基于线程池创建HttpClient的请求

代码语言:javascript
复制
public class HttpClientUtils {

    private final static Logger logger = LoggerFactory.getLogger(HttpClientUtils.class);
    private static CloseableHttpClient httpClient;
    private static PoolingHttpClientConnectionManager manager; // 连接池管理类
    private static ScheduledExecutorService monitorExecutor; // 监控
    private final static Object syncLock = new Object(); // 相当于线程锁,用于线程安全
    private static final int CONNECT_TIMEOUT = HttpClientConfig.httpConnectTimeout;// 设置连接建立的超时时间为10s
    private static final int SOCKET_TIMEOUT = HttpClientConfig.httpSocketTimeout;
    private static final int MAX_CONN = HttpClientConfig.httpMaxPoolSize; // 最大连接数
    private static final int Max_PRE_ROUTE = HttpClientConfig.httpMaxPoolSize;
    private static final int MAX_ROUTE = HttpClientConfig.httpMaxPoolSize;


    /**
     * 对http请求进行基本设置
     *
     * @param httpRequestBase http请求
     */
    public 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];
        int port = 80;
        if (hostName.contains(":")) {
            String[] args = hostName.split(":");
            hostName = args[0];
            port = Integer.parseInt(args[1]);
        }
        if (httpClient == null) {
            // 多线程下多个线程同时调用getHttpClient容易导致重复创建httpClient对象的问题
            synchronized (syncLock) {
                if (httpClient == null) {
                    httpClient = createHttpClient(hostName, port);
                    // 开启监控线程,对异常和空闲线程进行关闭
                    monitorExecutor = Executors.newScheduledThreadPool(1);
                    monitorExecutor.scheduleAtFixedRate(new TimerTask() {
                                                            @Override
                                                            public void run() {
                                                                // 关闭异常连接
                                                                manager.closeExpiredConnections();
                                                                // 关闭5s空闲的连接
                                                                manager.closeIdleConnections(HttpClientConfig.httpIdelTimeout, TimeUnit.MILLISECONDS);
                                                                // logger.info("close expired and idle for over 5s connection");
                                                            }
                                                        }, HttpClientConfig.httpMonitorInterval, HttpClientConfig.httpMonitorInterval,
                            TimeUnit.MILLISECONDS);
                }
            }
        }
        return httpClient;
    }

    /**
     * 根据host和port构建httpclient实例
     *
     * @param host 要访问的域名
     * @param port 要访问的端口
     * @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);
        // 设置连接参数
        manager.setMaxTotal(MAX_CONN); // 最大连接数
        manager.setDefaultMaxPerRoute(Max_PRE_ROUTE); // 路由最大连接数
        HttpHost httpHost = new HttpHost(host, port);
        manager.setMaxPerRoute(new HttpRoute(httpHost), MAX_ROUTE);
        // 请求失败时,进行请求重试
        HttpRequestRetryHandler handler = new HttpRequestRetryHandler() {
            @Override
            public boolean retryRequest(IOException e, int i, HttpContext httpContext) {
                if (i > 3) {
                    // 重试超过3次,放弃请求
                    logger.error("retry has more than 3 time, give up request");
                    return false;
                }
                if (e instanceof NoHttpResponseException) {
                    // 服务器没有响应,可能是服务器断开了连接,应该重试
                    logger.error("receive no response from server, retry");
                    return true;
                }
                if (e instanceof SSLHandshakeException) {
                    // SSL握手异常
                    logger.error("SSL hand shake exception");
                    return false;
                }
                if (e instanceof InterruptedIOException) {
                    // 超时
                    logger.error("InterruptedIOException");
                    return false;
                }
                if (e instanceof UnknownHostException) {
                    // 服务器不可达
                    logger.error("server host unknown");
                    return false;
                }
                if (e instanceof ConnectTimeoutException) {
                    // 连接超时
                    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)) {
                    // 如果请求不是关闭连接的请求
                    return true;
                }
                return false;
            }
        };
        CloseableHttpClient client = HttpClients.custom().setConnectionManager(manager).setRetryHandler(handler)
                .build();
        return client;
    }

    /**
     * 关闭连接池
     */
    public static void closeConnectionPool() {
        try {
            httpClient.close();
            manager.close();
            monitorExecutor.shutdown();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}