集册 Java实例教程 定制和配置HTTP请求执行和连接管理的最常见方面apachehttp客户端

定制和配置HTTP请求执行和连接管理的最常见方面apachehttp客户端

欢马劈雪     最近更新时间:2020-01-02 10:19:05

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自定义和配置HTTP请求执行和连接管理的最常见方面apache http客户端

/*

 * --------------------------------------------------------------------

 * 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

 *

 *   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.

 * --------------------------------------------------------------------

 *

 * 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

 * <http://www.apache.org/>.

 *

 */

 /*
  from N o w  J a v a  .   c o m 
 */

package org.apache.http.examples.client;


import java.net.InetAddress;

import java.net.UnknownHostException;

import java.nio.charset.CodingErrorAction;

import java.util.Arrays;


import javax.net.ssl.SSLContext;


import org.apache.http.Consts;

import org.apache.http.Header;

import org.apache.http.HttpEntity;

import org.apache.http.HttpHost;

import org.apache.http.HttpRequest;

import org.apache.http.HttpResponse;

import org.apache.http.ParseException;

import org.apache.http.client.CookieStore;

import org.apache.http.client.CredentialsProvider;

import org.apache.http.client.config.AuthSchemes;/* from N o w J a v a . c o m - 时  代  Java*/

import org.apache.http.client.config.CookieSpecs;

import org.apache.http.client.config.RequestConfig;

import org.apache.http.client.methods.CloseableHttpResponse;

import org.apache.http.client.methods.HttpGet;

import org.apache.http.client.protocol.HttpClientContext;

import org.apache.http.config.ConnectionConfig;

import org.apache.http.config.MessageConstraints;

import org.apache.http.config.Registry;

import org.apache.http.config.RegistryBuilder;

import org.apache.http.config.SocketConfig;

import org.apache.http.conn.DnsResolver;

import org.apache.http.conn.HttpConnectionFactory;

import org.apache.http.conn.ManagedHttpClientConnection;

import org.apache.http.conn.routing.HttpRoute;

import org.apache.http.conn.socket.ConnectionSocketFactory;

import org.apache.http.conn.socket.PlainConnectionSocketFactory;

import org.apache.http.conn.ssl.SSLConnectionSocketFactory;

import org.apache.http.impl.DefaultHttpResponseFactory;

import org.apache.http.impl.client.BasicCookieStore;

import org.apache.http.impl.client.BasicCredentialsProvider;

import org.apache.http.impl.client.CloseableHttpClient;

import org.apache.http.impl.client.HttpClients;

import org.apache.http.impl.conn.DefaultHttpResponseParser;

import org.apache.http.impl.conn.DefaultHttpResponseParserFactory;

import org.apache.http.impl.conn.ManagedHttpClientConnectionFactory;

import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;

import org.apache.http.impl.conn.SystemDefaultDnsResolver;

import org.apache.http.impl.io.DefaultHttpRequestWriterFactory;

import org.apache.http.io.HttpMessageParser;

import org.apache.http.io.HttpMessageParserFactory;

import org.apache.http.io.HttpMessageWriterFactory;

import org.apache.http.io.SessionInputBuffer;

import org.apache.http.message.BasicHeader;

import org.apache.http.message.BasicLineParser;

import org.apache.http.message.LineParser;

import org.apache.http.ssl.SSLContexts;

import org.apache.http.util.CharArrayBuffer;


/**

 * This example demonstrates how to customize and configure the most common aspects

 * of HTTP request execution and connection management.

 */

public class ClientConfiguration {


    public final static void main(String[] args) throws Exception {


        // Use custom message parser / writer to customize the way HTTP

        // messages are parsed from and written out to the data stream.

        HttpMessageParserFactory<HttpResponse> responseParserFactory = new DefaultHttpResponseParserFactory() {


            @Override

            public HttpMessageParser<HttpResponse> create(

                    SessionInputBuffer buffer,

                    MessageConstraints constraints) {

                LineParser lineParser = new BasicLineParser() {


                    @Override

                    public Header parseHeader(final CharArrayBuffer buffer) {

                        try {

                            return super.parseHeader(buffer);

                        } catch (ParseException ex) {

                            return new BasicHeader(buffer.toString(), null);

                        }

                    }


                };

                return new DefaultHttpResponseParser(buffer, lineParser,

                        DefaultHttpResponseFactory.INSTANCE, constraints) {


                    @Override

                    protected boolean reject(final CharArrayBuffer line,

                            int count) {

                        // try to ignore all garbage preceding a status line infinitely

                        return false;

                    }


                };

            }


        };

        HttpMessageWriterFactory<HttpRequest> requestWriterFactory = new DefaultHttpRequestWriterFactory();


        // Use a custom connection factory to customize the process of

        // initialization of outgoing HTTP connections. Beside standard connection

        // configuration parameters HTTP connection factory can define message

        // parser / writer routines to be employed by individual connections.

