HttpComponents之httpclient基本使用方法

第一种方式

package http;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class HttpClient2 {

    public static void main(String args[]) throws IOException {
        List formparams = new ArrayList();
        formparams.add(new BasicNameValuePair("account", ""));
        formparams.add(new BasicNameValuePair("password", ""));
        HttpEntity reqEntity = new UrlEncodedFormEntity(formparams, "utf-8");

        RequestConfig requestConfig = RequestConfig.custom()
                .setSocketTimeout(5000)
                .setConnectTimeout(5000)
                .setConnectionRequestTimeout(5000)
                .build();

        HttpClient client = new DefaultHttpClient();
        HttpPost post = new HttpPost("http://cnivi.com.cn/login");
        post.setEntity(reqEntity);
        post.setConfig(requestConfig);
        HttpResponse response = client.execute(post);

        if (response.getStatusLine().getStatusCode() == 200) {
            HttpEntity resEntity = response.getEntity();
            String message = EntityUtils.toString(resEntity, "utf-8");
            System.out.println(message);
        } else {
            System.out.println("请求失败");
        }
    }
}

第二种方式

这种方式是用了一个http的连接池，同时使用httpbuilder构造合适的http方法。

package http;

import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.client.methods.RequestBuilder;
import org.apache.http.conn.routing.HttpRoute;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

import java.io.IOException;
import java.util.*;

public class HttpClientUtils {

    private static PoolingHttpClientConnectionManager connectionManager = null;
    private static HttpClientBuilder httpBulder = null;
    private static RequestConfig requestConfig = null;

    private static int MAXCONNECTION = 10;

    private static int DEFAULTMAXCONNECTION = 5;

    private static String IP = "cnivi.com.cn";
    private static int PORT = 80;

    static {
        //设置http的状态参数
        requestConfig = RequestConfig.custom()
                .setSocketTimeout(5000)
                .setConnectTimeout(5000)
                .setConnectionRequestTimeout(5000)
                .build();

        HttpHost target = new HttpHost(IP, PORT);
        connectionManager = new PoolingHttpClientConnectionManager();
        connectionManager.setMaxTotal(MAXCONNECTION);
        connectionManager.setDefaultMaxPerRoute(DEFAULTMAXCONNECTION);
        connectionManager.setMaxPerRoute(new HttpRoute(target), 20);
        httpBulder = HttpClients.custom();
        httpBulder.setConnectionManager(connectionManager);
    }

    public static CloseableHttpClient getConnection() {
        CloseableHttpClient httpClient = httpBulder.build();
        httpClient = httpBulder.build();
        return httpClient;
    }


    public static HttpUriRequest getRequestMethod(Map map, String url, String method) {
        List params = new ArrayList();
        Set> entrySet = map.entrySet();
        for (Map.Entry e : entrySet) {
            String name = e.getKey();
            String value = e.getValue();
            NameValuePair pair = new BasicNameValuePair(name, value);
            params.add(pair);
        }
        HttpUriRequest reqMethod = null;
        if ("post".equals(method)) {
            reqMethod = RequestBuilder.post().setUri(url)
                    .addParameters(params.toArray(new BasicNameValuePair[params.size()]))
                    .setConfig(requestConfig).build();
        } else if ("get".equals(method)) {
            reqMethod = RequestBuilder.get().setUri(url)
                    .addParameters(params.toArray(new BasicNameValuePair[params.size()]))
                    .setConfig(requestConfig).build();
        }
        return reqMethod;
    }

    public static void main(String args[]) throws IOException {
        Map map = new HashMap();
        map.put("account", "");
        map.put("password", "");

        HttpClient client = getConnection();
        HttpUriRequest post = getRequestMethod(map, "http://cnivi.com.cn/login", "post");
        HttpResponse response = client.execute(post);

        if (response.getStatusLine().getStatusCode() == 200) {
            HttpEntity entity = response.getEntity();
            String message = EntityUtils.toString(entity, "utf-8");
            System.out.println(message);
        } else {
            System.out.println("请求失败");
        }
    }
}

博文转自：https://my.oschina.net/xinxingegeya/blog/282683