Spring与Web

一、定义页面及Servlet

在jsp页面加入以下，避免乱码

<meta charset="utf-8">

<body>
    <form action="RegisterServlte" method="post">
        姓名：<input type="text" name="name" /><br> 
        年龄：<input type="text" name="age" /><br> 
        <input type="submit" value="注册" />
    </form>
  </body>

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.jmu.beans.Student;

/**
 * Servlet implementation class RegisterServlte
 */
public class RegisterServlte extends HttpServlet {
    private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doPost(request, response);
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        request.setCharacterEncoding("utf-8");
        String name=request.getParameter("name");
        String ageStr=request.getParameter("age");
        Integer age=Integer.valueOf(ageStr);
        Student student=new Student(name,age);

        request.getRequestDispatcher("/welcome.jsp").forward(request, response);
    }

}

三、测试环境搭建

 1 public class Student {
 2     private Integer id;
 3     private String name;
 4     private int age;
 5 
 6     
 7     public Student() {
 8         super();
 9     }
10 
11     public Student( String name, int age) {
12         super();
13         this.name = name;
14         this.age = age;
15     }
16 
17     public Integer getId() {
18         return id;
19     }
20 
21     public void setId(Integer id) {
22         this.id = id;
23     }
24 
25     public String getName() {
26         return name;
27     }
28 
29     public void setName(String name) {
30         this.name = name;
31     }
32 
33     public int getAge() {
34         return age;
35     }
36 
37     public void setAge(int age) {
38         this.age = age;
39     }
40 
41     @Override
42     public String toString() {
43         return "Student [id=" + id + ", name=" + name + ", age=" + age + "]";
44     }
45 
46 }

Student

 1 //Dao增删改查
 2 public interface IStudentDao {
 3     void insertStudent(Student student);
 4     void deleteById(int id);
 5     void updateStudent(Student student);
 6 
 7 
 8     List<Student> selectAllStudents();
 9     Student selectStudentById(int id);
10 }

IStudentDao

 1 <?xml version="1.0" encoding="UTF-8" ?>
 2 <!DOCTYPE mapper
 3 PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
 4 "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
 5 <mapper namespace="com.jmu.dao.IStudentDao">
 6     <insert id="insertStudent">
 7         insert into student(name,age) values(#{name},#{age})
 8     </insert>
 9 
10     <delete id="deleteById">
11         delete from student where id=#{XXX}
12     </delete>
13 
14     <update id="updateStudent">
15         update student set name=#{name},age=#{age} where id=#{id}
16     </update>
17 
18     <select id="selectAllStudents" resultType="student">
19         select id,name,age from student
20     </select>
21 
22     <select id="selectStudentById" resultType="student">
23         select id,name,age from student where id=#{XXX}
24     </select>
25 </mapper>

IStudentDao.xml

IStudentService

 1 public class StudentServiceImpl implements IStudentService {
 2     private IStudentDao dao;
 3 
 4     public void setDao(IStudentDao dao) {
 5         this.dao = dao;
 6     }
 7 
 8 
 9     public void addStudent(Student student) {
10         // TODO Auto-generated method stub
11         dao.insertStudent(student);
12 
13     }
14 
15     
16     public void removeById(int id) {
17         // TODO Auto-generated method stub
18         dao.deleteById(id);
19     }
20 
21     
22     public void modifyStudent(Student student) {
23         // TODO Auto-generated method stub
24         dao.updateStudent(student);
25     }
26 
27     
28     public List<String> findAllStudentsNames() {
29         // TODO Auto-generated method stub
30         List<String> names = new ArrayList<String>();
31         List<Student> sudents = this.findAllStudents();
32         for (Student student : sudents) {
33           names.add(student.getName());
34         }
35         return names;
36     }
37 
38     
39     public String findStudentNameById(int id) {
40         // TODO Auto-generated method stub
41         Student student = this.findStudentById(id);
42         return student.getName();
43     }
44 
45     
46     public List<Student> findAllStudents() {
47         // TODO Auto-generated method stub
48         return dao.selectAllStudents();
49     }
50 
51     
52     public Student findStudentById(int id) {
53         // TODO Auto-generated method stub
54         return dao.selectStudentById(id);
55     }
56 
57 }

StudentServiceImpl

// 获取Spring容器对象
        ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml");
        // 从Spring容器中获取到service对象
        IStudentService service = (IStudentService) ac.getBean("studentService");
        // 调用Service的addStudent()完成插入
        service.addStudent(student);

RegisterServlet

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
 4     xsi:schemaLocation="
 5         http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
 6         http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
 7 
 8 
 9     <!--注册数据源:C3P0 -->
10     <bean id="myDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
11         <property name="driverClass" value="${jdbc.driver}" />
12         <property name="jdbcUrl" value="${jdbc.url}" />
13         <property name="user" value="${jdbc.user}" />
14         <property name="password" value="${jdbc.password}" />
15     </bean>
16 
17     <!-- 注册属性文件 -->
18     <context:property-placeholder location="classpath:jdbc.properties" />
19     
20     <bean id="mySqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
21        <property name="configLocation" value="classpath:mybatis.xml"></property>
22        <property name="dataSource" ref="myDataSource"></property>
23     </bean>
24     
25     
26     <!--生成Dao的代理对象 
27      当前配置会被本包中所有的接口生成代理对象
28     -->
29     <bean  class="org.mybatis.spring.mapper.MapperScannerConfigurer">
30         <property name="sqlSessionFactoryBeanName" value="mySqlSessionFactory" />
31         <property name="basePackage" value="com.jmu.dao" />
32     </bean>
33 
34     <!-- 注册Service -->
35     <bean id="studentService" class="com.jmu.service.StudentServiceImpl">
36          <!-- 这里的Dao的注入需要使用ref属性，且其作为接口的简单类名 -->
37         <property name="dao" ref="IStudentDao" />
38     </bean>
39 </beans>