        HttpConnectionFactory<HttpRoute, ManagedHttpClientConnection> connFactory = new ManagedHttpClientConnectionFactory(

                requestWriterFactory, responseParserFactory);


        // Client HTTP connection objects when fully initialized can be bound to

        // an arbitrary network socket. The process of network socket initialization,

        // its connection to a remote address and binding to a local one is controlled

        // by a connection socket factory.


        // SSL context for secure connections can be created either based on

        // system or application specific properties.

        SSLContext sslcontext = SSLContexts.createSystemDefault();


        // Create a registry of custom connection socket factories for supported

        // protocol schemes.

        Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder

                .<ConnectionSocketFactory> create()

                .register("http", PlainConnectionSocketFactory.INSTANCE)

                .register("https",

                        new SSLConnectionSocketFactory(sslcontext)).build();


        // Use custom DNS resolver to override the system DNS resolution.

        DnsResolver dnsResolver = new SystemDefaultDnsResolver() {


            @Override

            public InetAddress[] resolve(final String host)

                    throws UnknownHostException {

                if (host.equalsIgnoreCase("myhost")) {

                    return new InetAddress[] { InetAddress

                            .getByAddress(new byte[] { 127, 0, 0, 1 }) };

                } else {

                    return super.resolve(host);

                }

            }


        };


        // Create a connection manager with custom configuration.

        PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager(

                socketFactoryRegistry, connFactory, dnsResolver);


        // Create socket configuration

        SocketConfig socketConfig = SocketConfig.custom()

                .setTcpNoDelay(true).build();

        // Configure the connection manager to use socket configuration either

        // by default or for a specific host.

        connManager.setDefaultSocketConfig(socketConfig);

        connManager.setSocketConfig(new HttpHost("somehost", 80),

                socketConfig);

        // Validate connections after 1 sec of inactivity

        connManager.setValidateAfterInactivity(1000);


        // Create message constraints

        MessageConstraints messageConstraints = MessageConstraints.custom()

                .setMaxHeaderCount(200).setMaxLineLength(2000).build();

        // Create connection configuration

        ConnectionConfig connectionConfig = ConnectionConfig.custom()

                .setMalformedInputAction(CodingErrorAction.IGNORE)

                .setUnmappableInputAction(CodingErrorAction.IGNORE)

                .setCharset(Consts.UTF_8)

                .setMessageConstraints(messageConstraints).build();

        // Configure the connection manager to use connection configuration either

        // by default or for a specific host.

        connManager.setDefaultConnectionConfig(connectionConfig);

        connManager.setConnectionConfig(new HttpHost("somehost", 80),

                ConnectionConfig.DEFAULT);


        // Configure total max or per route limits for persistent connections

        // that can be kept in the pool or leased by the connection manager.

        connManager.setMaxTotal(100);

        connManager.setDefaultMaxPerRoute(10);

        connManager.setMaxPerRoute(new HttpRoute(new HttpHost("somehost",

                80)), 20);


        // Use custom cookie store if necessary.

        CookieStore cookieStore = new BasicCookieStore();

        // Use custom credentials provider if necessary.

        CredentialsProvider credentialsProvider = new BasicCredentialsProvider();

        // Create global request configuration

        RequestConfig defaultRequestConfig = RequestConfig

                .custom()

                .setCookieSpec(CookieSpecs.DEFAULT)

                .setExpectContinueEnabled(true)

                .setTargetPreferredAuthSchemes(

                        Arrays.asList(AuthSchemes.NTLM, AuthSchemes.DIGEST))

                .setProxyPreferredAuthSchemes(

                        Arrays.asList(AuthSchemes.BASIC)).build();


        // Create an HttpClient with the given custom dependencies and configuration.

        CloseableHttpClient httpclient = HttpClients.custom()

                .setConnectionManager(connManager)

                .setDefaultCookieStore(cookieStore)

                .setDefaultCredentialsProvider(credentialsProvider)

                .setProxy(new HttpHost("myproxy", 8080))

                .setDefaultRequestConfig(defaultRequestConfig).build();


        try {

            HttpGet httpget = new HttpGet("http://www.apache.org/");

            // Request configuration can be overridden at the request level.

            // They will take precedence over the one set at the client level.

            RequestConfig requestConfig = RequestConfig

                    .copy(defaultRequestConfig).setSocketTimeout(5000)

                    .setConnectTimeout(5000)

                    .setConnectionRequestTimeout(5000)

                    .setProxy(
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