MySql连接及数据的传输例子
1.首先建立数据库
2.导入JDBC，beanutil单元测试包
3.javaBean类(和数据库列相同，最好列名相同)
package com.dp.web.domain;
import java.io.Serializable;
import java.util.Date;
public class Customer implements Serializable {
private String id ;
private String name ;
private String gender ;
private Date birthday;
private String cellphone ;
private String email ;
private String hobby ;
private String type ;
private String description ;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getCellphone() {
return cellphone;
}
public void setCellphone(String cellphone) {
this.cellphone = cellphone;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getHobby() {
return hobby;
}
public void setHobby(String hobby) {
this.hobby = hobby;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
}
4.连接数据库的工具文件
先准备db.properties文件，这个主要是用来保存数据库的连接信息（库名,用户,密码），以便在连接工具来的时候可以多次使用.
DriverclassName=com.mysql.jdbc.Driver url=jdbc:mysql://localhost:3306/day15 user=root password=root建立连接工具类(在这个中就可以读取上面那个文件信息了)
package com.dp.web.util;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
public class JdbcUtil {
private static String DriverclassName;
private static String password;
private static String url;
private static String user;
static{
//读取配置文件，将其中的文件读取出来用
InputStream in=JdbcUtil.class.getClassLoader().getResourceAsStream("db.properties");
Properties pro=new Properties();
try {
pro.load(in);
DriverclassName=pro.getProperty("DriverclassName");
password=pro.getProperty("password");
url=pro.getProperty("url");
user=pro.getProperty("user");
Class.forName(DriverclassName);//注册一次就可以了
} catch (Exception e) {
e.printStackTrace();
}
}
public static Connection getConnection() throws Exception{
return DriverManager.getConnection(url,user, password);
}
public static void release(ResultSet rs,Statement stmt,Connection c){
if(rs!=null){
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
rs=null;
}
if(stmt!=null){
try {
stmt.close();
} catch (SQLException e) {
e.printStackTrace();
}
stmt=null;
}
if(c!=null){
try {
c.close();
} catch (SQLException e) {
e.printStackTrace();
}
c=null;
}
}
}
5.dao接口层(增删改查)
package com.dp.web.dao;
import java.util.List;
import com.dp.web.domain.Customer;
import com.dp.web.exception.IdIsNullException;
public interface CustomerDao {
/**
* @param addCustomer
* 添加客户信息
*/
void addCustomer(Customer c);
/**
* 根据ID删除客户信息
* @param customerId
*/
void delCustomerById(String customerId);
/**
* 更新客户的信息
* 如果更新的客户的ID为null
* 则出现异常
* @param c
* @throws IdIsNullException
*/
void updateCustomer(Customer c) throws IdIsNullException;
/**
* @return
* 查询客户所有的信息
*/
List<Customer> findAll();
/**
* 根据客户的id查询客户信息
* @param customerId
* @return
*/
Customer findCustomerById(String customerId);
}
6.dao实现层（增删改查数据处理）
package com.dp.web.dao.iml;
import java.sql.Connection;
import java.sql.Date;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;
import com.dp.web.dao.CustomerDao;
import com.dp.web.domain.Customer;
import com.dp.web.exception.DaoException;
import com.dp.web.exception.IdIsNullException;
import com.dp.web.util.JdbcUtil;
public class CustomerDaoImp implements CustomerDao {
@Override
public void addCustomer(Customer c) {
if(c==null)
throw new IllegalArgumentException();
Connection conn=null;
PreparedStatement stam=null;
ResultSet resu=null;
try{
conn=JdbcUtil.getConnection();
stam=conn.prepareStatement("insert into customer (id,name,gender,birthday,cellphone,email,hobby,type,description) value(?,?,?,?,?,?,?,?,?)");
stam.setString(1, c.getId());
stam.setString(2, c.getName());
stam.setString(3, c.getGender());
stam.setDate(4, new java.sql.Date(c.getBirthday().getTime()));
stam.setString(5, c.getCellphone());
stam.setString(6, c.getEmail());
stam.setString(7, c.getHobby());
stam.setString(8, c.getType());
stam.setString(9, c.getDescription());
stam.executeUpdate();//更新到数据库
}catch(Exception e){
throw new DaoException();
}finally{
JdbcUtil.release(resu, stam, conn);
}
}
@Override
public void delCustomerById(String customerId) {
if(customerId==null)
throw new IllegalArgumentException();
Connection conn=null;
PreparedStatement stam=null;
ResultSet resu=null;
try{
conn=JdbcUtil.getConnection();
stam=conn.prepareStatement("delete from customer where id=?");
stam.setString(1, customerId);
stam.executeUpdate();//更新到数据库
}catch(Exception e){
throw new DaoException();
}finally{
JdbcUtil.release(resu, stam, conn);
}
}
@Override
public void updateCustomer(Customer c) throws IdIsNullException {
if(c==null)
throw new IllegalArgumentException();
if(c.getId()==null)
throw new IdIsNullException("this customer's ID cant't null");
Connection conn=null;
