clob读取

转自javaeye某位大侠
import java.io.FileInputStream;   
import java.io.FileOutputStream;   
import java.io.InputStream;   
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 java.sql.Statement;   
  
public class OracleBlobTest {   
    public static void main(String[] args) {   
     new OracleBlobTest().readBlob();
    }   
    public void readBlob() {   
        try {   
         Class.forName("oracle.jdbc.driver.OracleDriver");   
           Connection conn = DriverManager.getConnection(   
                    "jdbc:oracle:thin:@127.0.0.1:1521/july", "scott",   
                    "snaillocke"); 
            PreparedStatement ps = conn.prepareStatement(" SELECT * FROM BLOBTEST WHERE ID=?");   
            ps.setString(1, "1");   
            ResultSet rs = ps.executeQuery();   
            rs.next();   
            oracle.sql.BLOB imgBlob = (oracle.sql.BLOB) rs.getBlob("define");   
  
            // 将二进制数据写入D:/a1.jpg
            try{   
           FileOutputStream outStream = new FileOutputStream("D:/a1.jpg");   
            InputStream inStream = imgBlob.getBinaryStream();   
            byte[] buf = new byte[10240];   
            int len;   
               while ((len = inStream.read(buf)) > 0) {   
                    outStream.write(buf, 0, len);   
               }   
                inStream.close();   
                outStream.close();   
            }catch(Exception e) {   
                e.printStackTrace();   
            }   
               
 
        } catch (ClassNotFoundException e) {   
            e.printStackTrace();   
        } catch (SQLException e) {   
            e.printStackTrace();   
        }   
    }   
   public static void writeBlob() {   
        try {   
            Class.forName("oracle.jdbc.driver.OracleDriver");   
           Connection conn = DriverManager.getConnection(   
                    "jdbc:oracle:thin:@127.0.0.1:1521/july", "scott",   
                    "snaillocke");   
            Statement st = conn.createStatement();   
            // 插入一个空对象empty_blob()
           // 锁定数据行进行更新，注意“for update”语句
            PreparedStatement ps = conn.prepareStatement("insert into BLOBTEST (ID, NAME, PICTURE) values (1,'fang.jpg',?)");   
            // 通过ORALCE.SQL.BLOB/CLOB.EMPTY_LOB()构造空BLOB/CLOB对象
           ps.setBlob(1, oracle.sql.BLOB.empty_lob());   
            ps.execute();   
            ps.close();   
  
            // 再次对读出BLOB/CLOB句柄
           ps = conn   
                    .prepareStatement("SELECT * FROM BLOBTEST WHERE ID=? FOR UPDATE");   
            ps.setInt(1, 1);   
  
            ResultSet rs = ps.executeQuery();   
            rs.next();   
  
            oracle.sql.BLOB imgBlob = (oracle.sql.BLOB) rs.getBlob(3);   
  
            // 将二进制数据写入BLOB
            try{   
            FileInputStream inStream = new FileInputStream("D:/My Pictures/oracle.png");   
            OutputStream outStream = imgBlob.getBinaryOutputStream();   
            byte[] buf = new byte[10240];   
            int len;   
                while ((len = inStream.read(buf)) > 0) {   
                    outStream.write(buf, 0, len);   
                }   
                inStream.close();   
                outStream.close();   
            }catch(Exception e) {   
                e.printStackTrace();   
            }   
  
            // 再将Blob字段更新到数据库
            ps = conn   
                    .prepareStatement(" update BLOBTEST set PICTURE=?");   
            ps.setBlob(1, imgBlob);   
            ps.executeUpdate();   
  
       } catch (ClassNotFoundException e) {   
            e.printStackTrace();   
       } catch (SQLException e) {   
            e.printStackTrace();   
       }   
   }   
}
注意oracle的驱动要有,肯定好用,不明白的给我留言