Spring FreeMarker
last modified October 18, 2023
Spring FreeMarker tutorial shows how to use FreeMarker template engine in a classic Spring application.
Spring is a popular Java application framework for creating enterprise applications.
FreeMarker
FreeMarker is a server-side Java template engine for both web and
standalone environments. Templates are written in the FreeMarker Template
Language (FTL), which is a simple, specialized language. FreeMarker templates
have .ftlh extension.
Spring FreeMarker example
The following application uses FreeMarker to generate views.
pom.xml
src
├───main
│ ├───java
│ │ └───com
│ │ └───zetcode
│ │ ├───config
│ │ │ MyWebInitializer.java
│ │ │ WebConfig.java
│ │ ├───controller
│ │ │ MyController.java
│ │ └───service
│ │ WordService.java
│ └───resources
│ │ logback.xml
│ └───templates
│ index.ftlh
│ showWords.ftlh
└───test
└───java
This is the project structure.
<?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>com.zetcode</groupId>
<artifactId>springfreemarkerex</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>war</packaging>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>17</maven.compiler.source>
<maven.compiler.target>17</maven.compiler.target>
<spring-version>5.3.23</spring-version>
</properties>
<dependencies>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.4.0</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring-version}</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>4.0.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring-version}</version>
</dependency>
<dependency>
<groupId>org.freemarker</groupId>
<artifactId>freemarker</artifactId>
<version>2.3.31</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>3.3.2</version>
</plugin>
<plugin>
<groupId>org.eclipse.jetty</groupId>
<artifactId>jetty-maven-plugin</artifactId>
<version>9.4.49.v20220914</version>
</plugin>
</plugins>
</build>
</project>
In the pom.xml we have the necessary dependencies.
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<logger name="org.springframework" level="ERROR"/>
<logger name="com.zetcode" level="INFO"/>
<appender name="consoleAppender" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<Pattern>%d{HH:mm:ss.SSS} %blue(%-5level) %magenta(%logger{36}) - %msg %n
</Pattern>
</encoder>
</appender>
<root>
<level value="INFO" />
<appender-ref ref="consoleAppender" />
</root>
</configuration>
The logback.xml is a configuration file for the Logback logging
library.
package com.zetcode.config;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
@Configuration
public class MyWebInitializer extends
AbstractAnnotationConfigDispatcherServletInitializer {
@Override
protected Class<?>[] getRootConfigClasses() {
return null;
}
@Override
protected Class<?>[] getServletConfigClasses() {
return new Class[]{WebConfig.class};
}
@Override
protected String[] getServletMappings() {
return new String[]{"/"};
}
}
MyWebInitializer registers the Spring
DispatcherServlet, which is a front controller for a Spring web
application.
@Override
protected Class<?>[] getServletConfigClasses() {
return new Class[]{WebConfig.class};
}
The getServletConfigClasses returns a web configuration class.
package com.zetcode.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer;
import org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver;
@Configuration
@EnableWebMvc
@ComponentScan(basePackages = {"com.zetcode"})
public class WebConfig implements WebMvcConfigurer {
@Bean
public FreeMarkerViewResolver freemarkerViewResolver() {
var resolver = new FreeMarkerViewResolver();
resolver.setCache(true);
resolver.setSuffix(".ftlh");
return resolver;
}
@Bean
public FreeMarkerConfigurer freemarkerConfig() {
var freeMarkerConfigurer = new FreeMarkerConfigurer();
freeMarkerConfigurer.setTemplateLoaderPath("classpath:/templates/");
return freeMarkerConfigurer;
}
}
WebConfig configures FreeMarker template engine. We set the
template files location to templates directory on the classpath.
(The resources is on the classpath.)
package com.zetcode.service;
import org.springframework.stereotype.Service;
import java.util.List;
@Service
public class WordService {
private final List<String> words = List.of("pen", "sky",
"rock", "forest", "falcon", "eagle");
public List<String> all() {
return words;
}
}
The WordService returns a few words.
package com.zetcode.controller;
import com.zetcode.service.WordService;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
@Controller
public class MyController {
@GetMapping(value = "/")
public String home() {
return "index";
}
@GetMapping(value = "/words")
public String showWords(Model model, WordService wordService) {
var words = wordService.all();
model.addAttribute("words", words);
return "showWords";
}
}
MyController provides mappings between request paths and handler
methods. We have two mappings: the home page and the
showWords page.
var words = wordService.all();
model.addAttribute("words", words);
We retrieve all the words using the wordService and put it into the
model. The model is passed to FreeMarker which will process the data in the
template.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Home page</title>
</head>
<body>
<p>
<a href="words">Show words</a>
</p>
</body>
</html>
The home page contains the anchor which shows all words.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Show words</title>
</head>
<body>
<h2>List of words</h2>
<ul>
<#list words as word>
<li>${word}</li>
</#list>
</ul>
</body>
</html>
With the FreeMarker's list directive, we show all the words in an
HTML list.
$ mvn jetty:run
We run the server and locate to localhost:8080 to get the home page,
which has the anchor.
In this article we have worked with the FreeMarker template
engine in a classic Spring application.
Author
List all Spring tutorials.