Spring整合Web开发需要导入的坐标
<properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <maven.compiler.source>11</maven.compiler.source> <maven.compiler.target>11</maven.compiler.target> </properties>
<build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.8.1</version> <configuration> <release>11</release> </configuration> </plugin> </plugins> </build>
<dependencies> <!-- 下面是web开发需要的依赖--> <dependency> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> <version>3.1.0</version> </dependency> <!-- 下面是spring依赖--> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>4.2.4.RELEASE</version> </dependency> <!-- 下面两个是spring整和Web需要的坐标--> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> <scope>provided</scope> </dependency> <dependency> <groupId>Maven_Repository.javax.servlet.jsp</groupId> <artifactId>javax.servlet.jsp-api</artifactId> <version>2.3.1</version> <scope>provided</scope> </dependency> <!-- 下面是上下文应用整和的坐标--> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>5.0.5.RELEASE</version> </dependency> <dependency> <groupId>Maven_Repository.com.h2database</groupId> <artifactId>h2</artifactId> <version>1.3.158</version> </dependency> </dependencies>
① 配置ContextLoaderListener监听器
② 使用WebApplicationContextUtils获得应用上下文
获取ApplicationContext对象是从servletContext域中获取的，还有就是使用WebApplicationContextUtils获取app。 可以直接从Spring获取app对象，省去了自己创建。还有就是以后要使用到多次app对象，所以就是省去了new出多了app对象。
dao层代码
package com.itheima.dao.impl; import com.itheima.dao.UserDao; public class UserDaoImpl implements UserDao { public void save() { System.out.println("save is running"); } }
service层代码
package com.itheima.service.impl; import com.itheima.dao.UserDao; import com.itheima.service.UserService; public class UserServiceImpl implements UserService { private UserDao userDao; public void setUserDao(UserDao userDao) { this.userDao = userDao; } public void save() { userDao.save(); } }
web层
package com.itheima.web; import com.itheima.service.UserService; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.web.context.WebApplicationContext; import org.springframework.web.context.support.WebApplicationContextUtils; import javax.servlet.ServletContext; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; @WebServlet("/servlet") public class UserServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { // ApplicationContext app = new ClassPathXmlApplicationContext("applicationContext.xml"); ServletContext servletContext = this.getServletContext(); // ApplicationContext app = (ApplicationContext) servletContext.getAttribute("app"); // ApplicationContext app = WebApplicationContextUtils.getWebApplicationContext(servletContext); ApplicationContext app = WebApplicationContextUtils.getWebApplicationContext(servletContext); UserService userService = (UserService) app.getBean("userService"); userService.save(); } }
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" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> <bean id="userDao" class="com.itheima.dao.impl.UserDaoImpl"></bean> <bean id="userService" class="com.itheima.service.impl.UserServiceImpl"> <property name="userDao" ref="userDao"></property> </bean> </beans>
web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version="4.0"> <!--全局初始化参数--> <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> </web-app>
问题：
在配置maven时候，project下面有红色波浪线的话，可能是复制的坐标，需要重写写一遍，还有就是是maven可能是3.6.3版本，idea和maven可能会出现冲突，所以要降低maven版本，改为3.6.1版本即可。
在部署tomcat的时候，可能回出现监听器的问题，如果是tomcat10，就需要降低tomcat版本，如果是tomcat8.5.5及其一下的版本，就需要做一下操作。
就会出现lib包，再重新部署一下项目就可以了。
