从零开始学JAVA(09)-使用SpringMVC4 + Mybatis + MySql 例子（注解方式开发）

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/dsp?useUnicode=true&characterEncoding=UTF-8
jdbc.username=root
jdbc.password=123456

log4j.rootLogger = debug,stdout

log4j.appender.stdout = org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target = System.out
log4j.appender.stdout.layout = org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern = [%-5p] %d{yyyy-MM-dd HH:mm:ss,SSS} method:%l%n%m%n

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xmlns="http://xmlns.jcp.org/xml/ns/javaee" 
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" 
    id="WebApp_ID" 
    version="3.1">
    
    <!-- 名称随便 -->
    <display-name>mvc mybatis</display-name>

    <!-- 指定servlet -->
    <servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
            <init-param>  
                <param-name>contextConfigLocation</param-name>  
                <param-value>classpath*:springmvc-servlet.xml</param-value>
             </init-param>  
        <load-on-startup>1</load-on-startup>
    </servlet>
  
    <!-- 使用restful风格，所以这里用/ -->
    <servlet-mapping>
       <servlet-name>springmvc</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
            
</web-app>

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:aop="http://www.springframework.org/schema/aop" 
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
        http://www.springframework.org/schema/aop 
        http://www.springframework.org/schema/aop/spring-aop-4.0.xsd 
        http://www.springframework.org/schema/tx  
        http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context-4.0.xsd">
        
    <!-- 指定从配置文件中加载数据库连接信息 -->
    <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="locations">
            <value>classpath:db.properties</value>
        </property>
        <property name="fileEncoding">
            <value>UTF-8</value>
        </property>
    </bean>
    
    <!-- 配置数据源 也可以用dbcp、c3p0数据库连接池等，这里使用Spring默认的 -->
    <!--  
                使用连接池可以提高访问性能，这里可以加入dbcp或c3p0的jar包，并修改class实现
        <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource.class">
    -->        
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="${jdbc.driver}"></property>
        <property name="url" value="${jdbc.url}"></property>
        <property name="username" value="${jdbc.username}"></property>
        <property name="password" value="${jdbc.password}"></property>
    </bean>
       
    <!-- 配置sqlSessionFactory -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <!-- 加载mybatis-config.xml文件 -->
        <property name="configLocation" value="classpath:mybatis-config.xml"></property>
        <!-- 数据源 -->
        <property name="dataSource" ref="dataSource"></property>
    </bean> 
   
    <!-- 扫描包中的mapper类 注意这里使用了sqlSessionFactoryBeanName -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.web.mapper"></property>
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>
    </bean>
    
    
    <!-- 对静态资源文件的访问  -->    
    <mvc:resources mapping="/static/**" location="/static/" cache-period="31556926"/>
    
    <!-- 启用最新的注解解析器、映射器  -->
    <!-- Spring默认情况下使用的是一些旧版本注解解析器、映射器、转换器等 -->
    <mvc:annotation-driven/>    
    
    <!-- 扫描包中所有@Controller注解的类 -->     
    <context:component-scan base-package="com.web.controller" />
    <!-- 扫描包中所有@Service注解的类 -->
    <context:component-scan base-package="com.web.service" />
    
    <!-- 配置视图解析器 -->
    <!--
        prefix和suffix：查找视图页面的前缀和后缀（前缀[逻辑视图名]后缀），
               比如传进来的逻辑视图名为WEB-INF/jsp/hello，则该该jsp视图页面应该存放在“WEB-INF/jsp/hello.jsp”； 
    -->          
    <bean
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix">
            <value>/WEB-INF/jsp/</value>
        </property>
        <property name="suffix">
            <value>.jsp</value>
        </property>
    </bean>
        
</beans>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"   
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>      
    
    <!-- 加载Mapper映射文件 -->
    <mappers>
        <!-- 空着就行，由spring配置加载 -->
    </mappers>
</configuration>

package com.web.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

import com.web.po.User;
import com.web.service.UserService;

@Controller
public class HelloController {
    
    @Autowired
    private UserService userService;
    
