io.mandrel.requests.dns.CachedNameResolver.java Source code

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Here is the source code for io.mandrel.requests.dns.CachedNameResolver.java

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/*
 * Licensed to Mandrel under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Mandrel licenses this file to you 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 io.mandrel.requests.dns;

import io.mandrel.common.service.TaskContext;

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.HashMap;
import java.util.Map;
import java.util.stream.Collectors;

import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.experimental.Accessors;
import lombok.extern.slf4j.Slf4j;

import org.apache.commons.lang3.tuple.Pair;

import com.fasterxml.jackson.annotation.JsonProperty;
import com.google.common.base.Throwables;
import com.google.common.net.InetAddresses;

@Data
@Slf4j
@Accessors(chain = true, fluent = true)
@EqualsAndHashCode(callSuper = false)
public class CachedNameResolver extends NameResolver {

    @Data
    @Accessors(chain = false, fluent = false)
    @EqualsAndHashCode(callSuper = false)
    public static class CachedNameResolverDefinition extends NameResolverDefinition<CachedNameResolver> {
        private static final long serialVersionUID = 4179034020754804054L;

        @JsonProperty("addresses")
        private Map<String, String> addresses = new HashMap<>();

        @Override
        public CachedNameResolver build(TaskContext context) {
            return new CachedNameResolver(context).addresses(addresses.entrySet().stream()
                    .map(entry -> Pair.of(entry.getKey(), InetAddresses.forString(entry.getValue())))
                    .collect(Collectors.toMap(p -> p.getLeft(), p -> p.getRight())));
        }

        @Override
        public String name() {
            return "cached";
        }
    }

    public CachedNameResolver(TaskContext context) {
        super(context);
    }

    private Map<String, InetAddress> addresses;

    public InetAddress resolve(String name) throws UnknownHostException {
        return name != null ? addresses.computeIfAbsent(name, key -> {
            try {
                return InetAddress.getByName(key);
            } catch (UnknownHostException e) {
                log.debug("", e);
                throw Throwables.propagate(e);
            }
        }) : null;
    }

    public void init() {
    }
}