HttpClient 调用时的采坑记录及解决办法

ゝ一世哀愁。 2022-03-18 03:52 71阅读 0赞

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();
    }