httpClient連接池

package com.my.client.utils;

import org.apache.http.*;
import org.apache.http.client.HttpRequestRetryHandler;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpRequestBase;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.config.Registry;
import org.apache.http.config.RegistryBuilder;
import org.apache.http.conn.ConnectTimeoutException;
import org.apache.http.conn.routing.HttpRoute;
import org.apache.http.conn.socket.ConnectionSocketFactory;
import org.apache.http.conn.socket.LayeredConnectionSocketFactory;
import org.apache.http.conn.socket.PlainConnectionSocketFactory;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.apache.http.protocol.HttpContext;
import org.apache.http.util.EntityUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLHandshakeException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InterruptedIOException;
import java.net.UnknownHostException;
import java.nio.charset.UnsupportedCharsetException;
import java.util.*;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

/**
 * @author 木西.
 *
 */
public class HttpConnectionPoolUtil {
    private static Logger logger = LoggerFactory.getLogger(HttpConnectionPoolUtil.class);
    private static final int CONNECT_TIMEOUT = Config.getHttpConnectTimeout();// 設置連接建立的超時時間為10s
    private static final int SOCKET_TIMEOUT = Config.getHttpSocketTimeout();
    private static final int MAX_CONN = Config.getHttpMaxPoolSize(); // 最大連接數
    private static final int Max_PRE_ROUTE = Config.getHttpMaxPoolSize();
    private static final int MAX_ROUTE = Config.getHttpMaxPoolSize();
    private static CloseableHttpClient httpClient; // 發送請求的客戶端單例
    private static PoolingHttpClientConnectionManager manager; // 連接池管理類
    private static ScheduledExecutorService monitorExecutor;

    private final static Object syncLock = new Object(); // 相當於線程鎖,用於線程安全

    /**
     * 對http請求進行基本設置
     * 
     * @param httpRequestBase http請求
     */
    private static void setRequestConfig(HttpRequestBase httpRequestBase) {
        RequestConfig requestConfig = RequestConfig.custom().setConnectionRequestTimeout(CONNECT_TIMEOUT)
                .setConnectTimeout(CONNECT_TIMEOUT).setSocketTimeout(SOCKET_TIMEOUT).build();

        httpRequestBase.setConfig(requestConfig);
    }

    public static CloseableHttpClient getHttpClient(String url) {
        String hostName = url.split("/")[2];
        System.out.println(hostName);
        int port = 80;
        if (hostName.contains(":")) {
            String[] args = hostName.split(":");
            hostName = args[0];
            port = Integer.parseInt(args[1]);
        }

        if (httpClient == null) {
            // 多線程下多個線程同時調用getHttpClient容易導致重復創建httpClient對象的問題,所以加上了同步鎖
            synchronized (syncLock) {
                if (httpClient == null) {
                    httpClient = createHttpClient(hostName, port);
                    // 開啟監控線程,對異常和空閑線程進行關閉
                    monitorExecutor = Executors.newScheduledThreadPool(1);
                    monitorExecutor.scheduleAtFixedRate(new TimerTask() {
                        @Override
                        public void run() {
                            // 關閉異常連接
                            manager.closeExpiredConnections();
                            // 關閉5s空閑的連接
                            manager.closeIdleConnections(Config.getHttpIdelTimeout(), TimeUnit.MILLISECONDS);
                            logger.info("close expired and idle for over 5s connection");
                        }
                    }, Config.getHttpMonitorInterval(), Config.getHttpMonitorInterval(), TimeUnit.MILLISECONDS);
                }
            }
        }
        return httpClient;
    }

    /**
     * 根據host和port構建httpclient實例
     * 
     * @param host 要訪問的域名
     * @param port 要訪問的端口
     * @return
     */
    public static CloseableHttpClient createHttpClient(String host, int port) {
        ConnectionSocketFactory plainSocketFactory = PlainConnectionSocketFactory.getSocketFactory();
        LayeredConnectionSocketFactory sslSocketFactory = SSLConnectionSocketFactory.getSocketFactory();
        Registry<ConnectionSocketFactory> registry = RegistryBuilder.<ConnectionSocketFactory>create()
                .register("http", plainSocketFactory).register("https", sslSocketFactory).build();

        manager = new PoolingHttpClientConnectionManager(registry);
        // 設置連接參數
        manager.setMaxTotal(MAX_CONN); // 最大連接數
        manager.setDefaultMaxPerRoute(Max_PRE_ROUTE); // 路由最大連接數

