freemarker + spring 配置和最简单的例子

Question

尽管有很多关于 freemarker + spring 的讨论，但是很难找到可以复制和运行.
的简洁的工作示例您能否在 spring xml 上下文中提供 freemarker 的最简单工作配置和 java 代码片段以从资源文件加载模板并进行处理。

Answer 1

最佳工作示例。您可以下载源代码 here.

Answer 2

pom.xml

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context-support</artifactId>
</dependency>
<dependency>
    <groupId>org.freemarker</groupId>
    <artifactId>freemarker</artifactId>
</dependency>

applicationContext.xml

<bean id="freeMarkerConfigurationFactory" class="org.springframework.ui.freemarker.FreeMarkerConfigurationFactoryBean">
    <property name="templateLoaderPath" value="classpath:/META-INF/freemarker"/>
    <property name="preferFileSystemAccess" value="false"/>
</bean>

AlertMailComposer.java

import static org.springframework.ui.freemarker.FreeMarkerTemplateUtils.processTemplateIntoString;

@Component
public class AlertMailComposer implements Processor {
    
    public static final String TEMPLATE = "AlertMail.ftl";
    
    @Autowired
    private Configuration freemarkerConfiguration;
    
    protected String composeHtml(Alert alert) throws IOException, TemplateException {
        return processTemplateIntoString(freemarkerConfiguration.getTemplate(TEMPLATE), ImmutableMap.of(
                "alertType", alert.getAlertType(),
                "message", alert.getMessage(),
                "nodeName", alert.getEvent().getNodeName(),
                "event", toJson(alert.getEvent(), true)
        ));
    }
...

AlertMail.ftl

<html>
<body style="font-family:verdana;font-size:10">
    <b>${alertType}: </b>${message}<br>
    <b>on: </b>${nodeName}<br>
    <p/>
    <pre style="font-family:verdana;font-size:10;color:grey">
${event}
    </pre>
</body>
</html>

Configuration class 有一些有趣的属性，比如 ClassForTemplateLoading 加载相对于某些 class 的资源或使用 basePackagePath。类似于 Class.getResource.

@Autowired
private FreeMarkerConfigurationFactory freeMarkerConfigurationFactory;

@Bean
public freemarker.template.Configuration negativeRatesFreeMarkerConfiguration() throws IOException, TemplateException {
    freemarker.template.Configuration configuration = freeMarkerConfigurationFactory.createConfiguration();
    configuration.setClassForTemplateLoading(getClass(), "/" + getClass().getPackage().getName().replace('.', '/'));
    return configuration;
}

...

@Resource(name = "negativeRatesFreeMarkerConfiguration")
private Configuration freemarkerConfiguration;

...

freemarkerConfiguration.getTemplate("/service/emailReport.ftl")

Answer 3

在 spring 上下文 xml 中，声明 FreemarkerConfigurationFactoryBean 就足够了，即

<bean id="freemarkerConfigFactory" class="org.springframework.ui.freemarker.FreeMarkerConfigurationFactoryBean">
    <property name="templateLoaderPath" value="classpath:templates/"/>
</bean>

如果使用@Autowired注释，则无需在xml文件中进一步指定freemarker.template.Configuration bean。它由工厂创建并由 Spring.

注入

Answer 4

除了 pom.xml 中的 maven 依赖项与 spring 中的 java 配置一起使用，您还可以 -

public class MyWebAppInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {

    @Override
    protected Class<?>[] getRootConfigClasses() {
        return new Class<?>[] { MyRootContextConfig.class };
    }

    @Override
    protected Class<?>[] getServletConfigClasses() {
        return new Class<?>[] { MyServletContextConfig.class };
    }

    @Override
    protected String[] getServletMappings() {
        return new String[] { "/test/*" };
    } 

}

然后MyRootContextConfig可以有

@Bean(name = "myFreeMarkerConfigruation")
public FreeMarkerConfigurationFactoryBean getFreeMarkerConfiguration() {
    FreeMarkerConfigurationFactoryBean bean = new FreeMarkerConfigurationFactoryBean();
    bean.setTemplateLoaderPath("classpath:/templates/");
    return bean;
}

freemarker + spring 配置和最简单的例子

freemarker + spring configuration and simplest example

java

spring

freemarker