• 纯java方式连接数据库简单操作


    //JDBC全称java datebese connection --java数据库连接

    package com.beiwo;
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.sql.Statement;
    import java.util.ResourceBundle;
    
    /*数据库帮助类*/
    public class DBUtils {
       private static String driverClass;
       private static String url;
       private static String user;
       private static String password;
    	
    	static{
    		ResourceBundle rb=ResourceBundle.getBundle("jdbc");
    		driverClass=rb.getString("driverClass");
    		url=rb.getString("url");
    		user=rb.getString("user");
    		password=rb.getString("password");
    		try {
    			//加载驱动
    			Class.forName(driverClass);
    		} catch (Exception e) {
    		   e.printStackTrace();
    		}
    	}
    	
    	public static Connection getConn() throws SQLException{
    		
    		return DriverManager.getConnection(url, user, password);
    	}
    	public static void closeAll(ResultSet rs,Statement stme,Connection conn){
    		if (null!=rs) {
    			try {
    				rs.close();
    			} catch (SQLException e) {
    				// TODO Auto-generated catch block
    				e.printStackTrace();
    			}
    		}
    		if (null!=rs) {
    			try {
    				stme.close();
    			} catch (SQLException e) {
    				// TODO Auto-generated catch block
    				e.printStackTrace();
    			}
    		}
    		if (null!=rs) {
    			try {
    				conn.close();
    			} catch (SQLException e) {
    				// TODO Auto-generated catch block
    				e.printStackTrace();
    			}
    		}
    package com.beiwo;
    
    import java.sql.Connection;
    
    import java.sql.ResultSet;
    
    import java.sql.Statement;
    
    public class MasterCurd {
    
    	
    public static void findAll(){
    		
    		Connection conn=null;
    	      Statement stme=null;
    	      ResultSet rs=null;
    	      String sql="SELECT * FROM master";
    		  //加载驱动
    		try {
    			//Class.forName("com.mysql.jdbc.Driver");
    			System.out.println("加载成功");
    			conn=DBUtils.getConn();
    			stme= conn.createStatement();
    			rs= stme.executeQuery(sql);
    			while (rs.next()) {
    				System.out.println(rs.getObject(1));
    				System.out.println(rs.getObject(2));
    				System.out.println(rs.getObject(3));
    				System.out.println(rs.getObject(4));
    				System.out.println("=============================");
    			}
    		} catch (Exception e) {
    			
    		}finally{
    			
    			DBUtils.closeAll(rs, stme, conn);
    		}
    		
    	}
    //插入
    public static void Insert (){
    	
        Connection conn=null;
        Statement stme=null;
    	  String sql="INSERT INTO master (name, password, money) VALUES ('张政','123', 100)";
    	 
    	 
    	 try {
    		//获得连接对象
    		conn= DBUtils.getConn();
    		System.out.println("连接成功");
    		 //获取Statement对象
    		stme=conn.createStatement();
    		//执行语句
    		stme.execute(sql);
    		
    	} catch (Exception e) {
    		e.printStackTrace();
    	}finally{
    		
    		DBUtils.closeAll(null, stme, conn);
    	}
    		
    }
    //更新
    public static void Update(){
    	
        Connection conn=null;
        Statement stme=null;
        String sql="UPDATE master SET name='张军',money=50 WHERE id=6";
    	 
    	 
    	 try {
    		//获得连接对象
    		conn= DBUtils.getConn();
    		System.out.println("连接成功");
    		 //获取Statement对象
    		stme=conn.createStatement();
    		//执行语句
    		stme.executeUpdate(sql);
    		
    	} catch (Exception e) {
    		e.printStackTrace();
    	}finally{
    		
    		DBUtils.closeAll(null, stme, conn);
    	}
    		
    }
    //删除
    public static void Delete(){
        Connection conn=null;
        Statement stme=null;
        String sql="DELETE FROM master WHERE id=7";
    	 
    	 
    	 try {
    		//获得连接对象
    		conn= DBUtils.getConn();
    		System.out.println("连接成功");
    		 //获取Statement对象
    		stme=conn.createStatement();
    		//执行语句
    		stme.executeUpdate(sql);
    		
    	} catch (Exception e) {
    		e.printStackTrace();
    	}finally{
    		
    		DBUtils.closeAll(null, stme, conn);
    	}
    		
    }
    	
    }
    
    package com.beiwo;
    
    /*import org.junit.Before;*/
    import org.junit.Test;
    
    public class TestMasterCrud {
    /*	MasterCurd curd=null;
    	@Before
            在前面运行
    	public void befor(){   
    		curd=new MasterCurd();
    		
    	}*/
    	@Test
       public void testFindAll(){
    		MasterCurd.findAll();
    	}
    	@Test
    	   public void Insert(){
    			MasterCurd.Insert();
    		}
    	@Test
    	   public void Update(){
    			MasterCurd.Update();
    		}
    	@Test
    	   public void Delete(){
    			MasterCurd.Delete();
    		}
    }
    
    } }
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  • 原文地址:https://www.cnblogs.com/zzzhangzheng/p/6165756.html
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