Руководство Spring MVC и FreeMarker

Что такое FreeMarker?
Создать Maven Web App Project
Конфигурация web.xml & pom.xml
Конфигурация Spring MVC
Model, Form, Controller
FreeMarker Views
Запуск примера

1. Что такое FreeMarker?

FreeMarker это технология на уровне View. Используется для отображения данных. FreeMarker можно использовать для отображения данных вместо Jsp. FreeMarker на самом деле является текстовым документом.

FreeMarker engine

FreeMarker Engine комбинирует данные из уровня Model и шаблоны FreeMarker (FreeMarker template) чтобы создать данные HTML.

Смотреть пример:

See more:
Руководство Spring Boot и FreeMarker

2. Создать Maven Web App Project

Создайте пустой Maven Web App Project в Eclipse с названием "SpringMVCFreeMarker".

Создайте пустой проект Maven Web App в Eclipse

3. Конфигурация web.xml & pom.xml

Используем WebApp >= 3.

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<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_3_0.xsd"
    id="WebApp_ID" version="3.0">
   
    <display-name>SpringMVCFreeMarker</display-name>
   
</web-app>

Объявить использующиеся библиотеки

pom.xml

<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>org.o7planning</groupId>
  <artifactId>SpringMVCFreeMarker</artifactId>
  <packaging>war</packaging>
  <version>0.0.1-SNAPSHOT</version>
 
  <name>SpringMVCFreeMarker Maven Webapp</name>
  <url>http://maven.apache.org</url>
  <dependencies>
 
 
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
     
    </dependency>
   
        <!-- Servlet Library -->
        <!-- http://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>provided</scope>
        </dependency>
   
   
        <!-- Spring dependencies -->
        <!-- http://mvnrepository.com/artifact/org.springframework/spring-core -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>

        <!-- http://mvnrepository.com/artifact/org.springframework/spring-web -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>

        <!-- http://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework/spring-context-support -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>


        <!-- https://mvnrepository.com/artifact/org.freemarker/freemarker -->
        <dependency>
            <groupId>org.freemarker</groupId>
            <artifactId>freemarker</artifactId>
            <version>2.3.23</version>
        </dependency>


    </dependencies>
   

    <build>
        <finalName>SpringMVCFreeMarker</finalName>
        <plugins>
       
            <!-- Config: Maven Tomcat Plugin -->
            <!-- http://mvnrepository.com/artifact/org.apache.tomcat.maven/tomcat7-maven-plugin -->
            <plugin>
                <groupId>org.apache.tomcat.maven</groupId>
                <artifactId>tomcat7-maven-plugin</artifactId>
                <version>2.2</version>
                <!-- Config: contextPath and Port (Default: /SpringMVCFreeMarker : 8080) -->
                <!--
                <configuration>
                    <path>/</path>
                    <port>8899</port>
                </configuration>
                -->   
            </plugin>
        </plugins>
    </build>   
   
</project>

4. Конфигурация Spring MVC

SpringWebAppInitializer.java

package org.o7planning.springmvcfreemarker.config;

import javax.servlet.FilterRegistration;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;

import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.ContextLoaderListener;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.filter.CharacterEncodingFilter;
import org.springframework.web.servlet.DispatcherServlet;

public class SpringWebAppInitializer implements WebApplicationInitializer {

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        AnnotationConfigWebApplicationContext appContext = new AnnotationConfigWebApplicationContext();
        appContext.register(ApplicationContextConfig.class);

        // Dispatcher Servlet
        ServletRegistration.Dynamic dispatcher = servletContext.addServlet("SpringDispatcher",
                new DispatcherServlet(appContext));
        dispatcher.setLoadOnStartup(1);
        dispatcher.addMapping("/");

        
        dispatcher.setInitParameter("contextClass", appContext.getClass().getName());

        servletContext.addListener(new ContextLoaderListener(appContext));

        // UTF8 Charactor Filter.
        FilterRegistration.Dynamic fr = servletContext.addFilter("encodingFilter", CharacterEncodingFilter.class);

        fr.setInitParameter("encoding", "UTF-8");
        fr.setInitParameter("forceEncoding", "true");
        fr.addMappingForUrlPatterns(null, true, "/*");
    }

}

WebMvcConfig.java

package org.o7planning.springmvcfreemarker.config;

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;


@Configuration
@EnableWebMvc
public class WebMvcConfig extends WebMvcConfigurerAdapter {

 
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
         // Default.
    }

     
    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
    }
 
}

В классе ApplicationContextConfig вм нужно объявить 2 Spring Bean - viewResolver & freemarkerConfig.

