ratpack.registry.internal.HierarchicalRegistry.java Source code

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Here is the source code for ratpack.registry.internal.HierarchicalRegistry.java

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/*
 * Copyright 2013 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 ratpack.registry.internal;

import com.google.common.collect.Iterables;
import com.google.common.reflect.TypeToken;
import ratpack.func.Function;
import ratpack.registry.Registry;

import java.util.Optional;

public class HierarchicalRegistry implements Registry {

    private final Registry parent;
    private final Registry child;

    public HierarchicalRegistry(Registry parent, Registry child) {
        this.parent = parent;
        this.child = child;
    }

    @Override
    public <O> Optional<O> maybeGet(TypeToken<O> type) {
        Optional<O> object = child.maybeGet(type);
        if (!object.isPresent()) {
            object = parent.maybeGet(type);
        }

        return object;
    }

    @Override
    public <O> Iterable<? extends O> getAll(TypeToken<O> type) {
        Iterable<? extends O> childAll = child.getAll(type);
        Iterable<? extends O> parentAll = parent.getAll(type);
        return Iterables.concat(childAll, parentAll);
    }

    @Override
    public <T, O> Optional<O> first(TypeToken<T> type, Function<? super T, ? extends O> function) throws Exception {
        Optional<O> first = child.first(type, function);
        if (!first.isPresent()) {
            first = parent.first(type, function);
        }
        return first;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }

        HierarchicalRegistry that = (HierarchicalRegistry) o;

        return child.equals(that.child) && parent.equals(that.parent);
    }

    @Override
    public int hashCode() {
        int result = parent.hashCode();
        result = 31 * result + child.hashCode();
        return result;
    }

    @Override
    public String toString() {
        return "HierarchicalRegistry{parent=" + parent + ", child=" + child + '}';
    }
}