java模擬http/https post請求

1.Post請求失敗的代碼

try {
             HttpResponse response = httpClient.execute(httpPost);
 
             HttpEntity entity = response.getEntity();
 
             result = EntityUtils.toString(entity, "UTF-8");
             Util.log("API，POST回來的數據是：");
             Util.log(result);
 
         } catch (ConnectionPoolTimeoutException e) {
             log.e("http get throw ConnectionPoolTimeoutException(wait time out)");
 
         } catch (ConnectTimeoutException e) {
             log.e("http get throw ConnectTimeoutException");
 
         } catch (SocketTimeoutException e) {
             log.e("http get throw SocketTimeoutException");
 
         }  catch (Exception e) {
             log.e("http get throw Exception");
 
         } finally {
             httpPost.abort();
         }

之前每次代碼執行到上述代碼的第二行的時候，會等一段時間然后會捕獲到Exception異常。

2.分析問題

當然捕獲的Exception這個異常太大了我們不便於分析，我們查看一下httpClient.execute(HttpUriRequest uri)的方法；

發下這個方法會拋出IOException, ClientProtocolException這兩個異常，但是在調用方法的時候並沒有明確捕獲他們兩個。

3.得出結論

所以很有可能在執行post請求的過程中，遇到了這兩個問題，果然我們把代碼完善之后

try {
            httpClient = new SSLClient();
            HttpResponse response = httpClient.execute(httpPost);

            HttpEntity entity = response.getEntity();

            result = EntityUtils.toString(entity, "UTF-8");
            Util.log("API，POST回來的數據是：");
            Util.log(result);

        } catch (ConnectionPoolTimeoutException e) {
            log.e("http get throw ConnectionPoolTimeoutException(wait time out)");

        } catch (ConnectTimeoutException e) {
            log.e("http get throw ConnectTimeoutException");

        } catch (SocketTimeoutException e) {
            log.e("http get throw SocketTimeoutException");

        } catch (ClientProtocolException e) {
            log.e("http get throw ClientProtocolException");

        } catch (IOException e) {
            e.printStackTrace();

        } catch (Exception e) {
            log.e("http get throw Exception");

        } finally {
            httpPost.abort();
        }

上述，完善完畢代碼后捕捉到了IOException異常，我們把異常打印出來看到了如下信息。

 4.解決問題

通過在網上查詢可知，這是缺少安全證書時出現的異常，解決方案如下：

1. 等待Oracle/Google/Mozilla等等組織信任CNNIC，算了，洗洗睡吧
2. 使用Java的TrustManager忽略所有的SSL請求的證書，僅僅用於開發測試，限於篇幅不做介紹了
3. 導入目標網站的證書，然后在開始調用之前，指定keystore就ok了，本文介紹下該方法

目前我們采用第二種方案：由於請求的URL是HTTPS的，為了避免需要證書，所以用一個類繼承DefaultHttpClient類，忽略校驗過程。

編寫一個SSLClient類

package com.phicomm.smarthome.sharedwifi.util;

import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;

import javax.net.ssl.SSLContext;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;

import org.apache.http.conn.ClientConnectionManager;
import org.apache.http.conn.scheme.Scheme;
import org.apache.http.conn.scheme.SchemeRegistry;
import org.apache.http.conn.ssl.SSLSocketFactory;
import org.apache.http.impl.client.DefaultHttpClient;

public class SSLClient extends DefaultHttpClient {

    public SSLClient() throws Exception {
        super();
        SSLContext ctx = SSLContext.getInstance("TLS");
        X509TrustManager tm = new X509TrustManager() {

            @Override
            public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
                // TODO Auto-generated method stub

            }

            @Override
            public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
                // TODO Auto-generated method stub

            }

            @Override
            public X509Certificate[] getAcceptedIssuers() {
                // TODO Auto-generated method stub
                return null;
            }
        };
        ctx.init(null, new TrustManager[] { tm }, null);
        SSLSocketFactory ssf = new SSLSocketFactory(ctx, SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);
        ClientConnectionManager ccm = this.getConnectionManager();
        SchemeRegistry sr = ccm.getSchemeRegistry();
        sr.register(new Scheme("https", 443, ssf));
    }
}

