org.springframework.web.servlet.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
*
* https://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.servlet.view.freemarker;
import java.io.IOException;
import java.util.List;
import javax.servlet.ServletContext;
import freemarker.cache.ClassTemplateLoader;
import freemarker.cache.TemplateLoader;
import freemarker.ext.jsp.TaglibFactory;
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;
import org.springframework.web.context.ServletContextAware;
/**
* JavaBean to configure 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";
* you do not need any further configuration then.
*
*
* <bean id="freemarkerConfig" class="org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer">
* <property name="templateLoaderPath"><value>/WEB-INF/freemarker/</value></property>
* </bean>
*
* This bean must be included in the application context of any application
* using Spring's FreeMarkerView for web MVC. It exists purely to configure FreeMarker.
* It is not meant to be referenced by application components but just internally
* by FreeMarkerView. Implements FreeMarkerConfig to be found by FreeMarkerView without
* depending on the bean name of the configurer. Each DispatcherServlet can define its
* own FreeMarkerConfigurer if desired.
*
* Note that you can also refer to a preconfigured FreeMarker Configuration
* instance, for example one set up by FreeMarkerConfigurationFactoryBean, via
* the "configuration" property. This allows to share a FreeMarker Configuration
* for web and email usage, for example.
*
*
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 Darren Davison
* @author Rob Harrop
* @since 03.03.2004
* @see #setConfigLocation
* @see #setFreemarkerSettings
* @see #setTemplateLoaderPath
* @see #setConfiguration
* @see org.springframework.ui.freemarker.FreeMarkerConfigurationFactoryBean
* @see FreeMarkerView
*/
public class FreeMarkerConfigurer extends FreeMarkerConfigurationFactory
implements FreeMarkerConfig, InitializingBean, ResourceLoaderAware, ServletContextAware {
@Nullable
private Configuration configuration;
@Nullable
private TaglibFactory taglibFactory;
/**
* Set a preconfigured Configuration to use for the FreeMarker web config, e.g. a
* shared one for web and email usage, set up via FreeMarkerConfigurationFactoryBean.
* If this is not set, FreeMarkerConfigurationFactory's properties (inherited by
* this class) have to be specified.
* @see org.springframework.ui.freemarker.FreeMarkerConfigurationFactoryBean
*/
public void setConfiguration(Configuration configuration) {
this.configuration = configuration;
}
/**
* Initialize the {@link TaglibFactory} for the given ServletContext.
*/
@Override
public void setServletContext(ServletContext servletContext) {
this.taglibFactory = new TaglibFactory(servletContext);
}
/**
* Initialize FreeMarkerConfigurationFactory's Configuration
* if not overridden by a preconfigured 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;
}
/**
* Return the TaglibFactory object wrapped by this bean.
*/
@Override
public TaglibFactory getTaglibFactory() {
Assert.state(this.taglibFactory != null, "No TaglibFactory available");
return this.taglibFactory;
}
}