveOrUpdate(clsinfo);//更新相关信息 session.flush(); session.refresh(blobObj, LockMode.UPGRADE);//锁定要更新的行 SerializableBlob sb = (SerializableBlob) clsinfo.getClstu();//先换成SerializableBlob然后转换为BloB对象 BLOB blob = (BLOB) sb.getWrappedBlob();//BLOB为oracle.sql.BLOB; OutputStream out = blob.getBinaryOutputStream();//将对象转换成二进制输出流 ObjectOutputStream objOut = new ObjectOutputStream(out); objOut.writeObject(obj);//用对象输出流写入数据中 objOut.flush(); objOut.close(); out.close(); } HibernateSessionFactory.commitTransaction(); HibernateSessionFactory.closeSession(); System.out.println("更新成功..."); } catch (Exception e) { e.printStackTrace(); } } }