Hibernate读写Oracle BLOB

 

CREATE TABLE TUSER
(
  ID       VARCHAR2(32 BYTE)                    NOT NULL,
  NAME     VARCHAR2(20 BYTE)                    NOT NULL,
  SEX      VARCHAR2(1 BYTE),
  AGE      NUMBER(3),
  ADDRESS  VARCHAR2(100 BYTE),
  PHONE    NUMBER(10),
  EMAIL    VARCHAR2(255 BYTE),
  IMAGE    BLOB,
  RESUME   CLOB
)

public class test2 {
 public static void main(String[] args) {
  // testWriteLob();
  testReadLob();
 }

 public static void testReadLob() {
  Configuration config = new Configuration().configure();
  SessionFactory sessionFactory = config.buildSessionFactory();
  Session session = sessionFactory.openSession();

  String hql = "from ynn.hibernate.model.TUser";
  Query query = session.createQuery(hql);
  List<TUser> list = query.list();
  Iterator<TUser> iter = list.iterator();
  while (iter.hasNext()) {
   TUser user = (TUser) iter.next();
   try {
    InputStream is = user.getImage().getBinaryStream();
    OutputStream os = new FileOutputStream("a.jpg");
//    通过is.availabel()得不到总长度
    byte[] buf = new byte[1024];
    int i = 0;
    while((i=is.read(buf))!=-1){
     os.write(buf,0,i);
    }
    // 以下读Clob
    is = user.getResume().getAsciiStream();
    while((i=is.read(buf))!=-1){
     System.out.println(new String(buf,0,i));
    }
    is.close();
    os.close();
   } catch (SQLException e) {
    e.printStackTrace();
   } catch (FileNotFoundException e) {
    e.printStackTrace();
   } catch (IOException e) {
    e.printStackTrace();
   }
  }
  session.close();
 }

 // Clob ,Blob在SQLSERVER下的读写操作 P138
 // Oracle的Clob, Blob都有自己的游标
 public static void testWriteLob() {
  Configuration config = new Configuration().configure();
  SessionFactory sessionFactory = config.buildSessionFactory();
  Session session = sessionFactory.openSession();

  TUser user = new TUser();
  user.setAge(new Long(20));
  user.setName("Shark");
  user.setImage(Hibernate.createBlob(new byte[1]));
  user.setResume(Hibernate.createClob(" "));

  Transaction tx = session.beginTransaction();
  session.save(user);
  // flush() 强制Hibernate立即执行insert sql
  session.flush();
  // 通过refresh(), 强制Hibernate执行select for update
  session.refresh(user, LockMode.UPGRADE);
  System.out.println(user.getImage().getClass());
  /* 向Blob写入实际内容 */
  // 返回的是SerializableBlob类型的对象,这是个实现了Blob接口的对象,但
  // 不能直接转型为BLOB
  SerializableBlob sb = (SerializableBlob) user.getImage();
  // 需要调用它的getWrappedBlob来转型
  BLOB blob = (BLOB) sb.getWrappedBlob();
  try {
   // 将某个问件读入后,写到Blob字段的输出流中
   OutputStream out = blob.getBinaryOutputStream();
   FileInputStream imgis = new FileInputStream("C:\\kb3.jpg");
   byte[] buf = new byte[102400]; // 10k缓存
   int len;
   while ((len = imgis.read(buf)) > 0) {
    out.write(buf, 0, len);
   }
   imgis.close();
   out.close();
  } catch (SQLException e) {
   e.printStackTrace();
  } catch (FileNotFoundException e) {
   e.printStackTrace();
  } catch (IOException e) {
   e.printStackTrace();
  }
  // 向Clob写入实际内容
  SerializableClob sc = (SerializableClob) user.getResume();
  CLOB clob = (CLOB) sc.getWrappedClob();
  java.io.Writer writer;
  try {
   writer = clob.getCharacterOutputStream();
   writer.write("this is my resume");
   writer.close();
  } catch (SQLException e) {
   e.printStackTrace();
  } catch (IOException e) {
   e.printStackTrace();
  }
  // save
  session.save(user);
  tx.commit();
  session.close();
 }