Sping IOC容器

Sping IOC容器

package servlet;

import org.springframework.context.ApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import service.IStudentService;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import java.io.IOException;

@WebServlet("/QueryStudentByIdServlet")
public class QueryStudentByIdServlet extends javax.servlet.http.HttpServlet {
    private IStudentService studentService;

    public void setStudentService(IStudentService studentService) {
        this.studentService = studentService;
    }

    @Override
    public void init() throws ServletException {
        super.init();
        ApplicationContext applicationContext = WebApplicationContextUtils.getWebApplicationContext(this.getServletContext());
        studentService = (IStudentService) applicationContext.getBean("studentServiceId");
    }

    protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)
            throws javax.servlet.ServletException, IOException {
        String name = studentService.queryStudentById();
        request.setAttribute("name", name);
        request.getRequestDispatcher("result.jsp").forward(request, response);
    }

    protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)
            throws javax.servlet.ServletException, IOException {
        doGet(request, response);
    }
}

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_3_1.xsd"
         version="3.1">
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:applicationContext.xml, classpath:applicationContext-*.xml</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
</web-app>

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 http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
    
</beans>

applicationContext-Controller.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="studentServlet" class="servlet.QueryStudentByIdServlet">
        <property name="studentService" ref="studentServiceId">  </property>
    </bean>
</beans>

applicationContext-Service.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="studentServiceId" class="service.impl.StudentServiceImpl">
        <property name="studentDao" ref="studentDaoId"></property>
    </bean>
</beans>

applicationContext-Dao.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="studentDaoId" class="dao.impl.StudentDaoImpl"></bean>
</beans>