使用jdbc存储图片和大文本

package cn.itcast.i_batch;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.Statement;
import java.util.Arrays;

import org.junit.Test;

import cn.itcast.e_tool.JDBCUtils;
public class Demo {
    @Test
    //1 使用Statement对象批量执行sql
    public void fun1() throws Exception{
        
        //1 获得连接
        Connection conn = JDBCUtils.getConnection();
        //2 获得Statement
    Statement st =    conn.createStatement();
        //3 添加多条sql语句到st中
    
    st.addBatch("create table t_stu ( id int primary key auto_increment , name varchar(20) )");
    st.addBatch("insert into t_stu values(null,'tom')");
    st.addBatch("insert into t_stu values(null,'jerry')");
    st.addBatch("insert into t_stu values(null,'jack')");
    st.addBatch("insert into t_stu values(null,'rose')");
        //4 执行sql
    int[]  results = st.executeBatch();
    System.out.println(Arrays.toString(results));
        //5关闭资源
        JDBCUtils.close(conn, st, null);
        }
    @Test
    //2 使用PrepareStatement对象批量执行sql
    public void fun2() throws Exception{
        
        //1 获得连接
        Connection conn = JDBCUtils.getConnection();
        //2 书写sql语句
        String sql = "insert into t_stu values(null,?)";
        //3 创建PrepareStatement
        PreparedStatement ps = conn.prepareStatement(sql);
        //4 循环.添加参数
        for(int i=0;i<100;i++){
            ps.setString(1, "用户"+i);
            ps.addBatch();
        }
        //5 批量执行
        int[]  results =ps.executeBatch();
        System.out.println(Arrays.toString(results));
        //5关闭资源
        JDBCUtils.close(conn, ps, null);
        }
}

 

 1.使用jdbc存储大文本

package cn.itcast.g_text;

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

import org.junit.Test;

import cn.itcast.e_tool.JDBCUtils;
public class Demo {
    @Test
    //演示向mysql中存放大文本数据
    //存储大文本必须使用PrepareStatement对象
    public void fun1() throws Exception{
        
        //1 获得连接
        Connection conn = JDBCUtils.getConnection();
        //2 书写sql
        String sql = "insert into mytext values(null,?)";
        //3 创建PrepareStatement
        PreparedStatement ps = conn.prepareStatement(sql);
        //4 设置参数
        //参数1:参数的索引
        //参数2:需要保存的文本的流
        //参数3:文件长度
        
        File f = new File("src/text.txt");
        
        FileReader reader = new FileReader(f);
        
        ps.setCharacterStream(1, reader, (int)f.length());
        
        //5 执行sql
        int result = ps.executeUpdate();
        System.out.println(result);
        //6关闭资源
        JDBCUtils.close(conn, ps, null);
        }
    
}

 

2.使用jdbc存储图片

ackage cn.itcast.h_blob;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;

import org.junit.Test;

import cn.itcast.e_tool.JDBCUtils;
public class Demo {
    @Test
    //演示向mysql中存放图片
    //存储图片必须使用PrepareStatement对象
    public void fun1() throws Exception{
        
        //1 获得连接
        Connection conn = JDBCUtils.getConnection();
        //2 书写sql
        String sql = "insert into myblob values(null,?)";
        //3 创建PrepareStatement
        PreparedStatement ps = conn.prepareStatement(sql);
        //4 设置参数
        //参数1:参数的索引
        //参数2:需要保存的图片的流
        //参数3:图片文件长度
        
        File f = new File("src/wg.PNG");
        
        InputStream  is = new FileInputStream(f);
        
        ps.setBinaryStream(1, is, (int)f.length());
        
        //5 执行sql
        int result = ps.executeUpdate();
        System.out.println(result);
        //6关闭资源
        JDBCUtils.close(conn, ps, null);
        }
    
}

 

3.批量执行sql