JDBC数据库连接MySQL5.7

- 日理万妓 2022-05-26 01:11 229阅读 0赞

1.首先准备mysql 和eclipse环境，在环境搭建好之后，从eclipse官网下载jdbc的驱动包，下载地址http://dev.mysql.com/downloads/connector/j/

2.从下载的文件中取出mysql-connector-java-5.1.31-bin.jar，放到工程中，并导入路径

方法：右击工程名->Build Path->Configure Build Path,选择Add External JAR… 找到mysql-connector-java-5.1.31-bin.jar所在的位置，然后将驱动包加载到项目中，  
![构建路径][70]  
3.写个例子测试一下

package testmysql;  
    import java.sql.*;  
    public class Test {  
      
        public static void main(String[] args) {  
            String driver = "com.mysql.jdbc.Driver";  
            String URL = "jdbc:mysql://localhost:3306/student";  
            Connection con = null;  
            try  
            {  
                Class.forName(driver);  
            }  
            catch(java.lang.ClassNotFoundException e)  
            {  
                System.out.println("Connect Successfull.");  
                System.out.println("Cant't load Driver");  
            }  
            try     
            {                                                                                 
                con=DriverManager.getConnection(URL,"root","root");  
                System.out.println("Connect Successfull.");  
            }   
            catch(Exception e)  
            {  
                System.out.println("Connect fail:" + e.getMessage());  
            }  
        }  
    }

连接上数据库之后，可以根据表中的内容进行数据库表的查询，首先表中要有内容，将一些信息输入到表中之后即可使用SQL语言进行查询

import java.sql.*;    
    public class Main {    
        
        public static void main(String[] args) {    
            String driver = "com.mysql.jdbc.Driver";    
            String URL = "jdbc:mysql://localhost:3306/xiaolu";    
            Connection con = null;  
            ResultSet rs = null;  
            Statement st = null;  
            String sql = "select * from student";  
            try    
            {    
                Class.forName(driver);    
            }    
            catch(java.lang.ClassNotFoundException e)    
            {    
               // System.out.println("Connect Successfull.");    
                System.out.println("Cant't load Driver");    
            }    
            try       
            {                                                                                   
                con=DriverManager.getConnection(URL,"root","root");    
                st=con.createStatement();  
                rs=st.executeQuery(sql);  
                if(rs!=null) {  
                    ResultSetMetaData rsmd = rs.getMetaData();  
                    int countcols = rsmd.getColumnCount();  
                    for(int i=1;i<=countcols;i++) {  
                        if(i>1) System.out.print(";");  
                        System.out.print(rsmd.getColumnName(i)+" ");  
                    }  
                    System.out.println("");  
                    while(rs.next()) {  
                        System.out.print(rs.getString("sno")+"  ");  
                        System.out.print(rs.getString("sname")+"  ");  
                        System.out.print(rs.getString("ssex")+"  ");  
                        System.out.print(rs.getString("sage")+"  ");  
                        System.out.println(rs.getString("sdept")+"  ");  
                    }  
                }  
                //System.out.println("Connect Successfull.");    
                System.out.println("ok");  
                rs.close();  
                st.close();  
                con.close();  
            }     
            catch(Exception e)    
            {    
                System.out.println("Connect fail:" + e.getMessage());    
            }    
        }    
    }

另一份测试代码

package com.lsjckj.jdbc;
    
    import java.sql.Connection; 
    import java.sql.DriverManager; 
    import java.sql.PreparedStatement; 
    import java.sql.ResultSet;
    import java.sql.ResultSetMetaData;
    import java.sql.SQLException;
    import java.sql.Statement;
    import java.util.Properties;
    
    import com.mysql.jdbc.Driver; 
       
    /**
     * @author swayer 2014下午1:20:16
     * 
     */ 
       
    public class JdbcUtil { 
        public static void main(String[] args) throws Exception {
        	//1.创建Driver实现类的对象
            Driver driver = new com.mysql.jdbc.Driver();
            System.out.println(driver);
            //2.创建连接数据库的内容(用户名、密码)对象
            Properties properties = new Properties();
            //3.设置数据库地址
            String url = "jdbc:mysql://127.0.0.1:3306/bdcms";
            //4.通过驱动获取数据库连接对象
            Connection coon =DriverManager.getConnection(url,"root","root");
            System.out.println("Connect Successfull.");
            try {
            	Statement stmt = coon.createStatement();
                String sql="select * from bd_flink";
         		ResultSet rs = stmt.executeQuery(sql);
    
                if(rs!=null) {
                    ResultSetMetaData rsmd = rs.getMetaData();
                    int countcols = rsmd.getColumnCount();
                    for(int i=1;i<=countcols;i++) {
                        if(i>1) System.out.print(";");
                        System.out.print(rsmd.getColumnName(i)+" ");
                    }
                    System.out.println("");
                    while(rs.next()) {
                        System.out.print(rs.getString("flink_id")+"  ");
                        System.out.print(rs.getString("webname")+"  ");
                        System.out.print(rs.getString("logo")+"  ");
                    }
                }
                
                System.out.println("ok");
                rs.close();
                stmt.close();
                coon.close();
            }
            catch(Exception e) {
            	System.out.println("Connect fail:" + e.getMessage());
            }
    	}
    }

[70]: /images/20220526/60c68462856848b88989ddbdf44cfb4e.png