springmvc註解項目開發流程

1. 概述

本篇主要介紹如何通過註解來實現springmvc的項目開發。

參考博客：《SpringMVC學習（二）——快速搭建SpringMVC開發環境（註解方式）》

博客內容跟簡潔，源碼：https://gitee.com/leo825/spring-framework-learning-example

1.1 開發環境簡述

本篇主要使用vscode遠程開發模式。

遠程主機

遠程主機(虛擬機centos7.9)部署java開發環境：

#jdk環境
export JAVA_HOME=/opt/javaenv/jdk-17
export PATH=$JAVA_HOME/bin:$PATH
#tomcat環境
export PATH=/opt/javaenv/apache-tomcat-8.5.81/bin:$PATH
#maver環境
export PATH=/opt/javaenv/apache-maven-3.8.6/bin:$PATH

項目位置：/home/liwl/Documents/nsccwx/liwldev/java/web/springmvc/

項目創建命令：mvn archetype:generate -DgroupId=com.liwl.java -DartifactId=liwl_springmvc_annotation -DarchetypeArtifactId=maven-archetype-webapp -DinteractiveMode=false

本地工具

本地使用的操作系統(win10/deepin20.6)，代碼編輯器vscode.1.69.0

vscode插件：java開發相關插件，Maven for java，Community Server Connectors

2. 開發過程

2.1 maven創建項目

進入到項目位置：cd /home/liwl/Documents/nsccwx/liwldev/java/web/springmvc/

創建項目：mvn archetype:generate -DgroupId=com.liwl.java -DartifactId=liwl_springmvc_annotation -DarchetypeArtifactId=maven-archetype-webapp -DinteractiveMode=false

使用vscode遠程管理功能，連接遠程主機後，打開目錄：/home/liwl/Documents/nsccwx/liwldev/java/web/springmvc/liwl_springmvx_annotation即可進行開發

2.2 pom.xml引入項目依賴

編輯pom.xml，引入依賴包：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.liwl.java</groupId>
  <artifactId>liwl_springmvc_annotation</artifactId>
  <packaging>war</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>liwl_springmvc_annotation Maven Webapp</name>
  <url>http://maven.apache.org</url>

  <properties>
    <spring.version>5.3.21</spring.version>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>17</maven.compiler.source>
    <maven.compiler.target>17</maven.compiler.target>
  </properties>

  <dependencies>

    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>3.0.1</version>
    </dependency>

    <dependency>
      <groupId>javax.servlet.jsp</groupId>
      <artifactId>jsp-api</artifactId>
      <version>2.2</version>
      <scope>provided</scope>
    </dependency>

  </dependencies>

  <build>
    <finalName>liwl_springmvc_annotation</finalName>
    <pluginManagement>
      <plugins>
        <plugin>
          <artifactId>maven-clean-plugin</artifactId>
          <version>3.1.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-resources-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.8.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.22.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-war-plugin</artifactId>
          <version>3.2.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-install-plugin</artifactId>
          <version>2.5.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-deploy-plugin</artifactId>
          <version>2.8.2</version>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>
</project>

2.3 web.xml配置項目

編輯web.xml，配置項目，其內容如下：

<?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">
  <display-name>Archetype Created Web Application</display-name>

  <servlet>
    <servlet-name>liwl_springmvc_by_xml</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:liwl-springmvc-servlet.xml</param-value>
    </init-param>
  </servlet>

  <servlet-mapping>
    <servlet-name>liwl_springmvc_by_xml</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

</web-app>

web.xml裏面通過contextConfigLocation參數，引入了liwl-springmvc-servlet.xml配置，在resources目錄下創建liwl-springmvc-servlet.xml

2.4 liwl-springmvc-servlet.xml配置

在resources目錄下創建liwl-springmvc-servlet.xml，其內容如下：

需要注意的是xmlns的配置，如果配置有問題，則無法識別mvc標籤

<?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-3.0.xsd 
       http://www.springframework.org/schema/mvc 
       http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd 
       http://www.springframework.org/schema/context 
       http://www.springframework.org/schema/context/spring-context.xsd"
       default-lazy-init="true">