        HttpHost httpHost = new HttpHost(host, port);
        manager.setMaxPerRoute(new HttpRoute(httpHost), MAX_ROUTE);

        // 請求失敗時,進行請求重試
        HttpRequestRetryHandler handler = new HttpRequestRetryHandler() {
            @Override
            public boolean retryRequest(IOException e, int i, HttpContext httpContext) {
                if (i > 3) {
                    // 重試超過3次,放棄請求
                    logger.error("retry has more than 3 time, give up request");
                    return false;
                }
                if (e instanceof NoHttpResponseException) {
                    // 服務器沒有響應,可能是服務器斷開了連接,應該重試
                    logger.error("receive no response from server, retry");
                    return true;
                }
                if (e instanceof SSLHandshakeException) {
                    // SSL握手異常
                    logger.error("SSL hand shake exception");
                    return false;
                }
                if (e instanceof InterruptedIOException) {
                    // 超時
                    logger.error("InterruptedIOException");
                    return false;
                }
                if (e instanceof UnknownHostException) {
                    // 服務器不可達
                    logger.error("server host unknown");
                    return false;
                }
                if (e instanceof ConnectTimeoutException) {
                    // 連接超時
                    logger.error("Connection Time out");
                    return false;
                }
                if (e instanceof SSLException) {
                    logger.error("SSLException");
                    return false;
                }

                HttpClientContext context = HttpClientContext.adapt(httpContext);
                HttpRequest request = context.getRequest();
                if (!(request instanceof HttpEntityEnclosingRequest)) {
                    // 如果請求不是關閉連接的請求
                    return true;
                }
                return false;
            }
        };

        CloseableHttpClient client = HttpClients.custom().setConnectionManager(manager).setRetryHandler(handler)
                .build();
        return client;
    }

    /**
     * 設置post請求的參數
     */
    private static void setPostParams(HttpPost httpPost, Map<String, String> params) {
        try {
            httpPost.setEntity(new StringEntity(GsonUtils.toJson(params), ContentType.APPLICATION_JSON));
        } catch (UnsupportedCharsetException e) {
            e.printStackTrace();
        }
    }

    /**
     * 發送post請求
     * */
    public static String post(String url, Map<String, String> params) {
        HttpPost httpPost = new HttpPost(url);
        setRequestConfig(httpPost);
        setPostParams(httpPost, params);
        CloseableHttpResponse response = null;
        InputStream in = null;
        String resp =null;
        try {
            response = getHttpClient(url).execute(httpPost, HttpClientContext.create());
            HttpEntity entity = response.getEntity();
            resp = EntityUtils.toString(entity);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (in != null)
                    in.close();
                if (response != null)
                    response.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return resp;
    }

    /**
     * 關閉連接池
     */
    public static void closeConnectionPool() {
        try {
            httpClient.close();
            manager.close();
            monitorExecutor.shutdown();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

class Config {

    static int httpConnectTimeout = 15*1000;

    static int httpSocketTimeout = 15*1000;

    static int httpMaxPoolSize = 100;

    static int httpMonitorInterval = 10*1000;

    static int httpIdelTimeout = 5*1000;

    public static int getHttpIdelTimeout() {
        return httpIdelTimeout;
    }

    public static int getHttpSocketTimeout() {
        return httpSocketTimeout;
    }

    public static int getHttpMaxPoolSize() {
        return httpMaxPoolSize;
    }

    public static int getHttpMonitorInterval() {
        return httpMonitorInterval;
    }

    public static int getHttpConnectTimeout() {
        return httpConnectTimeout;
    }

}