jdbc 3.0

1.将Blob、Clob类型数据保存到数据库

 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileReader;
 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.PreparedStatement;

 public class Test4 {
     /**
      * 将图片、文本保存在数据库
      * Blob、Clob
      * @author 容杰龙
      */
     public static void main(String[] args) {
         try {
             Class.forName("com.mysql.jdbc.Driver");
             String url="jdbc:mysql://localhost:3306/rjl";
             String user="rjl";
             String password="123";
             Connection conn = DriverManager.getConnection(url, user, password);
             String sql1="insert into pic(img,msg) values(?,?)";

             File file=new File("C:/Users/Rong/Desktop/qq.png");
             FileInputStream inputStream = new FileInputStream(file);

             FileReader reader = new FileReader("C:/Users/Rong/Desktop/msg.txt");

             PreparedStatement ps = conn.prepareStatement(sql1);
             //字节流-二进制图像
             ps.setBlob(1, inputStream);
             //字符流
             ps.setClob(2, reader);
             int count = ps.executeUpdate();
             if (count>0) {
                 System.out.println("添加成功！");
             }
         } catch (Exception e) {
             e.printStackTrace();
         }

     }

 }

2.从数据库表里读取Blob、Clob类型数据

 package com.rong.web;

 import java.io.FileOutputStream;
 import java.io.FileWriter;
 import java.io.InputStream;
 import java.io.Reader;
 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;

 public class Test5 {

     /**
      * 读取MySQL数据库Blob、Clob类型的数据到硬盘
      * @author 容杰龙
      */
     public static void main(String[] args) {
         try {
             Class.forName("com.mysql.jdbc.Driver");
             String url="jdbc:mysql://localhost:3306/rjl?user=root&password=123123";
             Connection conn = DriverManager.getConnection(url);
             String sql="select * from pic where id=?";
             PreparedStatement ps = conn.prepareStatement(sql);
             ps.setInt(1, 1);
             ResultSet rs = ps.executeQuery();
             while(rs.next()){
                 //获取字节输入流
                 InputStream inputStream = rs.getAsciiStream("img");
                 //获取字符输入流
                 Reader reader = rs.getCharacterStream("msg");
                 byte[] bytes=new byte[1024];
                 char[] chars=new char[1024];
                 int len=0;
                 //创建文件输出流，设置文件存储的硬盘位置
                 FileOutputStream fos = new FileOutputStream("C:/Users/Administrator/Desktop/jdbc.png");
                 FileWriter fw = new FileWriter("C:/Users/Administrator/Desktop/jdbc.txt");
                 //字节输出
                 while ((len=inputStream.read(bytes))!=-1) {
                     fos.write(bytes, 0, len);
                 }
                 fos.close();
                 inputStream.close();
                 len=0;
                 //字符输出
                 while ((len=reader.read(chars))!=-1) {
                     fw.write(chars, 0, len);
                 }
                 fw.close();
                 reader.close();

             }
         } catch (Exception e) {
             e.printStackTrace();
         }

     }

 }

 package com.rong.web;

 import java.io.FileOutputStream;
 import java.io.FileWriter;
 import java.io.InputStream;
 import java.io.Reader;
 import java.sql.Blob;
 import java.sql.Clob;
 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;

 public class Test6 {

     /**
      * 读取MySQL数据库Blob、Clob类型的数据到硬盘
      * @author 容杰龙
      */
     public static void main(String[] args) {
         try {
             Class.forName("com.mysql.jdbc.Driver");
             String url="jdbc:mysql://localhost:3306/rjl?user=root&password=123123";
             Connection conn = DriverManager.getConnection(url);
             String sql="select * from pic where id=?";
             PreparedStatement ps = conn.prepareStatement(sql);
             ps.setInt(1, 1);
             ResultSet rs = ps.executeQuery();
             while(rs.next()){
                 //获取blob对象
                 Blob blob = rs.getBlob("img");
                 //获取二进制字节输入流
                 InputStream binaryStream = blob.getBinaryStream();
                 //////////////////////////////////////////////////

                 //获取clob对象
                 Clob clob = rs.getClob("msg");
                 //获取字符输入流
                 Reader characterStream = clob.getCharacterStream();

                 byte[] bytes=new byte[1024];
                 char[] chars=new char[1024];
                 int len=0;
                 //创建文件输出流，设置文件存储的硬盘位置
                 FileOutputStream fos = new FileOutputStream("C:/Users/Administrator/Desktop/jdbc.png");
                 FileWriter fw = new FileWriter("C:/Users/Administrator/Desktop/jdbc.txt");
                 //字节输出
                 /////////////////////////////////
 //                byte[] bs = rs.getBytes("img");
 //                fos.write(bs);
                 ////////////////////////////////////
                 while ((len=binaryStream.read(bytes))!=-1) {
                     fos.write(bytes, 0, len);
                 }
                 fos.close();
                 binaryStream.close();
                 len=0;
                 //字符输出
                 while ((len=characterStream.read(chars))!=-1) {
                     fw.write(chars, 0, len);
                 }
                 fw.close();
                 characterStream.close();

             }
         } catch (Exception e) {
             e.printStackTrace();
         }

     }

 }