最近在用到了HttpClient發送post和get請求三方接口的需求，是以寫了個封裝類友善以後用到：
需要用到的一些jar的maven坐标：
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.5</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.7</version>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.11</version>
</dependency>
<dependency>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
<version>1.2</version>
</dependency>
HttpUtil封裝類：
package com.springboot.demo.test.service;
import com.alibaba.fastjson.JSON;
import org.apache.commons.lang3.StringUtils;
import org.apache.http.*;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
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.client.methods.HttpUriRequest;
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.protocol.BasicHttpContext;
import org.apache.http.protocol.HttpContext;
import org.apache.http.protocol.HttpCoreContext;
import org.apache.http.util.EntityUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.CollectionUtils;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.message.BasicNameValuePair;
import java.io.*;
import java.util.*;
public class HttpUtil {
private static final Logger logger = LoggerFactory.getLogger(HttpUtil.class);
private static RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(60000).setConnectTimeout(60000).build();
private static String chaset = "UTF-8"; // 預設編碼
/**
* 發送 GET 請求（HTTP），無參數
* @param url
* @return
*/
public static String doGet(String url) {
if (StringUtils.isBlank(url)) {
return "url不能為空";
}
// 建立http GET請求
logger.info("url:{}", url);
HttpGet httpGet = new HttpGet(url);
// 設定請求和傳輸逾時時間
httpGet.setConfig(requestConfig);
String result = "";
try (CloseableHttpClient httpclient = HttpClients.createDefault();// 建立Httpclient對象
CloseableHttpResponse response = httpclient.execute(httpGet);// 執行請求
) {
int statusCode = response.getStatusLine().getStatusCode();
if (statusCode == HttpStatus.SC_OK) {
result = EntityUtils.toString(response.getEntity(), chaset);
logger.info("HttpGet方式請求成功！傳回結果：{}", result);
} else {
logger.info("HttpGet方式請求失敗！狀态碼:" + statusCode);
}
} catch (IOException e) {
e.printStackTrace();
}
return result;
}
/**
* 發送 GET 請求（HTTP），有參數
* @param url
* @param params
* @return
*/
public static String doGet(String url, Map<String, Object> params) {
if (!CollectionUtils.isEmpty(params)) {
StringBuffer extraUrl = new StringBuffer();
int temp = 0;
for (String key : params.keySet()) {
if (temp == 0) {
extraUrl.append("?");
} else {
extraUrl.append("&");
}
extraUrl.append(key).append("=").append(params.get(key));
temp++;
}
url += extraUrl;
}
return doGet(url);
}
/**
* 發送 GET 請求（HTTP），擷取跳轉的最終url連結傳回
*
* @param url
* @return
*/
public static String doGetJumpLink(String url) {
if (StringUtils.isBlank(url)) {
return "url不能為空";
}
// 建立http GET請求
HttpGet httpGet = new HttpGet(url);
HttpContext context = new BasicHttpContext();
String currentUrl ="";
try (CloseableHttpClient httpclient = HttpClients.createDefault();// 建立Httpclient對象
CloseableHttpResponse response = httpclient.execute(httpGet,context);// 執行請求
) {
int statusCode = response.getStatusLine().getStatusCode();
if (statusCode != HttpStatus.SC_OK) {
return currentUrl="HttpGet方式請求失敗！狀态碼:" + statusCode;
}
//logger.info("HttpGet方式請求成功！傳回結果：{}", result);
HttpUriRequest currentReq = (HttpUriRequest) context.getAttribute(
HttpCoreContext.HTTP_REQUEST);
HttpHost currentHost = (HttpHost) context.getAttribute(
HttpCoreContext.HTTP_TARGET_HOST);
currentUrl = (currentReq.getURI().isAbsolute()) ? currentReq.getURI().toString() : (currentHost.toURI() + currentReq.getURI());
} catch (IOException e) {
e.printStackTrace();
}
return currentUrl;
}
/**
* 發送 POST 請求（HTTP），無參數
* @param url
* @return
*/
public static String doPost(String url) {
return doPost(url, null);
}
/**
* 發送 POST 請求（HTTP），有參數
* @param url
* @return
*/
public static String doPost(String url, Map<String, Object> params) {
// 建立http POST請求
HttpPost httpPost = new HttpPost(url);
httpPost.setConfig(requestConfig);
httpPost.setHeader("Content-Type", "application/json");
if (params != null) {
httpPost.setEntity(new StringEntity(JSON.toJSONString(params), ContentType.create("application/json", "utf-8")));
}
String result = "";
try (CloseableHttpClient httpclient = HttpClients.createDefault();// 建立Httpclient對象
CloseableHttpResponse response = httpclient.execute(httpPost);// 執行請求
) {
logger.info("httpPost:{}", httpPost);
int statusCode = response.getStatusLine().getStatusCode();
if (statusCode == HttpStatus.SC_OK) {
result = EntityUtils.toString(response.getEntity(), chaset);
logger.info("HttpPost方式請求成功！傳回結果：{}", result);
} else {
logger.info("HttpPost方式請求失敗！狀态碼:" + statusCode);
}
} catch (IOException e) {
e.printStackTrace();
}
return result;
}
