HttpComponents Client Source Code Files

HttpComponents Client Source Code Files are provided in the source package file,

You can download as described in the previous tutorial and go to the "httpclient5/src" sub-folder to view Source Code files.

You can also browse HttpComponents Client Source Code below:



 * ====================================================================
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF 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
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * ====================================================================
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <>.
package org.apache.hc.client5.http.impl;

import java.util.Arrays;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

import org.apache.hc.client5.http.DnsResolver;
import org.apache.hc.core5.annotation.Contract;
import org.apache.hc.core5.annotation.ThreadingBehavior;
import org.apache.hc.core5.util.Args;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

 * In-memory {@link DnsResolver} implementation.
 * @since 4.2
@Contract(threading = ThreadingBehavior.STATELESS)
public class InMemoryDnsResolver implements DnsResolver {

    /** Logger associated to this class. */
    private static final Logger LOG = LoggerFactory.getLogger(InMemoryDnsResolver.class);

     * In-memory collection that will hold the associations between a host name
     * and an array of InetAddress instances.
    private final Map<String, InetAddress[]> dnsMap;

     * Builds a DNS resolver that will resolve the host names against a
     * collection held in-memory.
    public InMemoryDnsResolver() {
        dnsMap = new ConcurrentHashMap<>();

     * Associates the given array of IP addresses to the given host in this DNS overrider.
     * The IP addresses are assumed to be already resolved.
     * @param host
     *            The host name to be associated with the given IP.
     * @param ips
     *            array of IP addresses to be resolved by this DNS overrider to the given
     *            host name.
    public void add(final String host, final InetAddress... ips) {
        Args.notNull(host, "Host name");
        Args.notNull(ips, "Array of IP addresses");
        dnsMap.put(host, ips);

     * {@inheritDoc}
    public InetAddress[] resolve(final String host) throws UnknownHostException {
        final InetAddress[] resolvedAddresses = dnsMap.get(host);
        if (LOG.isInfoEnabled()) {
  "Resolving {} to {}", host, Arrays.deepToString(resolvedAddresses));
        if(resolvedAddresses == null){
            throw new UnknownHostException(host + " cannot be resolved");
        return resolvedAddresses;

    public String resolveCanonicalHostname(final String host) throws UnknownHostException {
        final InetAddress[] resolvedAddresses = resolve(host);
        if (resolvedAddresses.length > 0) {
            return resolvedAddresses[0].getCanonicalHostName();
        return host;


Or download all them as a single archive file:

File name:
File size: 625318 bytes
Release date: 2022-11-10


Download and Install HttpComponents Core Binary Package

Download and Install HttpComponents Client Source Package

Download and Review Apache HttpComponents-*.jar

⇑⇑ FAQ for Apache HttpComponents JAR Library

2023-03-26, 9769👍, 1💬