/**
* Copyright 2012-2018 The Feign 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 feign;
import feign.codec.EncodeException;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* A QueryMapEncoder encodes Objects into maps of query parameter names to values.
*/
public interface QueryMapEncoder {
/**
* Encodes the given object into a query map.
*
* @param object the object to encode
* @return the map represented by the object
*/
Map encode(Object object);
class Default implements QueryMapEncoder {
private final Map, ObjectParamMetadata> classToMetadata =
new HashMap, ObjectParamMetadata>();
@Override
public Map encode(Object object) throws EncodeException {
try {
ObjectParamMetadata metadata = getMetadata(object.getClass());
Map fieldNameToValue = new HashMap();
for (Field field : metadata.objectFields) {
Object value = field.get(object);
if (value != null && value != object) {
fieldNameToValue.put(field.getName(), value);
}
}
return fieldNameToValue;
} catch (IllegalAccessException e) {
throw new EncodeException("Failure encoding object into query map", e);
}
}
private ObjectParamMetadata getMetadata(Class> objectType) {
ObjectParamMetadata metadata = classToMetadata.get(objectType);
if (metadata == null) {
metadata = ObjectParamMetadata.parseObjectType(objectType);
classToMetadata.put(objectType, metadata);
}
return metadata;
}
private static class ObjectParamMetadata {
private final List objectFields;
private ObjectParamMetadata(List objectFields) {
this.objectFields = Collections.unmodifiableList(objectFields);
}
private static ObjectParamMetadata parseObjectType(Class> type) {
List fields = new ArrayList();
for (Field field : type.getDeclaredFields()) {
if (!field.isAccessible()) {
field.setAccessible(true);
}
fields.add(field);
}
return new ObjectParamMetadata(fields);
}
}
}
}