【一】、封装HttpClient和Json解析

封装HttpClient和Json解析（这里主要介绍封装的思想，具体的代码实现我会在github中给出）

在实际开发中，我们可能需要调用第三方服务器的接口，这就要使用到HttpClient来发送请求，这里就基于HttpClient封装了比较方便的助手类，并且扩展封装了响应信息的格式化（目前只支持Json格式化，开发者可以自定义格式化方法）

1.首先引入相关的依赖包：

<!--https://mvnrepository.com/artifact/com.alibaba/fastjson--><dependency>    <groupId>com.alibaba</groupId>    <artifactId>fastjson</artifactId>    <version>1.2.29</version></dependency><!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient --><dependency>    <groupId>org.apache.httpcomponents</groupId>    <artifactId>httpclient</artifactId>    <version>4.5.3</version></dependency>

2.目前为止整个工程的目录如下：

这里为了日后扩展，使用了接口的思想，需要解析不同格式的字符串时，只需要在方法中传入解析接口ResponseParser的实现类，自定义具体的解析算法即可，并不需要在原来的代码上修改。

使用方法也很简单，调用的代码如下：

public void testPostRawData2Str() {    Map<String, Object> reqParams = new HashMap<>();    reqParams.put("id", UUID.randomUUID().toString());    Map<String, Object> res = HttpClientHelper.postRawData(url, reqParams);    System.out.println(res);}

最终返回的是一个map集合的结果。

源代码我也在github上面给出：

https://github.com/wulongtao/web-base-master/tree/master/src/main/java/com/xxh/web/util/http

https://github.com/wulongtao/web-base-master/tree/master/src/main/java/com/xxh/web/util/format

主要代码如下：

package com.xxh.web.util.http;import com.alibaba.fastjson.JSONObject;import com.xxh.web.util.format.JsonResponseParser;import com.xxh.web.util.format.ResponseParser;import org.apache.http.HttpEntity;import org.apache.http.client.ClientProtocolException;import org.apache.http.client.methods.CloseableHttpResponse;import org.apache.http.client.methods.HttpPost;import org.apache.http.entity.ContentType;import org.apache.http.entity.StringEntity;import org.apache.http.impl.client.CloseableHttpClient;import org.apache.http.impl.client.HttpClients;import org.apache.http.util.EntityUtils;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import java.io.IOException;import java.util.Map;/** * HttpClient助手类，主要实现了请求响应数据的格式化，方便开发调用 * Created by wulongtao on 2017/5/15. */public class HttpClientHelper {    private static final Logger logger = LoggerFactory.getLogger(HttpClientHelper.class);    private static ResponseParser responseParser = new JsonResponseParser();    /**     * 以rawData形式发送http post请求，Map集合方式返回     * @param url url     * @param reqParams 请求参数     * @return     */    public static Map<String, Object> postRawData(String url, Map<String, Object> reqParams) {        String resp = postRawData2Str(url, reqParams);        return responseParser.parse(resp);    }    /**     * * 以rawData形式发送http post请求，Map集合方式返回     * @param url url     * @param reqParams 请求参数     * @param responseParser ResponseParser的实现类，实现parse方法     * @return     */    public static Map<String, Object> postRawData(String url, Map<String, Object> reqParams, ResponseParser responseParser) {        String resp = postRawData2Str(url, reqParams);        return responseParser.parse(resp);    }    /**     * 以rawData形式发送http post请求，字符串形式返回响应结果     * @param url url     * @param reqParams 请求参数     * @return     */    public static String postRawData2Str(String url, Map<String, Object> reqParams) {        String resp = "";        StringEntity entityStr = new StringEntity(JSONObject.toJSONString(reqParams), ContentType                .create("text/plain", "UTF-8"));        CloseableHttpClient httpClient = HttpClients.createDefault();        HttpPost httpPost = new HttpPost(url);        httpPost.setEntity(entityStr);        CloseableHttpResponse response = null;        try {            response = httpClient.execute(httpPost);            //logger            logger.info("Do post raw data,status line=" + response.getStatusLine());            HttpEntity entity = response.getEntity();            resp = EntityUtils.toString(entity, "UTF-8");            EntityUtils.consume(entity);        } catch (ClientProtocolException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        } finally {            if (response != null) {                try {                    response.close();                } catch (IOException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                }            }        }        if (resp == null || resp.equals("")) {            return "";        }        return resp;    }}

package com.xxh.web.util.format;import java.util.Map;/** * Created by wulongtao on 2017/5/16. */public interface ResponseParser {    /**     * 解析http响应消息，可以扩展解析JSON、XML等格式     * @param resp     * @return     */    Map<String, Object> parse(String resp);}

package com.xxh.web.util.format;import com.alibaba.fastjson.JSONArray;import com.alibaba.fastjson.JSONObject;import java.util.*;/** * Created by wulongtao on 2017/5/16. */public class JsonResponseParser implements ResponseParser {    @Override    public Map<String, Object> parse(String resp) {        JSONObject jsonObject = JSONObject.parseObject(resp);        return parseFromJson(jsonObject);    }    /**     * 根据JSONObject对象解析成Map对象     * @param jsonObject     * @return     */    private Map<String, Object> parseFromJson(JSONObject jsonObject) {        Map<String, Object> mRes = new HashMap<>();        Iterator<Map.Entry<String, Object>> it = jsonObject.entrySet().iterator();        while (it.hasNext()) {            Map.Entry<String, Object> param = it.next();            if (param.getValue() instanceof JSONObject) {                mRes.put(param.getKey(), parseFromJson((JSONObject) param.getValue()));            } else if (param.getValue() instanceof JSONArray) {                mRes.put(param.getKey(), json2List(param.getValue()));            } else {                mRes.put(param.getKey(), param.getValue());            }        }        return mRes;    }    private List<Map<String, Object>> json2List(Object json) {        JSONArray arrJson = (JSONArray) json;        List<Map<String, Object>> lst = new ArrayList<>();        for (int i = 0; i < arrJson.size(); i++) {            lst.add(parseFromJson(arrJson.getJSONObject(i)));        }        return lst;    }}