    <!-- 處理器映射器，將處理器Handler的name作爲URL進行查找 -->
    <bean class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"></bean>

    <!-- 處理器適配器，適配處理器中handlerRequest方法的調用 -->
    <bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter"></bean>

    <!-- 配置視圖解析器，把handler方法返回的邏輯視圖解析爲實際的物理視圖 -->
    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/views/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

    <mvc:annotation-driven></mvc:annotation-driven>
    <context:component-scan base-package="com.liwl"></context:component-scan>
</beans>

2.5 編寫HelloController.java

在src/main/目錄下創建java/com/liwl/controller目錄

在controller目錄下創建HelloController.java，其內容如下：

package com.liwl.controller;

import java.io.IOException;

import javax.servlet.ServletException;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

@Controller
public class HelloController {

    @RequestMapping(value = "/hello",method = RequestMethod.GET)
    public ModelAndView hello() throws ServletException,IOException{
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.addObject("data","springmvc註解編碼測試成功");
        modelAndView.setViewName("success");
        return modelAndView;
    }
}

2.6 編寫success.jsp文件

在webapp/WEB-INF/目錄下創建views目錄，在views目錄下創建success.jsp文件，其內容如下：

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<body>
<h2>跳轉到success了!!!</h2>
    <p>
        ${data}
    </p>
</body>
</html>

2.7 運行測試

在vscode裏面，右鍵項目maven插件，執行packages命令，生成target目錄，在target目錄下，生成了liwl_springmvc_annotation.war文件

右鍵項目SERVERS插件，添加Tomcat服務。根據遠程主機Tomcat的部署位置，添加好Community Server Connector的Tomcat服務，右鍵start啓動Tomcat服務。

右鍵liwl_springmvc_annotation.war，執行Run on server

最後瀏覽器訪問：http://localhost:8080/liwl_springmvc_annotation/hello

需要配置端口轉發。點擊端口->添加端口，輸入8080，回車。即可把遠程主機的8080端口轉發到本地的8080

2.8 數據庫服務配置部分

修改pom.xml，增加以下內容，引入數據庫依賴：

注意mysql-connector-java不加 <scope>provided</scope>

<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-jdbc</artifactId>
  <version>${spring.version}</version>
</dependency>

<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
  <version>8.0.29</version> 
</dependency>

2.9 數據庫服務編碼部分

2.9.0 初始化項目目錄

在src/main/java目錄下創建com/liwl/{control,service,model,util}目錄，在src/main/java/com/liwl/service/目錄下創建impl目錄

[root@node98][~/liwldev/java/web/springmvc/liwl_springmvc_annotation/src]
$ tree -d -L 5
.
└── main
    ├── java
    │   └── com
    │       └── liwl
    │           ├── controller
    │           ├── model
    │           ├── servcie
    │           └── util
    ├── resources
    └── webapp
        └── WEB-INF
            └── views

2.9.1 創建model下UserInfo.java

package com.liwl.model;

public class UserInfo {

    private Long id;
    private String name;
    private String age;
    private String gender;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAge() {
        return age;
    }

    public void setAge(String age) {
        this.age = age;
    }

    public String getGender() {
        return gender;
    }
    
    public void setGender(String gender) {
        this.gender = gender;
    }
}

2.9.2 創建serivce下的UserInfoService.java

package com.liwl.servcie;

import java.util.List;

import com.liwl.model.UserInfo;

public interface UserInfoSerivce {
    void insertUserInfo(UserInfo userInfo);
    void deleteUserInfo(Long id);
    void updateUserInfo(Long id,UserInfo newUserInfo);
    List<UserInfo> getUserInfoList();
}

2.9.3 創建impl下的UserInfoServiceImpl.java

package com.liwl.servcie.impl;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Service;
import com.liwl.model.UserInfo;
import com.liwl.servcie.UserInfoSerivce;

@Service
public class UserInfoServiceImpl implements UserInfoSerivce {

    @Autowired
    JdbcTemplate jdbcTemplate;

    @Override
    public void insertUserInfo(UserInfo userInfo) {
        jdbcTemplate.execute("insert into t_user_info(name,age,gender) values('"+userInfo.getName()+"+"+userInfo.getAge()+"+"+userInfo.getGender()+"')");
    }

