一 建立一个WEB项目,然后就是一些jar包的引入,如下图
二 除了以上基本的spring jar包,还需要mybatis和spring整合包,数据库连接池以及springmvc,如下图
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>5.2.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>5.2.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>5.3.5</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.commons/commons-dbcp2 -->
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-dbcp2</artifactId>
<version>2.2.0</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.commons/commons-pool2 -->
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-pool2</artifactId>
<version>2.4.2</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>2.0.2</version>
</dependency>
在资源包下建立数据库常量配置文件db.properties,spring配置文件applicationContext.xml,Mybatis配置文件mybatis-config.xml,以及springmvc配置文件springmvc-config.xml。
1.applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx.xsd">
<!--读取db.properties-->
<context:property-placeholder location="classpath:db.properties"/>
<!-- 配置数据源-->
<bean id="dataSource" class="org.apache.commons.dbcp2.BasicDataSource">
<!-- 数据库驱动-->
<property name="driverClassName" value="${jdbc.driver}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
<property name="maxTotal" value="${jdbc.maxTotal}"/>
<property name="maxIdle" value="${jdbc.maxIdle}"/>
<property name="initialSize" value="${jdbc.initialSize}"/>
</bean>
<!-- 事务管理器-->
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"></property>
</bean>
<!--注册事务管理器驱动,开启事务注解-->
<tx:annotation-driven transaction-manager="transactionManager"/>
<!-- 配置mybatis工厂-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<!-- 注入数据源-->
<property name="dataSource" ref="dataSource"/>
<!--指定核心配置文件位置-->
<property name="configLocation" value="classpath:mybatis-config.xml"/>
</bean>
<!--配置mapper扫描器-->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.ssm.dao"></property>
</bean>
<!-- 扫描service-->
<context:component-scan base-package="com.ssm.service"/>
</beans>
2.mybatis-config.xml
<?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>
<!--配置别名-->
<typeAliases>
<package name="com.ssm.po"/>
</typeAliases>
</configuration>
3.springmvc-config.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd
http://www.springframework.org/schema/context ">
<!-- 指定需要扫描的包-->
<context:component-scan base-package="com.ssm.controller"/>
<!-- 配置注解驱动-->
<mvc:annotation-driven/>
<!-- 定义视图解析器-->
<bean id="ViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!-- 设置前缀-->
<property name="prefix" value="/jsp/"/>
<!-- 设置后缀-->
<property name="suffix" value=".jsp"/>
</bean>
</beans>
4.包结构如下
public class User {
private Integer id;
private String username;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
```java
public interface UserDao {
public User findUserById(Integer id);
}
public interface UserService {
public User findUserById(Integer id);
}
//userdao的mapper映射文件
<?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" >
<mapper namespace="com.ssm.dao.UserDao">
<select id="findUserById" parameterType="Integer" resultType="User">
select * from t_user where id=#{id}
</select>
</mapper>
@Service
//标识类中所有方法纳入spring事务管理
@Transactional
public class UserServiceImp implements UserService {
@Autowired
private UserDao userDao;
@Override
public User findUserById(Integer id) {
//查询客户
return this.userDao.findUserById(id);
}
}
@Controller
public class UserController {
@Autowired
private UserService userService;
@RequestMapping("/findUserById")
public String findUserById(Integer id, Model model){
User user=userService.findUserById(id);
model.addAttribute("user",user);
//返回用户信息展示页面
return "user";
}
}
5.web.xml的配置
!-- 配置加载spring文件的监听器-->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:applicationContext.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- 编码过滤器-->
<filter>
<filter-name>encoding</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encoding</filter-name>
<url-pattern>*.action</url-pattern>
</filter-mapping>
<!-- 配置springmvc前端控制器-->
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<!-- 初始化加载配置文件-->
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:springmvc-config.xml</param-value>
</init-param>
<!-- 配置服务器时立即加载SPRINGMVC文件-->
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<!-- /拦截所有请求,jsp除外-->
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
6.创建一个名为jsp的文件夹,创建一个user.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
<title>用户信息</title>
</head>
<body>
<table>
<tr>
<td>用户ID</td>
<td>${user.id}</td>
</tr>
<tr>
<td>用户姓名</td>
<td>${user.username}</td>
</tr>
</table>
</body>
</html>
7.发布到tomca服务器上结果如下
三 总结可能会遇到的问题:
1.一个或多个listeners启动失败,web application 找不到此类,所以要在web下创建lib文件引入jar包 ,在IDEA中点击File > Project Structure > Artifacts > 在右侧Output Layout右击项目名,选择Put into Output Root。
执行后,在WEB-INF在增加了lib目录,里面是项目引用的jar包,点击OK。
2.http500错误,由于mapper映射文件没有被扫描到。
此异常的原因是由于mapper接口编译后在同一个目录下没有找到mapper映射文件而出现的。由于maven工程在默认情况下src/main/java目录下的mapper文件是不发布到target目录下的。
在pom下写入
src/main/java
/*.properties
/*.xml
false