Spring Boot 整合 FreeMarker Web 案例教程
SpringBoot 很方便的集成 FreeMarker ，DAO 数据库操作层依旧用的是 Mybatis，本文将会一步一步到来如何集成 FreeMarker 以及配置的详解：
二、运行 springboot-freemarker 工程
git clone 下载工程 springboot-learning-example ，项目地址见 GitHub https://github.com/JeffLi1993/springboot-learning-example
下面开始运行工程步骤（Quick Start）：
1.数据库准备
a.创建数据库 springbootdb：
CREATE DATABASE springbootdb;
b.创建表 city ：(因为我喜欢徒步)
DROP TABLE IF EXISTS `city`;
CREATE TABLE `city` (
`id` int(10) unsigned NOT NULL AUTO_INCREMENT COMMENT '城市编号',
`province_id` int(10) unsigned NOT NULL COMMENT '省份编号',
`city_name` varchar(25) DEFAULT NULL COMMENT '城市名称',
`description` varchar(25) DEFAULT NULL COMMENT '描述',
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO\_INCREMENT=1 DEFAULT CHARSET=utf8;
c.插入数据
INSERT city VALUES (1 ,1,'温岭市','BYSocket 的家在温岭。');
2. 项目结构介绍
项目结构如下图所示：
org.spring.springboot.controller - Controller 层
org.spring.springboot.dao - 数据操作层 DAO
org.spring.springboot.domain - 实体类
org.spring.springboot.service - 业务逻辑层
Application - 应用启动类
resources/application.properties - 应用配置文件，应用启动会自动读取配置
resources/web - *.ftl文件，是 FreeMarker 文件配置路径。在 application.properties 配置
resources/mapper - DAO Maper XML 文件
3.改数据库配置
打开 application.properties 文件， 修改相应的数据源配置，比如数据源地址、账号、密码等。（如果不是用 MySQL，pom 自行添加连接驱动依赖，然后修改驱动名配置。）
4.编译工程
在项目根目录 springboot-learning-example，运行 maven 指令：
mvn clean install
5.运行工程
右键运行 springboot-freemarker 工程 Application 应用启动类的 main 函数，然后在浏览器访问：
获取 ID 编号为 1 的城市信息页面：
localhost:8080/api/city/1
获取城市列表页面：
localhost:8080/api/city
6.补充
运行环境：JDK 7 或 8，Maven 3.0+
技术栈：SpringBoot、Mybatis、FreeMarker
三、 springboot-freemarker 工程配置详解
具体代码见 GitHub https://github.com/JeffLi1993/springboot-learning-example
1.pom.xml 依赖
pom.xml 代码如下：
<?xml version="1.0" encoding="UTF-8"?>
<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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>springboot</groupId>
<artifactId>springboot-freemarker</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>springboot-freemarker :: Spring Boot 集成 FreeMarker 案例</name>
<!-- Spring Boot 启动父依赖 -->
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.1.RELEASE</version>
</parent>
<properties>
<mybatis-spring-boot>1.2.0</mybatis-spring-boot>
<mysql-connector>5.1.39</mysql-connector>
</properties>
<dependencies>
<!-- Spring Boot Freemarker 依赖 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-freemarker</artifactId>
</dependency>
<!-- Spring Boot Web 依赖 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- Spring Boot Test 依赖 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!-- Spring Boot Mybatis 依赖 -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>${mybatis-spring-boot}</version>
</dependency>
<!-- MySQL 连接驱动依赖 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql-connector}</version>
</dependency>
<!-- Junit -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
</dependencies>
</project>
在 pom.xml 依赖中增加 Spring Boot FreeMarker 依赖。
###2.配置 FreeMarker
然后在 application.properties 中加入 FreeMarker 相关的配置：
## Freemarker 配置
## 文件配置路径
spring.freemarker.template-loader-path=classpath:/web/
spring.freemarker.cache=false
spring.freemarker.charset=UTF-8
spring.freemarker.check-template-location=true
spring.freemarker.content-type=text/html
spring.freemarker.expose-request-attributes=true
spring.freemarker.expose-session-attributes=true
spring.freemarker.request-context-attribute=request
spring.freemarker.suffix=.ftl
这是我这块的配置，如果需要更多的 FreeMarker 配置，可以查看下面的详解：
spring.freemarker.allow-request-override=false # Set whether HttpServletRequest attributes are allowed to override (hide) controller generated model attributes of the same name.
spring.freemarker.allow-session-override=false # Set whether HttpSession attributes are allowed to override (hide) controller generated model attributes of the same name.
spring.freemarker.cache=false # Enable template caching.
spring.freemarker.charset=UTF-8 # Template encoding.
spring.freemarker.check-template-location=true # Check that the templates location exists.
spring.freemarker.content-type=text/html # Content-Type value.
spring.freemarker.enabled=true # Enable MVC view resolution for this technology.
spring.freemarker.expose-request-attributes=false # Set whether all request attributes should be added to the model prior to merging with the template.
spring.freemarker.expose-session-attributes=false # Set whether all HttpSession attributes should be added to the model prior to merging with the template.
spring.freemarker.expose-spring-macro-helpers=true # Set whether to expose a RequestContext for use by Spring's macro library, under the name "springMacroRequestContext".
spring.freemarker.prefer-file-system-access=true # Prefer file system access for template loading. File system access enables hot detection of template changes.
spring.freemarker.prefix= # Prefix that gets prepended to view names when building a URL.
spring.freemarker.request-context-attribute= # Name of the RequestContext attribute for all views.
spring.freemarker.settings.\*= # Well-known FreeMarker keys which will be passed to FreeMarker's Configuration.
spring.freemarker.suffix= # Suffix that gets appended to view names when building a URL.
spring.freemarker.template-loader-path=classpath:/templates/ # Comma-separated list of template paths.
spring.freemarker.view-names= # White list of view names that can be resolved.
3.展示层 Controller 详解
/\*\*
\* 城市 Controller 实现 Restful HTTP 服务
\* <p>
\* Created by bysocket on 07/02/2017.
\*/
@Controller
public class CityController {
@Autowired
private CityService cityService;
@RequestMapping(value = "/api/city/{id}", method = RequestMethod.GET)
public String findOneCity(Model model, @PathVariable("id") Long id) {
model.addAttribute("city", cityService.findCityById(id));
return "city";
}
@RequestMapping(value = "/api/city", method = RequestMethod.GET)
public String findAllCity(Model model) {
List<City> cityList = cityService.findAllCity();
model.addAttribute("cityList",cityList);
return "cityList";
}
}
a.这里不是走 HTTP + JSON 模式，使用了 @Controller 而不是先前的 @RestController
b.方法返回值是 String 类型，和 application.properties 配置的 Freemarker 文件配置路径下的各个 *.ftl 文件名一致。这样才会准确地把数据渲染到 ftl 文件里面进行展示。
c.用 Model 类，向 Model 加入数据，并指定在该数据在 Freemarker 取值指定的名称。
四、小结
FreeMarker 是常用的模板引擎，很多开发 Web 的必选。
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