java-Eclipse中使用JDBC连接数据库

Posted 2021-01-26 黑魔法os

准备工作：mysql-connector-java-5.1.6-bin.jar配置


package com.job;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class yy {
   // JDBC 驱动器名称 和数据库地址
   static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";  
   //数据库的名称为 EXAMPLE
   static final String DB_URL = "jdbc:mysql://localhost/EXAMPLE";

   //  数据库用户和密码
   static final String USER = "root";

   static final String PASS = "123456";

   public static void main(String[] args) {
       Connection conn = null;
       Statement stmt = null;
       try{
           //注册JDBC 驱动程序
           Class.forName("com.mysql.jdbc.Driver");

           //打开连接
           System.out.println("Connecting to database...");
           conn = DriverManager.getConnection(DB_URL,USER,PASS);

           //执行查询
           System.out.println("Creating statement...");
           stmt = conn.createStatement();
           String sql;
           sql = "SELECT id, name, age FROM Students";
           ResultSet rs = stmt.executeQuery(sql);
 
           //得到和处理结果集
           while(rs.next()){
               //检索
               int id  = rs.getInt("id");
               int age = rs.getInt("age");
               String name = rs.getString("name");

               //显示
               System.out.print("ID: " + id);
               System.out.print(", Age: " + age);
               System.out.print(", Name: " + name);
               System.out.println();
           }
           //清理环境
           rs.close();
           stmt.close();
           conn.close();
       }catch(SQLException se){
           // JDBC 操作错误
           se.printStackTrace();
       }catch(Exception e){
           // Class.forName 错误
           e.printStackTrace();
       }finally{
           //这里一般用来关闭资源的
           try{
               if(stmt!=null)
                   stmt.close();
           }catch(SQLException se2){
           }
           try{
               if(conn!=null)
                   conn.close();
           }catch(SQLException se){
               se.printStackTrace();
           }
       }
       System.out.println("Goodbye!");
   }
}