/*
* Copyright 2012-2014 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.boot.bind;
import java.beans.IntrospectionException;
import java.util.HashMap;
import java.util.Map;
import org.yaml.snakeyaml.constructor.Constructor;
import org.yaml.snakeyaml.introspector.Property;
import org.yaml.snakeyaml.introspector.PropertyUtils;
import org.yaml.snakeyaml.nodes.NodeId;
/**
* Extended version of snakeyaml's Constructor class to facilitate mapping custom YAML
* keys to Javabean property names.
*
* @author Luke Taylor
*/
public class YamlJavaBeanPropertyConstructor extends Constructor {
private final Map<Class<?>, Map<String, Property>> properties = new HashMap<Class<?>, Map<String, Property>>();
private final PropertyUtils propertyUtils = new PropertyUtils();
public YamlJavaBeanPropertyConstructor(Class<?> theRoot) {
super(theRoot);
this.yamlClassConstructors.put(NodeId.mapping,
new CustomPropertyConstructMapping());
}
public YamlJavaBeanPropertyConstructor(Class<?> theRoot,
Map<Class<?>, Map<String, String>> propertyAliases) {
this(theRoot);
for (Class<?> key : propertyAliases.keySet()) {
Map<String, String> map = propertyAliases.get(key);
if (map != null) {
for (String alias : map.keySet()) {
addPropertyAlias(alias, key, map.get(alias));
}
}
}
}
/**
* Adds an alias for a Javabean property name on a particular type. The values of YAML
* keys with the alias name will be mapped to the Javabean property.
* @param alias the alias to map
* @param type the type of property
* @param name the property name
*/
protected final void addPropertyAlias(String alias, Class<?> type, String name) {
Map<String, Property> typeMap = this.properties.get(type);
if (typeMap == null) {
typeMap = new HashMap<String, Property>();
this.properties.put(type, typeMap);
}
try {
typeMap.put(alias, this.propertyUtils.getProperty(type, name));
}
catch (IntrospectionException ex) {
throw new RuntimeException(ex);
}
}
class CustomPropertyConstructMapping extends ConstructMapping {
@Override
protected Property getProperty(Class<?> type, String name)
throws IntrospectionException {
Map<String, Property> forType = YamlJavaBeanPropertyConstructor.this.properties
.get(type);
Property property = (forType == null ? null : forType.get(name));
return (property == null ? super.getProperty(type, name) : property);
}
}
}