用Java程序往oracle写入 和读出 图片

--------写入Oracle的图片

 

 

import java.io.File;
import java.io.FileInputStream;
import java.io.OutputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import oracle.sql.BLOB;

public class JdbcDemo {
 public static void main(String[] args) {
  JdbcDemo obj=new JdbcDemo();
  obj.append_pic_to_Oracle();
 }
 private void append_pic_to_Oracle()
 {
  Connection conn=null;
  BLOB blob=null;
  int foodid=84;
  try {

//加载驱动
   Class.forName("oracle.jdbc.driver.OracleDriver");
   String url="jdbc:oracle:thin:@10.18.45.17:1521:orcl";
   conn=DriverManager.getConnection(url,"wangjun","wangjun");
   conn.setAutoCommit(false);  //把默认提交关闭,即开启了JDBC连接事务

//seq_foodinfo 是一个序列
   String sql="insert into foodinfo values(seq_foodinfo.nextval,?,?,?,empty_blob(),?)";
   PreparedStatement pstmt=conn.prepareStatement(sql);
   pstmt.setString(1, "拉面");
   pstmt.setString(2,"原料：青菜、猪肉、海带、骨头口味");
   pstmt.setDouble(3, 4);
   pstmt.setString(4, "好吃");

//没有返回值就用update
   pstmt.executeUpdate();
   pstmt.close();
   strsql="select image from foodinfo where foodid=? for update";  //锁定即将要更新的记录
   pstmt=conn.prepareStatement(strsql);
   pstmt.setInt(1, foodid);
   ResultSet rs= pstmt.executeQuery();
   if(rs.next())
   {

//当前找到blob
    blob= (BLOB)rs.getBlob(1);
   }
   File f=new File("d:/funny/images/500024.jpg");
   FileInputStream fis=null;
   if(f.exists())
   {

    fis=new FileInputStream(f);
   }
   strsql="update foodinfo set image=? where foodid=?";
   pstmt=conn.prepareStatement(strsql);
   OutputStream os=blob.getBinaryOutputStream();

//为图片开辟一条缓存空间
   byte[] buffer=new byte[(int)f.length()];
   fis.read(buffer);
   os.write(buffer);
   fis.close();
   os.close();
   pstmt.setBlob(1, blob);
   pstmt.setInt(2, foodid);
   pstmt.executeUpdate();
   conn.commit();
  } catch (Exception e) {
   try {
    conn.rollback();
   } catch (SQLException e1) {
    e1.printStackTrace();
   }
   e.printStackTrace();
  }
  finally
  {
   try {

//连接不等于空或者没有关闭的时候
    if(conn!=null || !conn.isClosed())
    {
     conn.close();
    }
   } catch (SQLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }
 }
 
}

 

 

 

 

 

------------------------------------------------------------------------------

----------------在网页中输入图片

 

 

 

先建一个数据库的公用类  DBSession.java  

 

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class DBSession {
 private static final String DRIVER="oracle.jdbc.driver.OracleDriver";
 private static final String URL="jdbc:oracle:thin:@10.18.45.17:1521:orcl";
 private static final String USERNAME="wangjun";
 private static final String PWD="wangjun";
 public static Connection getConnection(){
  Connection conn=null;
  try {
   Class.forName(DRIVER);
   conn=DriverManager.getConnection(URL,USERNAME,PWD);
  } catch (ClassNotFoundException e) {
   e.printStackTrace();
  } catch (SQLException e) {
   e.printStackTrace();
  }
  return conn;
 }
 public static void closeConn(Connection conn)
 {
  try {
   if(conn!=null || !conn.isClosed())
   {
    conn.close();
   }
  } catch (SQLException e) {
   e.printStackTrace();
  }
 }
}

 

 

 

在写一个取出图片的servlet 类

 

 

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Blob;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.webapp.comm.DBSession;

public class GetPicture extends HttpServlet{

 protected void doGet(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  String foodid =request.getParameter("foodid");
  response.setContentType("image/jpg");
  Connection conn=DBSession.getConnection();
  String strsql="select image from foodinfo where foodid=?";
  try {
   PreparedStatement  pstmt=conn.prepareStatement(strsql);
   pstmt.setInt(1,Integer.parseInt(foodid));
   ResultSet rs=pstmt.executeQuery();
   if(rs.next())
   {
    Blob blob= rs.getBlob(1);
    InputStream is= blob.getBinaryStream();
    OutputStream os= response.getOutputStream();
    byte[] buffer=new byte[1024*4];
    int sss=0;
    while((sss=is.read(buffer))!=-1)
    {
     os.write(buffer,0,sss);
    }
    is.close();
    os.flush();
    os.close();
   }
  } catch (SQLException e) {
   e.printStackTrace();
  }
  finally
  {
   DBSession.closeConn(conn);
  }
 }
 protected void doPost(HttpServletRequest req, HttpServletResponse resp)
   throws ServletException, IOException {
 }
  
}

 

 

 

在写一个jsp代码 能去取出代码 

<html>
  <head>
    <title></title>
  </head>
  <body>
    <img  src="getPic?foodid=${param.foodid}" >
  </body>
</html>