httpClient的post方法使用form格式數據調用接口

Http使用post調用接口，接口只接受form表單數據格式問題？

這個問題的關鍵是form表單提交的是數據格式是什么樣子的，使用httpClient工具類時Header信息如何寫。

會影響解決問題思路的因素：

1、         一致以來都是使用json數據格式調用接口的，form表單是什么格式一時向不起來。

2、         使用form表單數據情況，多是在前台頁面使用form表單提交，或使用JavaScript中的FormData對象處理提交。如果是后台httpClient工具接口如何提交

解決思路：

1、先百度看網上怎么說的，找到一個有用的帖子：https://www.cnblogs.com/zhang-can/p/7631262.html 中有一句：

ajax發送的data是個字典，是鍵值對的形式，在http的post請求過程中，把這種鍵值對轉換成

k1=xxx&k2=xxx這種格式，並且會帶上一個請求頭：

content-type : application/x-www-form-urlencoded

2、 前台訪問后台實際實現也是http協議，那使用谷歌的調試工具，模擬一個form表單提交看看請求header和Form Data的情況：

 

點擊“view source”顯示的格式：

 

這是我們熟悉的格式。

根據上面的測試，修改httpClient的post工具類：

關鍵的地方是：post請求的Header設置

httpPost.addHeader("Content-type", "application/x-www-form-urlencoded; charset=utf-8");

在post中的參數格式為：param1=小明&param2=12

調用時實例：

HttpRequestUtil.post(url地址
        , “param1=小明&param2=12”);

 

測試結果：

返回參數：{"data":{},"code":"0","msg":"處理成功"}

工具類代碼：

import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.nio.charset.Charset;

/**
 * Created by guoyanan on 2018/8/7 0007.
 * 接口調用工具類
 */
public class HttpRequestUtil {
    private static CloseableHttpClient httpClient;

    static {
        PoolingHttpClientConnectionManager cm = new PoolingHttpClientConnectionManager();
        cm.setMaxTotal(100);
        cm.setDefaultMaxPerRoute(20);
        cm.setDefaultMaxPerRoute(50);
        httpClient = HttpClients.custom().setConnectionManager(cm).build();
    }

    public static String get(String url) {
        CloseableHttpResponse response = null;
        BufferedReader in = null;
        String result = "";
        try {
            HttpGet httpGet = new HttpGet(url);
            RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(30000).setConnectionRequestTimeout(30000).setSocketTimeout(30000).build();
            httpGet.setConfig(requestConfig);
            httpGet.setConfig(requestConfig);
            httpGet.addHeader("Content-type", "application/json; charset=utf-8");
            httpGet.setHeader("Accept", "application/json");
            response = httpClient.execute(httpGet);
            in = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
            StringBuffer sb = new StringBuffer("");
            String line = "";
            String NL = System.getProperty("line.separator");
            while ((line = in.readLine()) != null) {
                sb.append(line + NL);
            }
            in.close();
            result = sb.toString();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (null != response) {
                    response.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return result;
    }

    public static String post(String url, String jsonString) {
        CloseableHttpResponse response = null;
        BufferedReader in = null;
        String result = "";
        try {
            HttpPost httpPost = new HttpPost(url);
            RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(30000).setConnectionRequestTimeout(30000).setSocketTimeout(30000).build();
            httpPost.setConfig(requestConfig);
            httpPost.setConfig(requestConfig);
            httpPost.addHeader("Content-type", "application/x-www-form-urlencoded; charset=utf-8");
            httpPost.setHeader("Accept", "application/json");
            httpPost.setEntity(new StringEntity(jsonString, Charset.forName("UTF-8")));

            response = httpClient.execute(httpPost);
            in = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
            StringBuffer sb = new StringBuffer("");
            String line = "";
            String NL = System.getProperty("line.separator");
            while ((line = in.readLine()) != null) {
                sb.append(line + NL);
            }
            in.close();
            result = sb.toString();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (null != response) {
                    response.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return result;
    }

}