freemarker.cache.MergingTemplateConfigurationFactory Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 freemarker.cache;
import java.io.IOException;
import freemarker.core.TemplateConfiguration;
import freemarker.template.Configuration;
/**
* Returns the merged results of all the child factories. The factories are merged in the order as they were added.
* {@code null} results from the child factories will be ignored. If all child factories return {@code null}, the result
* of this factory will be {@code null} too.
*
* @since 2.3.24
*/
public class MergingTemplateConfigurationFactory extends TemplateConfigurationFactory {
private final TemplateConfigurationFactory[] templateConfigurationFactories;
public MergingTemplateConfigurationFactory(TemplateConfigurationFactory... templateConfigurationFactories) {
this.templateConfigurationFactories = templateConfigurationFactories;
}
@Override
public TemplateConfiguration get(String sourceName, Object templateSource)
throws IOException, TemplateConfigurationFactoryException {
TemplateConfiguration mergedTC = null;
TemplateConfiguration resultTC = null;
for (TemplateConfigurationFactory tcf : templateConfigurationFactories) {
TemplateConfiguration tc = tcf.get(sourceName, templateSource);
if (tc != null) {
if (resultTC == null) {
resultTC = tc;
} else {
if (mergedTC == null) {
Configuration cfg = getConfiguration();
if (cfg == null) {
throw new IllegalStateException(
"The TemplateConfigurationFactory wasn't associated to a Configuration yet.");
}
mergedTC = new TemplateConfiguration();
mergedTC.setParentConfiguration(cfg);
mergedTC.merge(resultTC);
resultTC = mergedTC;
}
mergedTC.merge(tc);
}
}
}
return resultTC;
}
@Override
protected void setConfigurationOfChildren(Configuration cfg) {
for (TemplateConfigurationFactory templateConfigurationFactory : templateConfigurationFactories) {
templateConfigurationFactory.setConfiguration(cfg);
}
}
}