java模拟http/https post请求

1.Post请求失败的代码

try {
             HttpResponse response = httpClient.execute(httpPost);
 
             HttpEntity entity = response.getEntity();
 
             result = EntityUtils.toString(entity, "UTF-8");
             Util.log("API，POST回来的数据是：");
             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();
         }

之前每次代码执行到上述代码的第二行的时候，会等一段时间然后会捕获到Exception异常。

2.分析问题

当然捕获的Exception这个异常太大了我们不便于分析，我们查看一下httpClient.execute(HttpUriRequest uri)的方法；

发下这个方法会抛出IOException, ClientProtocolException这两个异常，但是在调用方法的时候并没有明确捕获他们两个。

3.得出结论

所以很有可能在执行post请求的过程中，遇到了这两个问题，果然我们把代码完善之后

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

            HttpEntity entity = response.getEntity();

            result = EntityUtils.toString(entity, "UTF-8");
            Util.log("API，POST回来的数据是：");
            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，完善完毕代码后捕捉到了IOException异常，我们把异常打印出来看到了如下信息。

 4.解决问题

通过在网上查询可知，这是缺少安全证书时出现的异常，解决方案如下：

1. 等待Oracle/Google/Mozilla等等组织信任CNNIC，算了，洗洗睡吧
2. 使用Java的TrustManager忽略所有的SSL请求的证书，仅仅用于开发测试，限于篇幅不做介绍了
3. 导入目标网站的证书，然后在开始调用之前，指定keystore就ok了，本文介绍下该方法

目前我们采用第二种方案：由于请求的URL是HTTPS的，为了避免需要证书，所以用一个类继承DefaultHttpClient类，忽略校验过程。

编写一个SSLClient类

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));
    }
}

 对应的实现类：

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"));
        // 设置一些Http头信息
        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)");
        // 将发送内容填装
        httpPost.setEntity(postEntity);

        // 设置请求器的配置
        httpPost.setConfig(requestConfig);

        // 打印待发送的数据
        Util.log("=====API，POST过去的数据是：");
        Util.log("executing request" + httpPost.getRequestLine());
        Util.log("请求头信息===" + httpPost.getAllHeaders().toString());
        Util.log("请求状态行===" + httpPost.getRequestLine());
        Util.log("请求配置===" + httpPost.getConfig());
        Util.log("请求实体===" + httpPost.getEntity().getContentEncoding() + httpPost.getEntity().getContentType()
                + httpPost.getEntity().getContent());

        HttpResponse response = null;
        try {
            // 忽略所有的SSL请求的证书
            httpClient = new SSLClient();
            response = httpClient.execute(httpPost);

            HttpEntity entity = response.getEntity();

            result = EntityUtils.toString(entity, "UTF-8");
            // 打印得到的响应信息
            Util.log("API，POST回来的数据是：");
            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行使用自定义的SSLClient来忽略掉验证要求

另外注意在postMan中模拟调用的时候我们是用的x-www-form-urlencoded格式的数据请求，就是application/x-www-from-urlencoded,会将表单内的数据转换为键值对。

当action为get时候，浏览器用x-www-form-urlencoded的编码方式把form数据转换成一个字串（name1=value1&name2=value2...），然后把这个字串append到url后面，用?分割，加载这个新的url。 当action为post时候，浏览器把form数据封装到http body中，然后发送到server。 

所以我们需要对传进来的数据做一下处理：

// 拼接x-www-form-urlencoded格式的请求参数
        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格式的请求参数为：" + www_url);

最后效果如下：