ApplicationContextConfig.java

package org.o7planning.springmvcfreemarker.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer;
import org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver;

@Configuration

@ComponentScan("org.o7planning.springmvcfreemarker.*")

public class ApplicationContextConfig {

    @Bean(name = "viewResolver")
    public ViewResolver getViewResolver() {
        FreeMarkerViewResolver viewResolver = new FreeMarkerViewResolver();
        System.out.println("Create Bean viewResolver");

        viewResolver.setCache(true);
        viewResolver.setPrefix("");
        viewResolver.setSuffix(".ftl");
        return viewResolver;
    }

    @Bean(name = "freemarkerConfig")
    public FreeMarkerConfigurer getFreemarkerConfig() {
        FreeMarkerConfigurer config = new FreeMarkerConfigurer();

        // Folder containing FreeMarker templates.
        config.setTemplateLoaderPath("/WEB-INF/views/");
        return config;
    }

}

5. Model, Form, Controller

Person.java

package org.o7planning.springmvcfreemarker.model;

public class Person {

    private String firstName;
    private String lastName;

    public Person() {
        
    }

    public Person(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

}

PersonForm.java

package org.o7planning.springmvcfreemarker.form;

public class PersonForm {

    private String firstName;
    private String lastName;

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
    
}

Controller:

MainController.java

package org.o7planning.springmvcfreemarker.controller;

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

import org.o7planning.springmvcfreemarker.form.PersonForm;
import org.o7planning.springmvcfreemarker.model.Person;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

@Controller
public class MainController {

    private static List<Person> persons = new ArrayList<Person>();

    static {
        persons.add(new Person("Bill", "Gates"));
        persons.add(new Person("Steve", "Jobs"));
    }

    @RequestMapping(value = { "/", "/index" }, method = RequestMethod.GET)
    public String index(Model model) {

        model.addAttribute("persons", persons);

        return "index";
    }

    @RequestMapping(value = { "/addPerson" }, method = RequestMethod.GET)
    public String addPersonForm(Model model) {

        PersonForm personForm = new PersonForm();
        model.addAttribute("personForm", personForm);

        return "addPerson";
    }

    @RequestMapping(value = { "/addPerson" }, method = RequestMethod.POST)
    public String addPersonSave(Model model, //
            @ModelAttribute("personForm") PersonForm personForm) {

        String firstName = personForm.getFirstName();
        String lastName = personForm.getLastName();

        if (firstName != null && firstName.length() > 0 //
                && lastName != null && lastName.length() > 0) {
            Person newPerson = new Person(firstName, lastName);
            persons.add(newPerson);

            return "redirect:/index";
        }
        String error = "First Name & Last Name is required!";
        model.addAttribute("errorMessage", error);
        return "addPerson";
    }

}

6. FreeMarker Views

/WEB-INF/views/index.ftl

<html>
   <head>
      <title>Person List</title>
   </head>  
   <body>
     <h3>Person List</h3>
     <a href="addPerson">Add Person</a>
     <br><br>
      <div>
        
         <table border="1">
            <tr>
               <th>First Name</th>
               <th>Last Name</th>
            </tr>
            <#list persons as person>
            <tr>
               <td>${person.firstName}</td>
               <td>${person.lastName}</td>
            </tr>
            </#list>
         </table>
      </div>
   </body>
</html>

/WEB-INF/views/addPerson.ftl

<!--
   freemarker macros have to be imported into a namespace.
   We strongly recommend sticking to 'spring'
   -->

<#import "/spring.ftl" as spring/>

<html>
   <head>
      <title>Add Person</title>
   </head>
   <body>
      <#if errorMessage??>
      <div style="color:red;font-style:italic;">
         ${errorMessage}
      </div>
      </#if>
     
      <div>
         <fieldset>
            <legend>Add Person</legend>
            <form name="person" action="" method="POST">
               First Name: <@spring.formInput "personForm.firstName" "" "text"/>    <br/>
               Last Name: <@spring.formInput "personForm.lastName" "" "text"/>    <br/>
               <input type="submit" value="Create" />
            </form>
         </fieldset>
      </div>
     
     
   </body>
  
</html>