blobbean.java~156~

采用web2.0技术,采用动态标签,sql语句全部存储在数据库里面.开发速度快.

package com.sztheater.biz.programe;

import java.sql.*;
import javax.sql.*;
import java.io.*;
import oracle.jdbc.driver.OracleResultSet;
import oracle.sql.BLOB;
public class BlobBean
{

   private Connection conn ;
   /**
    *构造方法,创建Connection对象，并且在数据库中添加一个表。
    */

   public void FreeConn()
   {
       try
       {
           if(conn != null)
               conn.close();
       }
       catch(Exception ex)
       {
           ex.printStackTrace();
       }
       conn = null;
   }
   public BlobBean()throws Exception

   {
       String  strDriver = "com.microsoft.jdbc.sqlserver.SQLServerDriver";
       String strUrl = "jdbc:microsoft:sqlserver://127.0.0.1:1433;DatabaseName=SZTheater";
       String strUser = "SZTheater";
       String strPass = "SZTheater";
       Class.forName(strDriver).newInstance();
       DriverManager.setLoginTimeout(15);
       conn = DriverManager.getConnection(strUrl, strUser, strPass);
      // conn.createStatement().execute("create table  blobtable(blobvalue blob)");
    }
    /**
     *写入Blob数据到数据库
     */
        public void addBlob(String fileName)throws Exception
        {
            conn.setAutoCommit(false);
            String strSQL = "insert into blobtable values (?)";
            PreparedStatement pstmt = conn.prepareStatement(strSQL);

            File binaryFile = new File(fileName);
            System.out.println(fileName+"'s length = " + binaryFile.length());
            FileInputStream instream = new FileInputStream(binaryFile);

            FileInputStream inputtextfile=new FileInputStream(fileName);
            int len = inputtextfile.available();
            byte[] bufferArray = new byte[len];
            inputtextfile.read(bufferArray);

            pstmt.setBytes(1,bufferArray);
            pstmt.execute();
            conn.commit();
        }
        /**
         *从数据库读取blob数据，并且保存在文件系统。
         */
     public void readBlob(String fileName)throws Exception
          {
           conn.setAutoCommit(false);
            Statement stmt = conn.createStatement();
            ResultSet rset = stmt.executeQuery("SELECT blobvalue FROM blobtable");
            byte buffer[] = null;
            while (rset.next()) {
                buffer = rset.getBytes("blobvalue");
            }
            FileOutputStream file_out = new FileOutputStream(new File(fileName));
            int temp;
            file_out.write(buffer);//读取数据、写入文件系统
            file_out.close();
            conn.commit();
        }
        public void test()
        {

        }
        public static void main(String args[])
        {
            String str = "我";
            byte by[] = new byte[2];
            by = str.getBytes();
            for(int i  = 0 ;i <by.length ;i ++)
            {

                System.out.println(by[i]);
            }
        }
}