applicationContext.xml

 1 <?xml version="1.0" encoding="UTF-8" ?>
 2 <!DOCTYPE configuration
 3 PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
 4 "http://mybatis.org/dtd/mybatis-3-config.dtd">
 5 <configuration>
 6 
 7     <!--配置别名 -->
 8     <typeAliases>
 9         <package name="com.jmu.beans" />
10     </typeAliases>
11 
12     <mappers>
13         <package name="com.jmu.dao" />
14     </mappers>
15 
16 </configuration>

mybatis.xml

四、当前程序存在问题

刷新会创建不同spring容器对象，而不同servlet创建不同容器。当一个应用只能有一个spring容器

五、注册ContextLoaderListener

复制之前web项目，需要修改web context root

ctrl+shift+t open Type
ctrl+o 查看结构
ctrl+t 查看继承关系

myeclipse快捷键

方法一：读源码ContextLoaderListener与ContextLoader获取key

注册ServletContext监听器，完成2件工作：

1、在Servletcontext被创建时，创建Spring容器对象；

2、将创建好的Spring容器对象放入到ServletContext的域属性空间

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
 </listener>

修改applicationContext.xml为spring.xml在web.xml中添加如下(Spring在web项目中必须有的2项配置)：

 <context-param>
    <param-name>contextConfigLocation </param-name>
    <param-value>classpath:spring.xml</param-value>
  </context-param>
<!--   注册servletContext监听器 -->
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>

修改servlet中

    // 获取Spring容器对象
        String acKey = WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE;
        ApplicationContext ac = (ApplicationContext) this.getServletContext().getAttribute(acKey);

 1 public class RegisterServlet extends HttpServlet {
 2     private static final long serialVersionUID = 1L;
 3 
 4     /**
 5      * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
 6      *      response)
 7      */
 8     protected void doGet(HttpServletRequest request, HttpServletResponse response)
 9             throws ServletException, IOException {
10         // TODO Auto-generated method stub
11         doPost(request, response);
12     }
13 
14     /**
15      * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
16      *      response)
17      */
18     protected void doPost(HttpServletRequest request, HttpServletResponse response)
19             throws ServletException, IOException {
20         // TODO Auto-generated method stub
21         request.setCharacterEncoding("utf-8");
22         String name = request.getParameter("name");
23         String ageStr = request.getParameter("age");
24         Integer age = Integer.valueOf(ageStr);
25         Student student = new Student(name, age);
26         // 获取Spring容器对象
27         String acKey = WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE;
28         ApplicationContext ac = (ApplicationContext) this.getServletContext().getAttribute(acKey);
29         // 从Spring容器中获取到service对象
30         IStudentService service = (IStudentService) ac.getBean("studentService");
31         // 调用Service的addStudent()完成插入
32         service.addStudent(student);
33         request.getRequestDispatcher("/welcome.jsp").forward(request, response);
34     }
35 
36 }

RegisterServlet

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
 3   <display-name>17-spring-web</display-name>
 4   <welcome-file-list>
 5     <welcome-file>index.jsp</welcome-file>
 6   </welcome-file-list>
 7   
 8   <context-param>
 9     <param-name>contextConfigLocation </param-name>
10     <param-value>classpath:spring.xml</param-value>
11   </context-param>
12 <!--   注册servletContext监听器 -->
13   <listener>
14     <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
15   </listener>
16   <servlet>
17     <description></description>
18     <display-name>RegisterServlet</display-name>
19     <servlet-name>RegisterServlet</servlet-name>
20     <servlet-class>com.jmu.servlets.RegisterServlet</servlet-class>
21   </servlet>
22   <servlet-mapping>
23     <servlet-name>RegisterServlet</servlet-name>
24     <url-pattern>/RegisterServlet</url-pattern>
25   </servlet-mapping>
26   <servlet>
27     <description></description>
28     <display-name>LoginServlet</display-name>
29     <servlet-name>LoginServlet</servlet-name>
30     <servlet-class>com.jmu.servlets.LoginServlet</servlet-class>
31   </servlet>
32   <servlet-mapping>
33     <servlet-name>LoginServlet</servlet-name>
34     <url-pattern>/LoginServlet</url-pattern>
35   </servlet-mapping>
36 </web-app>

web.xml

方法二：使用工具类获取Spring容器

修改servlet中

    // 获取Spring容器对象
        WebApplicationContext ac= WebApplicationContextUtils.getRequiredWebApplicationContext(getServletContext());

posted @ 2018-03-08 19:55 honghj 阅读(288) 评论(0) 编辑收藏举报

刷新页面返回顶部

honghj

Spring与Web

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