 對應的實現類：

public HttpResponse sendPostToService(String url, Object pushData) throws IOException, KeyStoreException,
            UnrecoverableKeyException, NoSuchAlgorithmException, KeyManagementException {

        if (!hasInit) {
            init();
        }

        String result = null;

        HttpPost httpPost = new HttpPost(url);

        StringEntity postEntity = new StringEntity(pushData.toString(),
                ContentType.create("application/x-www-form-urlencoded", "UTF-8"));
        // 設置一些Http頭信息
        httpPost.addHeader("Content-Type", "application/x-www-form-urlencoded");
        httpPost.addHeader("connection", "Keep-Alive");
        httpPost.addHeader("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
        // 將發送內容填裝
        httpPost.setEntity(postEntity);

        // 設置請求器的配置
        httpPost.setConfig(requestConfig);

        // 打印待發送的數據
        Util.log("=====API，POST過去的數據是：");
        Util.log("executing request" + httpPost.getRequestLine());
        Util.log("請求頭信息===" + httpPost.getAllHeaders().toString());
        Util.log("請求狀態行===" + httpPost.getRequestLine());
        Util.log("請求配置===" + httpPost.getConfig());
        Util.log("請求實體===" + httpPost.getEntity().getContentEncoding() + httpPost.getEntity().getContentType()
                + httpPost.getEntity().getContent());

        HttpResponse response = null;
        try {
            // 忽略所有的SSL請求的證書
            httpClient = new SSLClient();
            response = httpClient.execute(httpPost);

            HttpEntity entity = response.getEntity();

            result = EntityUtils.toString(entity, "UTF-8");
            // 打印得到的響應信息
            Util.log("API，POST回來的數據是：");
            Util.log("=====Entity:" + result);
            Util.log("=====Headers:" + response.getAllHeaders());
            Util.log("=====StatusLine:" + response.getStatusLine());
            Util.log("=====Locale:" + response.getLocale());

        } catch (ConnectionPoolTimeoutException e) {
            log.e("http get throw ConnectionPoolTimeoutException(wait time out)");

        } catch (ConnectTimeoutException e) {
            log.e("http get throw ConnectTimeoutException");

        } catch (SocketTimeoutException e) {
            log.e("http get throw SocketTimeoutException");

        } catch (ClientProtocolException e) {
            log.e("http get throw ClientProtocolException");

        } catch (IOException e) {
            e.printStackTrace();

        } catch (Exception e) {
            log.e("http get throw Exception");

        } finally {
            httpPost.abort();
        }

        return response;
    }

在第36行使用自定義的SSLClient來忽略掉驗證要求

另外注意在postMan中模擬調用的時候我們是用的x-www-form-urlencoded格式的數據請求，就是application/x-www-from-urlencoded,會將表單內的數據轉換為鍵值對。

當action為get時候，瀏覽器用x-www-form-urlencoded的編碼方式把form數據轉換成一個字串（name1=value1&name2=value2...），然后把這個字串append到url后面，用?分割，加載這個新的url。 當action為post時候，瀏覽器把form數據封裝到http body中，然后發送到server。 

所以我們需要對傳進來的數據做一下處理：

// 拼接x-www-form-urlencoded格式的請求參數
        String www_url = "coverimg=" + pushMsgModel.getCoverimg() + "&mode=" + pushMsgModel.getMode() + "&msgcontent="
                + pushMsgModel.getMsgContent() + "&msgtype=" + pushMsgModel.getMsgtype() + "&outline="
                + pushMsgModel.getOutline() + "&saveRecord=" + pushMsgModel.getSaveRecord() + "&source="
                + pushMsgModel.getSource() + "&ticker=" + pushMsgModel.getTicker() + "&timestamp="
                + pushMsgModel.getTimestamp() + "&title=" + pushMsgModel.getTitle() + "&uid=" + pushMsgModel.getUid()
                + "&url=" + pushMsgModel.getUrl();
        logger.info("x-www-form-urlencoded格式的請求參數為：" + www_url);

最后效果如下：