Java getPost dopost 调用第三方接口

最新推荐文章于 2025-09-17 14:56:21 发布

原创最新推荐文章于 2025-09-17 14:56:21 发布 · 626 阅读

11 ·

CC 4.0 BY-SA版权

文章标签：

#java #开发语言

文章详细介绍了如何使用HttpUtil类在Java中发送GET和POST请求，包括设置请求参数、编码、连接管理以及使用ApacheHttpClient库的替代方法。

HttpUtil工具类

/**
 * URL请求
 */
public class HttpUtil {
    private static String userAgent = "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1)";
    private static String charset = "UTF-8";

    /**
     * 发送GET请求，通过流的形式
     *
     * @param url      目的地址
     * @param paramMap 请求参数，Map类型。
     * @return 远程响应结果
     * @throws IOException
     */
    public static String doGet(String url, Map<String, Object> paramMap) throws IOException {
        String result = "";
        BufferedReader in = null;// 读取响应输入流
        StringBuffer sb = new StringBuffer();// 存储参数
        String params = "";// 编码之后的参数
        try {
            // 编码请求参数
            if (paramMap.size() == 1) {
                for (String name : paramMap.keySet()) {
                    if (paramMap.get(name) != null) {
                        sb.append(name).append("=")
                                .append(java.net.URLEncoder.encode(String.valueOf(paramMap.get(name)), charset));
                    }
                }
                params = sb.toString();
            } else {
                for (String name : paramMap.keySet()) {
                    if (paramMap.get(name) != null) {
                        sb.append(name).append("=")
                                .append(java.net.URLEncoder.encode(String.valueOf(paramMap.get(name)), charset))
                                .append("&");
                    }
                }
                String temp_params = sb.toString();
                params = temp_params.substring(0, temp_params.length() - 1);
            }
            String full_url = url + "?" + params;
            // 创建URL对象
            java.net.URL connURL = new java.net.URL(full_url);
            // 打开URL连接
            java.net.HttpURLConnection httpConn = (java.net.HttpURLConnection) connURL.openConnection();
            // 设置通用属性
            httpConn.setRequestProperty("Accept", "*/*");
            httpConn.setRequestProperty("Connection", "Keep-Alive");
            httpConn.setRequestProperty("User-Agent", userAgent);
            // 建立实际的连接
            httpConn.connect();
            // 响应头部获取
            Map<String, List<String>> headers = httpConn.getHeaderFields();
            // 遍历所有的响应头字段
            for (String key : headers.keySet()) {
//                CommonUtil.outPrint(key + "\t：\t" + headers.get(key));
            }
            // 定义BufferedReader输入流来读取URL的响应,并设置编码方式
            in = new BufferedReader(new InputStreamReader(httpConn.getInputStream(), charset));
            String line;
            // 读取返回的内容
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            throw e;
        } finally {
            try {
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                throw ex;
            }
        }
        return result;
    }

    /**
     * 发送POST请求
     *
     * @param url      目的地址
     * @param paramMap 请求参数，Map类型。
     * @return 远程响应结果
     * @throws Exception
     */
    public static String doPost(String url, Map<String, String> paramMap) throws Exception {
        String result = "";// 返回的结果
        BufferedReader in = null;// 读取响应输入流
        PrintWriter out = null;
        try {
            StringBuffer params = new StringBuffer();// 处理请求参数
            // 编码请求参数
            for (String name : paramMap.keySet()) {
                String val = paramMap.get(name);
                if (val != null) {
                    params.append(name).append("=")
                            .append(URLEncoder.encode(val, charset))
                            .append("&");
                } else {
                    params.append(name).append("=")
                            .append(URLEncoder.encode("", charset));
                }
            }