    // 建议方法名与url一样，方便维护
    @RequestMapping("/hello") 
    public String hello(@RequestParam(value = "id", required = false, defaultValue = "1") int id,                        
                Model model) throws Exception {                  
            
            // 通过客户端传送过来的id获取user数据
            User user = userService.getUserById(id);
            
            if (user == null) {
                user = new User();
                user.setName("查无记录");
            }
            
            String myhtml = "<div><p>这是html文本。</p><p>红色字体表明css样式文件成功加载。</p><p>这说明jsp上的数据可以由后台控制并显示</P></div><p></P>";
            // 在jsp文件中，可以通过${myhtml}得到myhtml的内容
            model.addAttribute("myhtml", myhtml);
            
            
            model.addAttribute("name", user.getName());            
            
            // 这里去WEB-INF/jsp 中找hello.jsp；因为springmvc-servlet.xml中配置了前缀与后缀，
            // 所以，hello = WEB-INF/jsp/hello.jsp
            return "hello";
    }
}

package com.web.mapper;

import java.util.List;

import com.web.po.User;
/**
 * 
 * @author Lin
 * user表的数据接口
 * mybatis使用mapper代理方式开发时，需要一个接口文件与一个mapper映射文件，并且两个文件名称要相同
 * 这里使用的是UserMapper.java与UserMapper.XML
 */
public interface UserMapper {

    // 获取整个表的数据
    public List<User> getAll() throws Exception;
    
    // 通过表id获取表的数据
    public User getUserById(int id) throws Exception;
}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"   
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">  
<!--
    id与对应接口的某个对应的方法名一致
    mybatic还有其他标签(如<inert><delete>等)，找本书慢慢学
-->
<mapper namespace="com.web.mapper.UserMapper">

    <select id="getdAll" resultType="com.web.po.User"> 
        select * from t_user
    </select>
    
    <select id="getUserById" parameterType="int" resultType="com.web.po.User"> 
        select * from t_user where id=#{id}
    </select>    

</mapper>

package com.web.po;

public class User {
    
    private int id;
    private String gid;
    private String name;
    private String pw;
    
    public int getId() {
        return id;
    }
    
    public void setId(int id) {
        this.id = id;
    }
    
    public String getGid() {
        return gid;
    }
    
    public void setGid(String gid) {
        this.gid = gid;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String name) {
        this.name = name;
    }
    
    public String getPw() {
        return pw;
    }
    
    public void setPw(String pw) {
        this.pw = pw;
    }

}

package com.web.service;

import java.util.List;

import com.web.po.User;

public interface UserService {
    
    // 这里类的接口不需要与UserMapper相同，可以根据业务需要自行定义
    
    // 获取整个表的数据
    public List<User> getAll() throws Exception;
    
    // 通过表id获取表的数据
    public User getUserById(int id) throws Exception;

}

package com.web.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.web.mapper.UserMapper;
import com.web.po.User;

/**
 * 
 * @author Lin
 * @Service 注解 表此类是一个服务，服务一般由一个接口与一个接口实现类组成
 * 非注解方式开发，还需要spring的xml中配置才能使用，此处用的是注解方式，不需要额外配置
 */

@Service
public class UserServiceImpl implements UserService {

    // 注入msbatis数据库访问接口
    @Autowired
    private UserMapper userMapper;
    
    @Override
    public List<User> getAll() throws Exception {
        // TODO Auto-generated method stub
        // 这里不写了 如果想在jsp中显示list，可以引入jstl标签进行操作显示，记得加入jstl的包 jstl-1.2.jar
        return null;
    }

    @Override
    public User getUserById(int id) throws Exception {
        // TODO Auto-generated method stub
        
        // 通过userMapper获取数据
        User user = userMapper.getUserById(id);        
        return user;
    }

}

body {
    font-size: 36px;
    color: #FF0000;
}

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<!-- 这里指定css样式，是为了检查配置的静态文件的访问是否成功 -->
<link rel="Stylesheet" type="text/css" href="static/style.css" />
<title>SpringMVC + Mybatic</title>
</head>
<body>
${myhtml}

hello，${name}
</body>
</html>