标签:style class blog c code java
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 longtext 21 ); 22 */ 23 public class ClobDemo { 24 @Test 25 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 @Test 48 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 }
标签:style class blog c code java
原文地址:http://www.cnblogs.com/friends-wf/p/3747922.html