Java发送http get/post请求，调用接口/方法

ゞ浴缸里的玫瑰 2022-05-14 03:59 908阅读 0赞

由于项目中要用，所以找了一些资料，整理下来。

GitHub地址: https://github.com/iamyong    转自：http://blog.csdn.net/capmiachael/article/details/51833531

**例1**：使用 HttpClient （commons-httpclient-3.0.jar

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1 import java.io.ByteArrayInputStream;
     2 import java.io.ByteArrayOutputStream;
     3 import java.io.IOException;
     4 import java.io.InputStream;
     5 
     6 import org.apache.commons.httpclient.HttpClient;
     7 import org.apache.commons.httpclient.methods.InputStreamRequestEntity;
     8 import org.apache.commons.httpclient.methods.PostMethod;
     9 import org.apache.commons.httpclient.methods.RequestEntity;
    10 
    11 public class HttpTool {
    12 
    13     /**
    14      * 发送post请求
    15      * 
    16      * @param params
    17      *            参数
    18      * @param requestUrl
    19      *            请求地址
    20      * @param authorization
    21      *            授权书
    22      * @return 返回结果
    23      * @throws IOException
    24      */
    25     public static String sendPost(String params, String requestUrl,
    26             String authorization) throws IOException {
    27 
    28         byte[] requestBytes = params.getBytes("utf-8"); // 将参数转为二进制流
    29         HttpClient httpClient = new HttpClient();// 客户端实例化
    30         PostMethod postMethod = new PostMethod(requestUrl);
    31         //设置请求头Authorization
    32         postMethod.setRequestHeader("Authorization", "Basic " + authorization);
    33         // 设置请求头  Content-Type
    34         postMethod.setRequestHeader("Content-Type", "application/json");
    35         InputStream inputStream = new ByteArrayInputStream(requestBytes, 0,
    36                 requestBytes.length);
    37         RequestEntity requestEntity = new InputStreamRequestEntity(inputStream,
    38                 requestBytes.length, "application/json; charset=utf-8"); // 请求体
    39         postMethod.setRequestEntity(requestEntity);
    40         httpClient.executeMethod(postMethod);// 执行请求
    41         InputStream soapResponseStream = postMethod.getResponseBodyAsStream();// 获取返回的流
    42         byte[] datas = null;
    43         try {
    44             datas = readInputStream(soapResponseStream);// 从输入流中读取数据
    45         } catch (Exception e) {
    46             e.printStackTrace();
    47         }
    48         String result = new String(datas, "UTF-8");// 将二进制流转为String
    49         // 打印返回结果
    50         // System.out.println(result);
    51 
    52         return result;
    53 
    54     }
    55 
    56     /**
    57      * 从输入流中读取数据
    58      * 
    59      * @param inStream
    60      * @return
    61      * @throws Exception
    62      */
    63     public static byte[] readInputStream(InputStream inStream) throws Exception {
    64         ByteArrayOutputStream outStream = new ByteArrayOutputStream();
    65         byte[] buffer = new byte[1024];
    66         int len = 0;
    67         while ((len = inStream.read(buffer)) != -1) {
    68             outStream.write(buffer, 0, len);
    69         }
    70         byte[] data = outStream.toByteArray();
    71         outStream.close();
    72         inStream.close();
    73         return data;
    74     }
    75 }

![复制代码][copycode.gif]

**例2：**

![复制代码][copycode.gif]

