java 连接mysql增删改查

package com.test.dao; 2 3 import com.test.entity.Person; 4 5 import java.sql.DriverManager; 6 import java.sql.PreparedStatement; 7 import java.sql.ResultSet; 8 import java.sql.SQLException; 9 10 /** 11 * Created by wdw on 2017/9/7. 12 */ 13 public class PersonDao { 14 15 private final static String DRIVER = "com.mysql.jdbc.Driver"; 16 private final static String URL = "jdbc:mysql://localhost:3306/wdw"; 17 private final static String USERNAME = "root"; 18 private final static String PASSWORD = "123456"; 19 20 /** 21 * 添加一个人 22 * 23 * @param person 24 * @return boolean 25 */ 26 public boolean insert(Person person) { 27 boolean flag = false;// 28 try { 29 Class.forName(DRIVER);//加载数据库驱动 30 java.sql.Connection conn = DriverManager.getConnection(URL, USERNAME, PASSWORD); 31 // 使用jar包中的connection接口，并通过DriveManager类的静态方法getConnection()创建连接对象conn 32 String sql = "INSERT INTO sys_users(id,name,code) VALUES(?,?,?)";//编写sql语句 33 PreparedStatement ps = conn.prepareStatement(sql);////创建预处理对象ps 34 ps.setInt(1, person.getId()); 35 ps.setString(2, person.getName()); 36 ps.setString(3, person.getCode()); 37 38 if (ps.executeUpdate() > 0) { 39 flag = true; 40 } 41 System.out.print(flag); 42 ps.close(); 43 conn.close(); 44 45 } catch (ClassNotFoundException e) { 46 47 e.printStackTrace(); 48 } catch (SQLException e) { 49 e.printStackTrace(); 50 } 51 return flag; 52 } 53 54 /** 55 * 添加一个人 56 * 57 * @param id 58 * @return boolean 59 */ 60 public Person selectById(String id) { 61 Person p = new Person(); 62 try { 63 Class.forName(DRIVER);//加载数据库驱动 64 java.sql.Connection conn = DriverManager.getConnection(URL, USERNAME, PASSWORD); 65 String sql = "delete sys_users where id=" + id;//编写sql语句 66 PreparedStatement ps = conn.prepareStatement(sql);////创建预处理对象ps 67 ResultSet r = ps.executeQuery(); 68 while (r.next()) { 69 p.setId(r.getInt("id")); 70 p.setName((r.getString("code"))); 71 p.setCode(r.getString("name")); 72 } 73 74 ps.close(); 75 conn.close(); 76 77 } catch (ClassNotFoundException e) { 78 79 e.printStackTrace(); 80 } catch (SQLException e) { 81 e.printStackTrace(); 82 } 83 return p; 84 } 85 86 } View Code

entity：entity目录(实体)，实体就是一个特定的软件模块。

 1 package com.test.entity;
 2 
 3 /**
 4  * Created by wdw on 2017/9/7.
 5  */
 6 public class Person {
 7 
 8     private int id;
 9     private String code;
10     private String name;
11 
12     public int getId() {
13         return id;
14     }
15 
16     public void setId(int id) {
17         this.id = id;
18     }
19 
20     public String getCode(){
21         return  this.code;
22 
23     }
24     public  void  setCode(String code)
25     {
26         this.code=code;
27 
28     }
29     public String getName(){
30         return  this.name;
31 
32     }
33     public  void  setName(String name)
34     {
35         this.name=name;
36 
37     }
38 }

View Code

test：test目录，最终的试行测试。

 1 package com.test.test;
 2 
 3 import com.test.dao.PersonDao;
 4 import com.test.entity.Person;
 5 
 6 /**
 7  * Created by wdw on 2017/9/7.
 8  */
 9 public class test {
10     public static void main(String[] args) {
11         Person ps = new Person();
12         ps.setId(1);
13         ps.setCode("编号");
14         ps.setName("张三");
15         PersonDao s = new PersonDao();
16         boolean aResult = s.insert(ps);  //add a use
17         boolean uResult = s.insert(ps);  //delete a use
18         boolean dResult = s.insert(ps);  //delete a use
19     }
20 
21 }

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4、运行测试，记得在main断点。

 

java 连接mysql增删改查

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