HttpClient 调用时的采坑记录及解决办法-摩杜云开发者社区

1、首先，https是颁发给域名的，如果采取 ip加https访问的机制，会出现证书不安全的问题，直接使用HttpClient去连接会出现客户端无法信任服务器的问题。
解决思想：如果我们去调用这种服务器，从实现上，我们知道这个服务器应该是可信的，所以可以实现忽略这种判断。

public class MySSLSocketFactory extends SSLSocketFactory {

    SSLContext sslContext = SSLContext.getInstance("TLS");

    /**
     *
     * @param truststore
     * @throws NoSuchAlgorithmException
     * @throws KeyManagementException
     * @throws KeyStoreException
     * @throws UnrecoverableKeyException
     */
    public MySSLSocketFactory(KeyStore truststore) throws NoSuchAlgorithmException, KeyManagementException, KeyStoreException, UnrecoverableKeyException {
        super(truststore);

        TrustManager tm = new X509TrustManager() {
            public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
            }

            public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
            }

            public X509Certificate[] getAcceptedIssuers() {
                return null;
            }
        };
        sslContext.init(null, new TrustManager[] { tm }, null);
    }
    @Override
    public Socket createSocket(Socket socket, String host, int port, boolean autoClose) throws IOException, UnknownHostException {
        return sslContext.getSocketFactory().createSocket(socket, host, port, autoClose);
    }
    @Override
    public Socket createSocket() throws IOException {
        return sslContext.getSocketFactory().createSocket();
    }

    /**
     * 在使用时直接调用它即可,,,, 直接得略过https的ssl验证过程
     * @return
     */
    public static HttpClient getNewHttpClient() {
        try {
            KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType());
            trustStore.load(null, null);

            SSLSocketFactory sf = new MySSLSocketFactory(trustStore);
            sf.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);

            HttpParams params = new BasicHttpParams();
            HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
            HttpProtocolParams.setContentCharset(params, HTTP.UTF_8);

            SchemeRegistry registry = new SchemeRegistry();
            registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
            registry.register(new Scheme("https", sf, 443));

            ClientConnectionManager ccm = new ThreadSafeClientConnManager(params, registry);

            return new DefaultHttpClient(ccm, params);
        } catch (Exception e) {
            return new DefaultHttpClient();
        }
    }
}

然后，在你创建httpClient的时候使用这个方法去创建就可以了，例如：

HttpClient httpclient = MySSLSocketFactory.getNewHttpClient();
CredentialsProvider credsProvider = new BasicCredentialsProvider();
((DefaultHttpClient)httpclient).setCredentialsProvider(credsProvider);

2、如果从服务器返回的网页是乱码，这个时候你首先得注意一下编码问题，如果编码没有问题。查看服务器的返回头信息中有没有说gzip等信息，如果有，说明网页被压缩了，解压即可。例如下面这个方法

String body = "";
HttpEntity httpEntity = response.getEntity();
if (Objects.nonNull(httpEntity)) {
    InputStream is = httpEntity.getContent();
    is = new GZIPInputStream(is);//解压缩
    BufferedReader reader = new BufferedReader(new InputStreamReader(is, "utf-8"));
    String str = null;
    StringBuffer stringBuffer = new StringBuffer();
    while (Objects.nonNull(str = reader.readLine())) {
        if (StringUtils.isBlank(str)) {
            continue;
        }
        stringBuffer.append(str);
    }
    body = stringBuffer.toString();
}

3、如果你需要登录某网站获取cookie然后直接利用这个cookie访问别的接口，可以使用如下办法：

// 获取cookieStore
cookieStore = ((DefaultHttpClient) httpclient).getCookieStore();
// 设置cookieStore
((DefaultHttpClient) httpclient).setCookieStore(cookieStore);

不需要把cookie取出来自己操作，只需要保存一个对象属性cookieStore即可

4、HttpGet或者HttpPost绑定参数

// httpget demo
param.add(new BasicNameValuePair("xxxx", xxxx));
param.add(new BasicNameValuePair("yyyy", yyyy));
param.add(new BasicNameValuePair("zzzz", zzzz));
param.add(new BasicNameValuePair("wwww", wwww));
String paramStr = "";
try {
    paramStr = EntityUtils.toString(new UrlEncodedFormEntity(param, "UTF-8"));
} catch (IOException e) {
    e.printStackTrace();
}
String loginUrl1 = loginUrl + paramStr;
HttpGet httpget = new HttpGet(loginUrl1);

// httppost demo
HttpPost httpPost = new HttpPost(url);
param.add(new BasicNameValuePair("xxxx", xxxx));
param.add(new BasicNameValuePair("yyyy", yyyy));

param.add(new BasicNameValuePair("zzzz", zzzz));
param.add(new BasicNameValuePair("wwww", wwww));
try {
    httpPost.setEntity(new UrlEncodedFormEntity(param, "UTF-8"));
} catch (UnsupportedEncodingException e) {
    e.printStackTrace();
}