HttpClient簡單介紹

public class HttpClientUtil {

    private static PoolingHttpClientConnectionManager connectionManager = null;

    private static IdleConnectionMonitorThread scan = null;

    private static int MAX_CONN_TOTAL = 1000;
    private static int MAX_CONN_PERROUTE = 600;

    public static HttpClientResponseEntity webRequestToServer(String requestUri, String method, byte[] requestData, final int timeOut, String encodeName, Map<String, String> headers) throws Exception {

        HttpClientResponseEntity responseEntity = new HttpClientResponseEntity();
        CloseableHttpResponse response = null;
        InputStream inputStream = null;
        HttpUriRequest httpUriRequest = null;

        try {
            //設置協議http和https對應的處理socket鏈接工廠對象
            SSLContext sslContext = SSLContexts.custom().loadTrustMaterial(null, new TrustSelfSignedStrategy() {
                @Override
                public boolean isTrusted(X509Certificate[] chain, String authType) throws CertificateException {
                    return true;
                }
            }).build();

            SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslContext, new String[]{"SSLv2Hello", "SSLv3", "TLSv1", "TLSv1.1", "TLSv1.2"}, null, NoopHostnameVerifier.INSTANCE);
            Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory>create()
                    .register("http", PlainConnectionSocketFactory.INSTANCE)
                    .register("https", sslsf)
                    .build();
            RequestConfig requestConfig = RequestConfig.custom()
                    .setConnectTimeout(timeOut)
                    .setSocketTimeout(timeOut)
                    .setConnectionRequestTimeout(timeOut)
                    .build();
            SocketConfig socketConfig = SocketConfig.custom()
                    .setSoTimeout(timeOut)
                    .build();
            if (connectionManager == null) {
                connectionManager = new PoolingHttpClientConnectionManager(socketFactoryRegistry);
                connectionManager.setMaxTotal(MAX_CONN_TOTAL);
                connectionManager.setDefaultMaxPerRoute(MAX_CONN_PERROUTE);
            }
            if (scan == null) {
                //清理無效的連接
                scan = new IdleConnectionMonitorThread(connectionManager);
                scan.start();
            }
            HttpClientBuilder httpClientBuilder = HttpClientBuilder.create();
            httpClientBuilder.setConnectionManager(connectionManager);
            httpClientBuilder.setDefaultRequestConfig(requestConfig);
            httpClientBuilder.setDefaultSocketConfig(socketConfig);
            httpClientBuilder.setRetryHandler(new DefaultHttpRequestRetryHandler(0, false));
            httpClientBuilder.setKeepAliveStrategy(new ConnectionKeepAliveStrategy() {
                @Override
                public long getKeepAliveDuration(HttpResponse response, HttpContext context) {
                    final HeaderElementIterator it = new BasicHeaderElementIterator(response.headerIterator(HTTP.CONN_KEEP_ALIVE));
                    while (it.hasNext()) {
                        final HeaderElement he = it.nextElement();
                        final String param = he.getName();
                        final String value = he.getValue();
                        if (value != null && param.equalsIgnoreCase("timeout")) {
                            try {
                                return Long.parseLong(value) * 1000;
                            } catch (final NumberFormatException ignore) {
                            }
                        }
                    }
                    return timeOut;
                }
            });
            CloseableHttpClient httpClient = httpClientBuilder.build();
            switch (method) {
                case "POST":
                    HttpPost httpPost = new HttpPost(requestUri);
                    httpPost.setEntity(new ByteArrayEntity(requestData));
                    if (headers != null) {
                        for (Map.Entry<String, String> entry : headers.entrySet()) {
                            httpPost.setHeader(entry.getKey(), entry.getValue());
                        }
                    }
                    httpUriRequest = httpPost;
                    break;
                case "GET":
                    HttpGet httpGet = new HttpGet(requestUri);
                    if (headers != null) {
                        for (Map.Entry<String, String> entry : headers.entrySet()) {
                            httpGet.setHeader(entry.getKey(), entry.getValue());
                        }
                    }
                    httpUriRequest = httpGet;
                    break;
                default:
                    throw new Exception("請求方式不存在！");

            }
            response = httpClient.execute(httpUriRequest);
            inputStream = response.getEntity().getContent();
            responseEntity.setResponseCode(String.valueOf(response.getStatusLine().getStatusCode()));
            if (HttpStatus.SC_OK == response.getStatusLine().getStatusCode()) {
                ByteArrayOutputStream swapStream = new ByteArrayOutputStream();
                byte[] buff = new byte[1000];
                int ri = 0;
                while ((ri = inputStream.read(buff, 0, 1000)) > 0) {
                    swapStream.write(buff, 0, ri);
                }
                responseEntity.setResponseByteArray(swapStream.toByteArray());
                responseEntity.setResponseBody(new String(responseEntity.getResponseByteArray(), encodeName));
            } else {
                responseEntity.setResponseMsg(response.getStatusLine().getReasonPhrase());
            }
            inputStream.close();
        } catch (Exception e) {
            responseEntity.setResponseCode("-1");
            responseEntity.setResponseMsg(e.getMessage());
            if (e instanceof SocketTimeoutException) {
                responseEntity.setResponseCode("timeout");
                responseEntity.setResponseMsg("介面超時（超時時間：" + timeOut + "毫秒）");
            }
        } finally {
            if (httpUriRequest != null) {
                httpUriRequest.abort();
            }
            if (response != null) {
                EntityUtils.consumeQuietly(response.getEntity());
            }
        }
        return responseEntity;
    }
}

使用 PoolingHttpClientConnectionManager 鏈接池管理類