google-nomulus/javatests/google/registry/testing/ReflectiveFieldExtractor.java
Justine Tunney 5012893c1d mv com/google/domain/registry google/registry
This change renames directories in preparation for the great package
rename. The repository is now in a broken state because the code
itself hasn't been updated. However this should ensure that git
correctly preserves history for each file.
2016-05-13 18:55:08 -04:00

37 lines
1.4 KiB
Java

// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
//
// 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 com.google.domain.registry.testing;
import static com.google.common.base.Preconditions.checkArgument;
import java.lang.reflect.Field;
/** Utility class for extracting encapsulated contents of objects for testing. */
public final class ReflectiveFieldExtractor {
/** Extracts private {@code fieldName} on {@code object} without public getter. */
public static <T> T extractField(Class<T> returnType, Object object, String fieldName)
throws NoSuchFieldException, SecurityException, IllegalAccessException {
Field field = object.getClass().getDeclaredField(fieldName);
field.setAccessible(true);
Object value = field.get(object);
checkArgument(value == null || returnType.isInstance(value));
@SuppressWarnings("unchecked")
T result = (T) value;
return result;
}
private ReflectiveFieldExtractor() {}
}