step 1. 增加freemarker依赖

修改 pom.xml
在 <dependencies>标签内部追加以下配置

<?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/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
 
 ...

    <dependencies>
        ... 
        <dependency>
            <groupId>fr.ippon.spark.metrics</groupId>
            <artifactId>metrics-spark-reporter</artifactId>
            <version>${metrics-spark-reporter.version}</version>
        </dependency>
        <!-- jhipster-needle-maven-add-dependency -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-freemarker</artifactId>
        </dependency>
    </dependencies>
   ...
</project>

step 2. 修改application.yml配置

加完依赖的jar之后，我们还希望在freemarker模版中使用一些内置变量，则需要修改 src\main\resources\config\application.yml

# ===================================================================
# Spring Boot configuration.
#
# This configuration will be overriden by the Spring profile you use,
# for example application-dev.yml if you use the "dev" profile.
# ===================================================================

# ===================================================================
# Standard Spring Boot properties.
# Full reference is available at:
# http://docs.spring.io/spring-boot/docs/current/reference/html/common-application-properties.html
# ===================================================================

management:
    context-path: /management
    health:
        mail:
            enabled: false # When using the MailService, configure an SMTP server and set this to true
spring:
    application:
        name: cms
    .......
    thymeleaf:
        mode: XHTML
    freemarker:
        exposeSpringMacroHelpers: true
        exposeRequestAttributes: true
        exposeSessionAttributes: true
        requestContextAttribute: request
        contentType: text/html

.....

step 3. 添加自定义模版宏

创建一个新的java类

package cn.ctodb.cms.config;

import javax.annotation.PostConstruct;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;

import cn.ctodb.cms.freemarker.macro.CmsMyDirective;
import freemarker.template.Configuration;
import freemarker.template.DefaultObjectWrapperBuilder;
import freemarker.template.ObjectWrapper;
import freemarker.template.Version;

@org.springframework.context.annotation.Configuration
public class FreemarkerConfiguration {

    @Autowired
    protected Configuration           configuration;
    @Autowired
    protected CmsMyDirective          cms_my;

    @PostConstruct
    public void setSharedVariable() {
        configuration.setSharedVariable("cms_my", cms_my);
    }

}

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