PreparedStatement stam=null;
ResultSet resu=null;
try{
conn=JdbcUtil.getConnection();
stam=conn.prepareStatement("update customer set name=?,gender=?,birthday=?,cellphone=?,email=?,hobby=?,type=?,description=? where id=?");
stam.setString(1, c.getName());
stam.setString(2, c.getGender());
stam.setDate(3, new java.sql.Date(c.getBirthday().getTime()));
stam.setString(4, c.getCellphone());
stam.setString(5, c.getEmail());
stam.setString(6, c.getHobby());
stam.setString(7, c.getType());
stam.setString(8, c.getDescription());
stam.setString(9, c.getId());
stam.executeUpdate();//更新到数据库
}catch(Exception e){
throw new DaoException();
}finally{
JdbcUtil.release(resu, stam, conn);
}
}
@Override
public List<Customer> findAll() {
Connection conn=null;
PreparedStatement stam=null;
ResultSet resu=null;
List<Customer> cs=new ArrayList<Customer>();
try{
conn=JdbcUtil.getConnection();
stam=conn.prepareStatement("select id,name,gender,birthday,cellphone,email,hobby,type,description from customer");
resu=stam.executeQuery();
while(resu.next()){
Customer c=new Customer();
c.setId(resu.getString("id"));
c.setName(resu.getString("name"));
c.setGender(resu.getString("gender"));
c.setBirthday(resu.getDate("birthday"));
c.setCellphone(resu.getString("cellphone"));
c.setEmail(resu.getString("email"));
c.setHobby(resu.getString("hobby"));
c.setType(resu.getString("type"));
c.setDescription(resu.getString("description"));
cs.add(c);
}
return cs;
}catch(Exception e){
throw new DaoException();
}finally{
JdbcUtil.release(resu, stam, conn);
}
}
@Override
public Customer findCustomerById(String customerId) {
if(customerId==null)
throw new IllegalArgumentException();
Connection conn=null;
PreparedStatement stam=null;
ResultSet resu=null;
try{
conn=JdbcUtil.getConnection();
stam=conn.prepareStatement("select id,name,gender,birthday,cellphone,email,hobby,type,description from customer where id=?");
stam.setString(1, customerId);
resu=stam.executeQuery();
if(resu.next()){
Customer c=new Customer();
c.setId(resu.getString("id"));
c.setName(resu.getString("name"));
c.setGender(resu.getString("gender"));
c.setBirthday(resu.getDate("birthday"));
c.setCellphone(resu.getString("cellphone"));
c.setEmail(resu.getString("email"));
c.setHobby(resu.getString("hobby"));
c.setType(resu.getString("type"));
c.setDescription(resu.getString("description"));
return c;
}
return null;
}catch(Exception e){
throw new DaoException();
}finally{
JdbcUtil.release(resu, stam, conn);
}
}
}
测试层：(开发中不需要这个，这个只是用来测试的)
package com.dp.web.test;
import static org.junit.Assert.*;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.UUID;
import org.junit.Test;
import com.dp.web.dao.CustomerDao;
import com.dp.web.dao.iml.CustomerDaoImp;
import com.dp.web.domain.Customer;
import com.dp.web.exception.IdIsNullException;
/**
* @author Administrator
* Customer访问数据库的单元测试/只是用来测试是否正确的
*
*/
public class CustomerDaoImpTest {
private CustomerDao dao=new CustomerDaoImp();
//id,name,gender,birthday,cellphone,email,hobby,type,description
@Test
public void testAddCustomer() {
Customer c=new Customer();
//加数据
// c.setId(UUID.randomUUID().toString());
c.setId("1");
c.setName("Mr_Li13");
c.setGender("0");//0代表男人
c.setBirthday(new Date());
c.setCellphone("55555686");
c.setEmail("[email protected]");
c.setHobby("网球");
c.setType("VIP");
c.setDescription("他是男人");
//将对象放到dao接口实现的对象中
dao.addCustomer(c);
}
@Test
public void testDelCustomerById() {
dao.delCustomerById("143a380a-8a4a-486f-9e9d-070bfe616b6e");
}
@Test(expected=com.dp.web.exception.IdIsNullException.class)
public void testUpdateCustomer() throws IdIsNullException {
Customer c=new Customer();
dao.updateCustomer(c);
//如果显示绿色说明测试异常
//下面那个测试才是update的测试
}
@Test
public void testUpdateCustomer1() throws IdIsNullException{
Customer c=dao.findCustomerById("143a380a-8a4a-486f-9e9d-070bfe616b6e");
c.setGender("0");
dao.updateCustomer(c);
}
@Test
public void testFindAll() {
List<Customer> list1=dao.findAll();
assertEquals(1, list1.size());
// for(int i=0;i<list1.size();i++){
// System.out.println(list1.get(i));
// }
// Iterator t=list1.iterator();
// while(t.hasNext()){
// System.out.println(t.next());
// }
// for(Object s:list1){
// System.out.println(s);
// }
}
@Test
public void testFindCustomerById() {
Customer c=dao.findCustomerById("143a380a-8a4a-486f-9e9d-070bfe616b6e");
assertNotNull(c);
//上面这个是测试有结果的，下面这个是测试没有结果的
c=dao.findCustomerById("2");
assertNull(c);
}
}
这就是写数据库到dao的过程，如果写mvc的话，service接口层的方法可以暂时和dao接口层的方法相同，因为规则是这样的，后续的可以慢慢添加。
在我的资源中有一个资源可以共享，主要是用户信息封装到数据库，采用mvc结构+三层架构。
连接：http://download.csdn.net/detail/mr_li13/9191051