林俊海的博客

我們知道可以把二進制數據存進數據庫里去,可是沒做過哦!
前兩天一網友問題怎么做?才去查一下資料,試驗了一下

//Create.java
import java.sql.*;

public class Create {
 public static void main(String[] args) {
  Connection con;    
  Statement st;  
  try {
   Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");    
   String url = "jdbc:odbc:driver={Microsoft Access Driver (*.mdb)};DBQ=C:\\Test\\data.mdb";    
   con = DriverManager.getConnection(url, "", "");    
   st = con.createStatement();

   st.execute("CREATE TABLE mytable(id autoincrement, picname varchar(50), pic image);");
   //我用 Access 做下簡單測試, Oracle 數據庫用 "CREATE TABLE mytable(id autoincrement, picname varchar(50), pic BLOB);" 建表
   st.close();
   con.close();
  } catch(Exception e) {
   e.printStackTrace();
  }
 }
}

// SavePic.java  將圖片保存至數據庫
import java.sql.*;
import java.io.*;

public class SavePic {
 public static void main(String[] args) {
  Connection con;    
  PreparedStatement st; 
  
  try {
   Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");    
   String url = "jdbc:odbc:driver={Microsoft Access Driver (*.mdb)};DBQ=C:\\Test\\data.mdb";    
   con = DriverManager.getConnection(url, "", "");   
   String sql = "INSERT INTO mytable(picname, pic) values('雅林',?)";
   st = con.prepareStatement(sql);
   File f = new File("C:/Test/a.jpg");
   FileInputStream fis = new FileInputStream(f);
   st.setBinaryStream(1, fis, (int)f.length());
   st.executeUpdate();
   st.close();
   con.close();
  } catch(Exception e) {
   e.printStackTrace();
  }
 }
}

//ReadPic.java   從數據庫中讀出圖片存成文件
import java.sql.*;
import java.io.*;

public class ReadPic {

 public static void main(String[] args) {
  Connection con;    
  Statement st; 
  
  try {
   Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");    
   String url = "jdbc:odbc:driver={Microsoft Access Driver (*.mdb)};DBQ=C:\\Test\\data.mdb";    
   con = DriverManager.getConnection(url, "", "");   
   String sql = "SELECT pic FROM mytable WHERE picname='雅林'";
   st = con.createStatement();
   ResultSet rs = st.executeQuery(sql);
   rs.next();
   File f = new File("C:/Test/b.jpg");
   FileOutputStream fos = new FileOutputStream(f);
   InputStream is = rs.getBinaryStream("pic");
   int c;
   byte b[] = new byte[4*1024];
   while ((c=is.read(b))!=-1) {
    fos.write(b, 0, c);
   }
   fos.flush();
   is.close();
   st.close();
   con.close();
  } catch(Exception e) {
   e.printStackTrace();
  }

 }

}