1 import java.io.BufferedReader;  
      2 import java.io.IOException;
      3 import java.io.InputStream;  
      4 import java.io.InputStreamReader;  
      5 import java.io.OutputStreamWriter;
      6 import java.io.UnsupportedEncodingException;  
      7 import java.net.HttpURLConnection;  
      8 import java.net.InetSocketAddress;
      9 import java.net.Proxy;
     10 import java.net.URL; 
     11 import java.net.URLConnection;
     12 import java.util.List;
     13 import java.util.Map;
     14 
     15 /** 
     16  * Http请求工具类 
     17  */
     18 public class HttpRequestUtil {
     19     static boolean proxySet = false;
     20     static String proxyHost = "127.0.0.1";
     21     static int proxyPort = 8087;
     22     /** 
     23      * 编码 
     24      * @param source 
     25      * @return 
     26      */ 
     27     public static String urlEncode(String source,String encode) {  
     28         String result = source;  
     29         try {  
     30             result = java.net.URLEncoder.encode(source,encode);  
     31         } catch (UnsupportedEncodingException e) {  
     32             e.printStackTrace();  
     33             return "0";  
     34         }  
     35         return result;  
     36     }
     37     public static String urlEncodeGBK(String source) {  
     38         String result = source;  
     39         try {  
     40             result = java.net.URLEncoder.encode(source,"GBK");  
     41         } catch (UnsupportedEncodingException e) {  
     42             e.printStackTrace();  
     43             return "0";  
     44         }  
     45         return result;  
     46     }
     47     /** 
     48      * 发起http请求获取返回结果 
     49      * @param req_url 请求地址 
     50      * @return 
     51      */ 
     52     public static String httpRequest(String req_url) {
     53         StringBuffer buffer = new StringBuffer();  
     54         try {  
     55             URL url = new URL(req_url);  
     56             HttpURLConnection httpUrlConn = (HttpURLConnection) url.openConnection();  
     57 
     58             httpUrlConn.setDoOutput(false);  
     59             httpUrlConn.setDoInput(true);  
     60             httpUrlConn.setUseCaches(false);  
     61 
     62             httpUrlConn.setRequestMethod("GET");  
     63             httpUrlConn.connect();  
     64 
     65             // 将返回的输入流转换成字符串  
     66             InputStream inputStream = httpUrlConn.getInputStream();  
     67             InputStreamReader inputStreamReader = new InputStreamReader(inputStream, "utf-8");  
     68             BufferedReader bufferedReader = new BufferedReader(inputStreamReader);  
     69 
     70             String str = null;  
     71             while ((str = bufferedReader.readLine()) != null) {  
     72                 buffer.append(str);  
     73             }  
     74             bufferedReader.close();  
     75             inputStreamReader.close();  
     76             // 释放资源  
     77             inputStream.close();  
     78             inputStream = null;  
     79             httpUrlConn.disconnect();  
     80 
     81         } catch (Exception e) {  
     82             System.out.println(e.getStackTrace());  
     83         }  
     84         return buffer.toString();  
     85     }  
     86 
     87     /** 
     88      * 发送http请求取得返回的输入流 
     89      * @param requestUrl 请求地址 
     90      * @return InputStream 
     91      */ 
     92     public static InputStream httpRequestIO(String requestUrl) {  
     93         InputStream inputStream = null;  
     94         try {  
     95             URL url = new URL(requestUrl);  
     96             HttpURLConnection httpUrlConn = (HttpURLConnection) url.openConnection();  
     97             httpUrlConn.setDoInput(true);  
     98             httpUrlConn.setRequestMethod("GET");  
     99             httpUrlConn.connect();  
    100             // 获得返回的输入流  
    101             inputStream = httpUrlConn.getInputStream();  
    102         } catch (Exception e) {  
    103             e.printStackTrace();  
    104         }  
    105         return inputStream;  
    106     }
    107 
    108 
    109     /**
    110      * 向指定URL发送GET方法的请求
    111      * 
    112      * @param url
    113      *            发送请求的URL
    114      * @param param
    115      *            请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
    116      * @return URL 所代表远程资源的响应结果
    117      */
    118     public static String sendGet(String url, String param) {
    119         String result = "";
    120         BufferedReader in = null;
    121         try {
    122             String urlNameString = url + "?" + param;
    123             URL realUrl = new URL(urlNameString);
    124             // 打开和URL之间的连接
    125             URLConnection connection = realUrl.openConnection();
    126             // 设置通用的请求属性
    127             connection.setRequestProperty("accept", "*/*");
    128             connection.setRequestProperty("connection", "Keep-Alive");
    129             connection.setRequestProperty("user-agent",
    130                     "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
    131             // 建立实际的连接
    132             connection.connect();
    133             // 获取所有响应头字段
    134             Map<String, List<String>> map = connection.getHeaderFields();
    135             // 遍历所有的响应头字段
    136             for (String key : map.keySet()) {
    137                 System.out.println(key + "--->" + map.get(key));
    138             }
    139             // 定义 BufferedReader输入流来读取URL的响应
    140             in = new BufferedReader(new InputStreamReader(
    141                     connection.getInputStream()));
    142             String line;
    143             while ((line = in.readLine()) != null) {
    144                 result += line;
    145             }
    146         } catch (Exception e) {
    147             System.out.println("发送GET请求出现异常！" + e);
    148             e.printStackTrace();
    149         }
    150         // 使用finally块来关闭输入流
    151         finally {
    152             try {
    153                 if (in != null) {
    154                     in.close();
    155                 }
    156             } catch (Exception e2) {
    157                 e2.printStackTrace();
    158             }
    159         }
    160         return result;
    161     }
    162 
    163     /**
    164      * 向指定 URL 发送POST方法的请求
    165      * 
    166      * @param url
    167      *            发送请求的 URL
    168      * @param param
    169      *            请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
    170      * @param isproxy
    171      *               是否使用代理模式
    172      * @return 所代表远程资源的响应结果
    173      */
    174     public static String sendPost(String url, String param,boolean isproxy) {
    175         OutputStreamWriter out = null;
    176         BufferedReader in = null;
    177         String result = "";
    178         try {
    179             URL realUrl = new URL(url);
    180             HttpURLConnection conn = null;
    181             if(isproxy){//使用代理模式
    182                 @SuppressWarnings("static-access")
    183                 Proxy proxy = new Proxy(Proxy.Type.DIRECT.HTTP, new InetSocketAddress(proxyHost, proxyPort));
    184                 conn = (HttpURLConnection) realUrl.openConnection(proxy);
    185             }else{
    186                 conn = (HttpURLConnection) realUrl.openConnection();
    187             }
    188             // 打开和URL之间的连接
    189 
    190             // 发送POST请求必须设置如下两行
    191             conn.setDoOutput(true);
    192             conn.setDoInput(true);
    193             conn.setRequestMethod("POST");    // POST方法
    194 
    195 
    196             // 设置通用的请求属性
    197 
    198             conn.setRequestProperty("accept", "*/*");
    199             conn.setRequestProperty("connection", "Keep-Alive");
    200             conn.setRequestProperty("user-agent",
    201                     "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
    202             conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
    203 
    204             conn.connect();
    205 
    206             // 获取URLConnection对象对应的输出流
    207             out = new OutputStreamWriter(conn.getOutputStream(), "UTF-8");
    208             // 发送请求参数
    209             out.write(param);
    210             // flush输出流的缓冲
    211             out.flush();
    212             // 定义BufferedReader输入流来读取URL的响应
    213             in = new BufferedReader(
    214                     new InputStreamReader(conn.getInputStream()));
    215             String line;
    216             while ((line = in.readLine()) != null) {
    217                 result += line;
    218             }
    219         } catch (Exception e) {
    220             System.out.println("发送 POST 请求出现异常！"+e);
    221             e.printStackTrace();
    222         }
    223         //使用finally块来关闭输出流、输入流
    224         finally{
    225             try{
    226                 if(out!=null){
    227                     out.close();
    228                 }
    229                 if(in!=null){
    230                     in.close();
    231                 }
    232             }
    233             catch(IOException ex){
    234                 ex.printStackTrace();
    235             }
    236         }
    237         return result;
    238     }    
    239 
    240     public static void main(String[] args) {
    241         //demo:代理访问
    242         String url = "http://api.adf.ly/api.php";
    243         String para = "key=youkeyid&youuid=uid&advert_type=int&domain=adf.ly&url=http://somewebsite.com";
    244 
    245         String sr=HttpRequestUtil.sendPost(url,para,true);
    246         System.out.println(sr);
    247     }
    248 
    249 }

