/*
* Copyright 2013-present Facebook, 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 com.facebook.buck.rules.keys;
import com.facebook.buck.rules.BuildRule;
import com.facebook.buck.rules.RuleKey;
import javax.annotation.Nullable;
public interface RuleKeyFactory<RULE_KEY> {
/**
* Creates a new {@code RULE_KEY} for the given {@link BuildRule}. In most cases {@code RULE_KEY}
* is going to be {@link RuleKey}, but it can be anything really.
*
* @param buildRule The build rule to create the key for.
* @return A rule key.
*/
RULE_KEY build(BuildRule buildRule);
/**
* Returns a {@code RULE_KEY} from an internal cache, if possible. If a non-null value is
* returned, it is guaranteed to be he same as if {@link #build} were called instead.
*/
@Nullable
@SuppressWarnings("unused")
default RULE_KEY getFromCache(BuildRule buildRule) {
return null;
}
}