PrestoHadoopConfiguration.java

/*
 * 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.presto.hive;

import com.google.common.collect.ClassToInstanceMap;
import com.google.common.collect.ImmutableClassToInstanceMap;
import org.apache.hadoop.conf.Configuration;

import static com.google.common.base.Preconditions.checkArgument;
import static java.util.Objects.requireNonNull;

public final class PrestoHadoopConfiguration
        extends Configuration
{
    private final ClassToInstanceMap<Object> services;

    public PrestoHadoopConfiguration(ClassToInstanceMap<?> services)
    {
        super(false);
        this.services = ImmutableClassToInstanceMap.copyOf(requireNonNull(services, "services is null"));
    }

    public <T> T getService(Class<T> type)
    {
        T service = services.getInstance(type);
        checkArgument(service != null, "service not found: %s", type.getName());
        return service;
    }
}