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**例3**

![复制代码][copycode.gif]

1 /**
     2      * 发送Http post请求
     3      * 
     4      * @param xmlInfo
     5      *            json转化成的字符串
     6      * @param URL
     7      *            请求url
     8      * @return 返回信息
     9      */
    10     public static String doHttpPost(String xmlInfo, String URL) {
    11         System.out.println("发起的数据:" + xmlInfo);
    12         byte[] xmlData = xmlInfo.getBytes();
    13         InputStream instr = null;
    14         java.io.ByteArrayOutputStream out = null;
    15         try {
    16             URL url = new URL(URL);
    17             URLConnection urlCon = url.openConnection();
    18             urlCon.setDoOutput(true);
    19             urlCon.setDoInput(true);
    20             urlCon.setUseCaches(false);
    21             urlCon.setRequestProperty("content-Type", "application/json");
    22             urlCon.setRequestProperty("charset", "utf-8");
    23             urlCon.setRequestProperty("Content-length",
    24                     String.valueOf(xmlData.length));
    25             System.out.println(String.valueOf(xmlData.length));
    26             DataOutputStream printout = new DataOutputStream(
    27                     urlCon.getOutputStream());
    28             printout.write(xmlData);
    29             printout.flush();
    30             printout.close();
    31             instr = urlCon.getInputStream();
    32             byte[] bis = IOUtils.toByteArray(instr);
    33             String ResponseString = new String(bis, "UTF-8");
    34             if ((ResponseString == null) || ("".equals(ResponseString.trim()))) {
    35                 System.out.println("返回空");
    36             }
    37             System.out.println("返回数据为:" + ResponseString);
    38             return ResponseString;
    39 
    40         } catch (Exception e) {
    41             e.printStackTrace();
    42             return "0";
    43         } finally {
    44             try {
    45                 out.close();
    46                 instr.close();
    47 
    48             } catch (Exception ex) {
    49                 return "0";
    50             }
    51         }
    52     }

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[copycode.gif]: /images/20220514/59dfaac02a794785918046014b47c5ab.png