public static String doPost1(String url, Map<String, Object> paramMap) {
CloseableHttpClient httpClient = null;
CloseableHttpResponse httpResponse = null;
String result = "";
// 建立httpClient執行個體
httpClient = HttpClients.createDefault();
// 建立httpPost遠端連接配接執行個體
HttpPost httpPost = new HttpPost(url);
// 配置請求參數執行個體
RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(5000)// 設定連接配接主機服務逾時時間
.setConnectionRequestTimeout(5000)// 設定連接配接請求逾時時間
.setSocketTimeout(5000)// 設定讀取資料連接配接逾時時間
.build();
// 為httpPost執行個體設定配置
httpPost.setConfig(requestConfig);
// 設定請求頭
httpPost.addHeader("Content-Type", "application/x-www-form-urlencoded");
// 封裝post請求參數
if (null != paramMap && paramMap.size() > 0) {
List<NameValuePair> nvps = new ArrayList<NameValuePair>();
// 通過map內建entrySet方法擷取entity
Set<Map.Entry<String, Object>> entrySet = paramMap.entrySet();
// 循環周遊，擷取疊代器
Iterator<Map.Entry<String, Object>> iterator = entrySet.iterator();
while (iterator.hasNext()) {
Map.Entry<String, Object> mapEntry = iterator.next();
nvps.add(new BasicNameValuePair(mapEntry.getKey(), mapEntry.getValue().toString()));
}
// 為httpPost設定封裝好的請求參數
try {
httpPost.setEntity(new UrlEncodedFormEntity(nvps, "UTF-8"));
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
try {
// httpClient對象執行post請求,并傳回響應參數對象
httpResponse = httpClient.execute(httpPost);
// 從響應對象中擷取響應内容
HttpEntity entity = httpResponse.getEntity();
result = EntityUtils.toString(entity);
} catch (ClientProtocolException e) {
logger.error("錯誤資訊: ", e);
} catch (IOException e) {
logger.error("錯誤資訊: ", e);
} finally {
// 關閉資源
if (null != httpResponse) {
try {
httpResponse.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (null != httpClient) {
try {
httpClient.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return result;
}
/**
* 發送 POST 請求（HTTP），有參數和cookie
*
* @param url
* @param params 參數
* @param cookie 例如：LBSESSION=NGEzODUyNjUtYjZkYy00ZmNkLWJhZTAtMDBmYWNjYzQzZjBi
* @return
*/
public static String doPost(String url, Map<String, Object> params, String cookie) {
// 建立http POST請求
HttpPost httpPost = new HttpPost(url);
httpPost.setConfig(requestConfig);
httpPost.setHeader("Content-Type", "application/json");
if (params != null) {
httpPost.setEntity(new StringEntity(JSON.toJSONString(params), ContentType.create("application/json", "utf-8")));
}
if (cookie != null) {
httpPost.addHeader("Cookie", cookie);
}
String result = "";
try (CloseableHttpClient httpclient = HttpClients.createDefault();// 建立Httpclient對象
CloseableHttpResponse response = httpclient.execute(httpPost);// 執行請求
) {
logger.info("httpPost:{}", httpPost);
int statusCode = response.getStatusLine().getStatusCode();
if (statusCode == HttpStatus.SC_OK) {
result = EntityUtils.toString(response.getEntity(), chaset);
logger.info("HttpPost方式請求成功！傳回結果：{}", result);
} else {
logger.info("HttpPost方式請求失敗！狀态碼:" + statusCode);
}
} catch (IOException e) {
e.printStackTrace();
}
return result;
}
/**
* 通過url下載下傳視訊
*
* @param url
* @return
*/
public static String downVideo(String url) {
//預設下載下傳到D:\video\
return downVideo(url, "D:\\video\\");
}
/**
* 通過url下載下傳視訊
*
* @param url
* @param filepath 下載下傳到本地的路徑
* @return
*/
public static String downVideo(String url, String filepath) {
String filename="";
try {
//擷取視訊流
HttpClient client = HttpClients.createDefault();
HttpGet httpget = new HttpGet(url);
HttpResponse response = client.execute(httpget);
HttpEntity entity = response.getEntity();
InputStream is = entity.getContent();
//filepath不是斜杠結束的在末尾添加斜杠
if (filepath.length()-1!=filepath.lastIndexOf("\\")){
filepath+="\\";
}
//如果沒有檔案夾，則建立
File file = new File(filepath);
if (!file.exists() && !file.isDirectory()) {
file.mkdirs();
}
//擷取檔案夾下的檔案數量，檔案數量加一作為要下載下傳的檔案名
int fileCount = 0;
File[] list = file.listFiles();
for (int i = 0; i < list.length; i++) {
if (list[i].isFile()) {
fileCount++;
}
}
fileCount += 1;
//如果檔案不存在則建立檔案
filename = filepath + fileCount + ".mp4";
File file_name = new File(filename);
if (!file_name.exists()) {
//建立檔案
file_name.createNewFile();
}
//視訊流寫入檔案
FileOutputStream fileout = new FileOutputStream(file_name);
BufferedInputStream buf = new BufferedInputStream(is);
byte[] buffer = new byte[1024];
int ch = 0;
while ((ch = buf.read(buffer)) != -1) {
fileout.write(buffer, 0, ch);
}
is.close();
fileout.flush();
fileout.close();
} catch (Exception e) {
e.printStackTrace();
}
return "下載下傳成功，檔案名："+filename;
}
}
用的時候直接調用就行，如：
Map<String, Object> map = new HashMap<>();
map.put("a", additionModel.getA());
map.put("b", additionModel.getB());
String result = HttpUtil.doGet("http://125.113.27.170:8080/query/v1/addition",map);
參考：
HttpClient 4 - how to capture last redirect URL
使用httpclient獲得伺服器跳轉之後的url！
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