org.springframework.web.reactive.result.view.freemarker.FreeMarkerConfigurer Maven / Gradle / Ivy
/*
* Copyright 2002-2018 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.web.reactive.result.view.freemarker;
import java.io.IOException;
import java.util.List;
import freemarker.cache.ClassTemplateLoader;
import freemarker.cache.TemplateLoader;
import freemarker.template.Configuration;
import freemarker.template.TemplateException;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.context.ResourceLoaderAware;
import org.springframework.lang.Nullable;
import org.springframework.ui.freemarker.FreeMarkerConfigurationFactory;
import org.springframework.util.Assert;
/**
* Configures FreeMarker for web usage via the "configLocation" and/or
* "freemarkerSettings" and/or "templateLoaderPath" properties.
* The simplest way to use this class is to specify just a "templateLoaderPath"
* (e.g. "classpath:templates"); you do not need any further configuration then.
*
* This bean must be included in the application context of any application
* using {@link FreeMarkerView}. It exists purely to configure FreeMarker.
* It is not meant to be referenced by application components but just internally
* by {@code FreeMarkerView}. Implements {@link FreeMarkerConfig} to be found by
* {@code FreeMarkerView} without depending on the bean name the configurer.
*
*
Note that you can also refer to a pre-configured FreeMarker Configuration
* instance via the "configuration" property. This allows to share a FreeMarker
* Configuration for web and email usage for example.
*
*
TODO: macros
*
*
This configurer registers a template loader for this package, allowing to
* reference the "spring.ftl" macro library contained in this package:
*
*
* <#import "/spring.ftl" as spring/>
* <@spring.bind "person.age"/>
* age is ${spring.status.value}
*
* Note: Spring's FreeMarker support requires FreeMarker 2.3 or higher.
*
* @author Rossen Stoyanchev
* @since 5.0
*/
public class FreeMarkerConfigurer extends FreeMarkerConfigurationFactory
implements FreeMarkerConfig, InitializingBean, ResourceLoaderAware {
@Nullable
private Configuration configuration;
public FreeMarkerConfigurer() {
setDefaultEncoding("UTF-8");
}
/**
* Set a pre-configured Configuration to use for the FreeMarker web config,
* e.g. a shared one for web and email usage. If this is not set,
* FreeMarkerConfigurationFactory's properties (inherited by this class)
* have to be specified.
*/
public void setConfiguration(Configuration configuration) {
this.configuration = configuration;
}
/**
* Initialize FreeMarkerConfigurationFactory's Configuration
* if not overridden by a pre-configured FreeMarker Configuration.
* Sets up a ClassTemplateLoader to use for loading Spring macros.
* @see #createConfiguration
* @see #setConfiguration
*/
@Override
public void afterPropertiesSet() throws IOException, TemplateException {
if (this.configuration == null) {
this.configuration = createConfiguration();
}
}
/**
* This implementation registers an additional ClassTemplateLoader
* for the Spring-provided macros, added to the end of the list.
*/
@Override
protected void postProcessTemplateLoaders(List templateLoaders) {
templateLoaders.add(new ClassTemplateLoader(FreeMarkerConfigurer.class, ""));
}
/**
* Return the Configuration object wrapped by this bean.
*/
@Override
public Configuration getConfiguration() {
Assert.state(this.configuration != null, "No Configuration available");
return this.configuration;
}
}