/*
* Copyright © 2014-2016 Cask Data, Inc.
*
* 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 co.cask.cdap.internal.lang;
import co.cask.cdap.internal.guava.reflect.TypeToken;
import java.lang.reflect.Field;
import java.lang.reflect.Type;
/**
*
*/
public final class Fields {
/**
* Find a {@link Field} in the class hierarchy of the given type.
* @param classType The leaf class to start with.
* @param fieldName Name of the field.
* @return A {@link Field} if found.
* @throws NoSuchFieldException If the field is not found.
*/
public static Field findField(Type classType, String fieldName) throws NoSuchFieldException {
for (Class<?> clz : TypeToken.of(classType).getTypes().classes().rawTypes()) {
try {
return clz.getDeclaredField(fieldName);
} catch (NoSuchFieldException e) {
// OK to ignore, keep finding.
}
}
throw new NoSuchFieldException("Field " + fieldName + " not exists in the class hierarchy of " + classType);
}
private Fields() {}
}