    @Override
    public void deleteUserInfo(Long id) {
        jdbcTemplate.execute("delete from t_user_info where id="+id);
    }

    @Override
    public void updateUserInfo(Long id, UserInfo newUserInfo) {
        jdbcTemplate.update("update t_user_info set name=?,age=?,gender=? where id=?",new Object[]{
            new UserInfo().getName(),
            new UserInfo().getAge(),
            new UserInfo().getGender(),
        });
    }

    @Override
    public List<UserInfo> getUserInfoList() {
        List<UserInfo> userInfos = new ArrayList<>();
        List<Map<String,Object>> results = jdbcTemplate.queryForList("select * from t_user_info");
        for (Map<String,Object> obj: results){
            UserInfo userInfo = new UserInfo();
            userInfo.setId((Long) obj.get("id"));
            userInfo.setName((String) obj.get("name"));
            userInfo.setAge((String) obj.get("age"));
            userInfo.setGender((String) obj.get("gender"));
            userInfos.add(userInfo);
        }
        return userInfos;
    }    
}

2.9.4創建controller下的GetUserInfoController.java

package com.liwl.controller;

import java.util.List;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

import com.liwl.model.UserInfo;
import com.liwl.servcie.UserInfoSerivce;

@Controller
public class GetUserInfoController {

    @Autowired
    UserInfoSerivce userInfoSerivce;
    
    @RequestMapping("/getUserInfo")
    public ModelAndView getUserInfo(HttpServletRequest httpServletRequest,HttpServletResponse httpServletResponse) throws Exception{
        ModelAndView modelAndView = new ModelAndView();
        List<UserInfo> userInfoList = userInfoSerivce.getUserInfoList();
        modelAndView.addObject("data",userInfoList);
        modelAndView.setViewName("success");
        return modelAndView;
    }
}

2.9.5 創建WEB-INF/views下的success.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<html>
<body>
<h2>跳轉到success了!!!</h2>
<p>
    <c:forEach items="${data}" var="d">
        <tr><td>${d.id}</td></tr>
        <tr><td>${d.name}</td></tr>
        <tr><td>${d.age}</td></tr>
        <tr><td>${d.gender}</td></tr>
        </br>
    </c:forEach>
</p>
</body>
</html>

2.9.6 修改pom.xml

因爲success.jsp使用了<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>，所以pom.xml裏面添加

<!-- jstl 標籤庫  -->
<dependency>  
  <groupId>javax.servlet</groupId>  
  <artifactId>jstl</artifactId>  
  <version>1.2</version>  
  <scope>runtime</scope>  
</dependency>  
<!-- jsp 標準標籤庫 -->
<dependency>
<groupId>taglibs</groupId>
<artifactId>standard</artifactId>
<version>1.1.2</version>
</dependency>

2.9.7 修改web.xml

這裏jdbcTemplate的bean注入，還是採用xml方式。所以增加web.xml的內容：

<?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-3.0.xsd 
       http://www.springframework.org/schema/mvc 
       http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd 
       http://www.springframework.org/schema/context 
       http://www.springframework.org/schema/context/spring-context.xsd"
       default-lazy-init="true">

    <!-- 處理器映射器，將處理器Handler的name作爲URL進行查找 -->
    <bean class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"></bean>

    <!-- 處理器適配器，適配處理器中handlerRequest方法的調用 -->
    <bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter"></bean>

    <!-- 配置視圖解析器，把handler方法返回的邏輯視圖解析爲實際的物理視圖 -->
    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/views/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

    <!-- Spring內置連接池 -->
    <bean id="driverManagerDataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/liwldev_java_web_springmvc"></property>
        <property name="username" value="liwl"></property>
        <property name="password" value="liwanliang"></property>
    </bean>

    <!--指定連接池-->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
            <property name="dataSource" ref="driverManagerDataSource"></property>
    </bean>

    <mvc:annotation-driven></mvc:annotation-driven>
    <context:component-scan base-package="com.liwl"></context:component-scan>
</beans>

2.10 運行測試

略