package java5.blob; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.sql.Blob; import java.sql.Connection; import java.sql.Date; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import org.junit.Test; import java3.bean.Customer; import java3.util.JDBCUtils; /* * 使用preparedStatement操作Blob类型的数据 */ public class BlobTest { //向数据表customers中插入Blob类型的字段 @Test public void testInsert() throws Exception{ Connection conn = JDBCUtils.getConnedtion(); String sql=insert into customers(name,email,birth,photo)values(?,?,?,?); PreparedStatement ps = conn.prepareStatement(sql); ps.setObject(1, lion); ps.setObject(2, [email protected]); ps.setObject(3, 1111-2-3); FileInputStream is = new FileInputStream(new File(2.png)); ps.setBlob(4, is); ps.execute(); JDBCUtils.closeResource(conn, ps); } //查询数据表customers中Blob类型的字段 @Test public void testQuery() { InputStream is=null; FileOutputStream fos=null; Connection conn =null; PreparedStatement ps=null; ResultSet rs =null; try { conn = JDBCUtils.getConnedtion(); String sql=select id,name,email,birth,photo from customers where id=?; ps = conn.prepareStatement(sql); ps.setObject(1, 21); rs = ps.executeQuery(); if(rs.next()){ int id=rs.getInt(id); String name = rs.getString(name); String email = rs.getString(email); Date birth = rs.getDate(birth); Customer customer = new Customer(id, name, email, birth); System.out.println(customer); //将blob类型的字段下载下来，以文件的方式保存在本地 Blob photo = rs.getBlob(photo); is = photo.getBinaryStream(); fos = new FileOutputStream(3.png); byte[] buffer=new byte[1024]; int len; while((len=is.read(buffer))!=-1){ fos.write(buffer, 0, len); } } } catch (Exception e) { e.printStackTrace(); } finally{ if(is!=null){ try { is.close(); } catch (IOException e) { e.printStackTrace(); } } if(fos!=null){ try { fos.close(); } catch (IOException e) { e.printStackTrace(); } } JDBCUtils.closeResource(conn, ps, rs); } } }