1 package cn.itcast.jdbc.lob; 2  3 import java.io.File; 4 import java.io.FileReader; 5 import java.io.FileWriter; 6 import java.io.Reader; 7 import java.io.Writer; 8 import java.sql.Connection; 9 import java.sql.PreparedStatement;10 import java.sql.ResultSet;11 12 import org.junit.Test;13 14 import cn.itcast.util.JdbcUtil;15 //大文本的存取16 /*17 use day15;18 create table t1(19     id int primary key,20     content longtext21 );22  */23 public class ClobDemo {24     @Test25     public void testAdd(){26         Connection conn = null;27         PreparedStatement stmt = null;28         try{29             conn = JdbcUtil.getConnection();30             stmt = conn.prepareStatement("insert into t1 (id,content) values (?,?)");31             stmt.setInt(1, 1);32             //大数据要使用流的形式33             File file = new File("c:/jpm.txt");34             Reader reader = new FileReader(file);35             stmt.setCharacterStream(2, reader, (int)file.length());//不能使用long的参数，因为mysql根本支持不到那么大的数据，就没有实现36             37             int i = stmt.executeUpdate();38             if(i>0)39                 System.out.println("插入成功");40             41         }catch(Exception e){42             e.printStackTrace();43         }finally{44             JdbcUtil.release(null, stmt, conn);45         }46     }47     @Test48     public void testRead(){49         Connection conn = null;50         PreparedStatement stmt = null;51         ResultSet rs = null;52         try{53             conn = JdbcUtil.getConnection();54             stmt = conn.prepareStatement("select * from t1 where id=?");55             stmt.setInt(1, 1);56             //大数据要使用流的形式57             //保存到E盘上58             rs = stmt.executeQuery();59             if(rs.next()){60                 Reader reader = rs.getCharacterStream("content");61                 Writer writer = new FileWriter("E:/jpm.txt");62                 char c[] = new char[1024];63                 int len = -1;64                 while((len=reader.read(c))!=-1){65                     writer.write(c, 0, len);66                 }67                 reader.close();68                 writer.close();69             }70             71         }catch(Exception e){72             e.printStackTrace();73         }finally{74             JdbcUtil.release(null, stmt, conn);75         }76     }77 }