            // 创建URL对象
            java.net.URL connURL = new java.net.URL(url);
            // 打开URL连接
            java.net.HttpURLConnection httpConn = (java.net.HttpURLConnection) connURL.openConnection();
            // 设置通用属性
            httpConn.setRequestProperty("Accept", "*/*");
            httpConn.setRequestProperty("Connection", "Keep-Alive");
            httpConn.setRequestProperty("User-Agent", userAgent);
            // 设置POST方式
            httpConn.setDoInput(true);
            httpConn.setDoOutput(true);
            // 获取HttpURLConnection对象对应的输出流
            out = new PrintWriter(httpConn.getOutputStream());
            // 发送请求参数
            out.write(params.toString());
            // flush输出流的缓冲
            out.flush();
            // 定义BufferedReader输入流来读取URL的响应，设置编码方式
            in = new BufferedReader(new InputStreamReader(httpConn.getInputStream(), charset));
            String line;
            // 读取返回的内容
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            throw e;
        } finally {
            try {
                if (out != null) {
                    out.close();
                }
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                throw ex;
            }
        }
        return result;
    }


    /**
     * 向指定URL发送GET方法的请求
     *
     * @param url   发送请求的URL
     * @param param 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
     * @return URL 所代表远程资源的响应结果
     */
    public Object sendGet(String url, String param) {
        String result = "";
        BufferedReader in = null;
        try {
            String urlNameString = url + "?" + param;
            URL realUrl = new URL(urlNameString);
            // 打开和URL之间的连接
            URLConnection connection = realUrl.openConnection();
            // 设置通用的请求属性
            connection.setRequestProperty("accept", "*/*");
            connection.setRequestProperty("connection", "Keep-Alive");
            connection.setRequestProperty("user-agent",
                    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
            // 建立实际的连接
            connection.connect();
            // 获取所有响应头字段
            Map<String, List<String>> map = connection.getHeaderFields();
            // 遍历所有的响应头字段
            for (String key : map.keySet()) {
                System.out.println(key + "--->" + map.get(key));
            }
            // 定义 BufferedReader输入流来读取URL的响应
            in = new BufferedReader(new InputStreamReader(
                    connection.getInputStream()));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            System.out.println("发送GET请求出现异常！" + e);
            e.printStackTrace();
        }
        // 使用finally块来关闭输入流
        finally {
            try {
                if (in != null) {
                    in.close();
                }
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        }
        return result;
    }


    /**
     * 向指定 URL 发送POST方法的请求
     *
     * @param url   发送请求的 URL
     * @param param 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
     * @return 所代表远程资源的响应结果
     */
    public Object sendPost(String url, String param) {
        PrintWriter out = null;
        BufferedReader in = null;
        String result = "";
        try {
            URL realUrl = new URL(url);
            // 打开和URL之间的连接
            URLConnection conn = realUrl.openConnection();
            // 设置通用的请求属性
            conn.setRequestProperty("accept", "*/*");
            conn.setRequestProperty("connection", "Keep-Alive");
            conn.setRequestProperty("user-agent",
                    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
            // 发送POST请求必须设置如下两行
            conn.setDoOutput(true);
            conn.setDoInput(true);
            // 获取URLConnection对象对应的输出流
            out = new PrintWriter(conn.getOutputStream());
            // 发送请求参数
            out.print(param);
            // flush输出流的缓冲
            out.flush();
            // 定义BufferedReader输入流来读取URL的响应
            in = new BufferedReader(
                    new InputStreamReader(conn.getInputStream()));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }

        } catch (Exception e) {
            System.out.println("发送 POST 请求出现异常！" + e);
            e.printStackTrace();
        }
        //使用finally块来关闭输出流、输入流
        finally {
            try {
                if (out != null) {
                    out.close();
                }
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        return result;
    }

/**
 * 发送GET请求，通过HttpClient方式   
 * pom文件需要引入依赖
 * @param url
 * @param param
 * @return
 */
public static String doGet(String url, String param) {
    CloseableHttpClient httpClient = HttpClientBuilder.create().build();
    StringBuffer result = new StringBuffer();
    String realUrl = url;
    if (!param.equals(""))
        realUrl = url + "?" + param;
    HttpGet httpGet = new HttpGet(realUrl);
    try {
        HttpResponse response = httpClient.execute(httpGet);
        HttpEntity entity = response.getEntity();
        InputStreamReader reader = new InputStreamReader(entity.getContent(), charset);
        char[] charbufer;
        while (0 < reader.read(charbufer = new char[10])) {
            result.append(charbufer);
        }
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        httpGet.releaseConnection();
    }
    return result.toString();
}
}

pom文件引入

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.1</version>
</dependency>