Java 发送http请求上传文件功能实例

废话不多说了，直接给大家贴代码了，具体代码如下所示：

package wxapi.WxHelper;
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.util.Date;
import java.util.Map;
import java.util.Map.Entry;
public class HttpRequestUtil {
  /**
   * 发送get请求
   *
   * @param requestUrl
   *      请求url
   * @param requestHeader
   *      请求头
   * @param responseEncoding
   *      响应编码
   * @return 页面响应html
   */
  public static String sendGet(String requestUrl, Map<String, String> requestHeader, String responseEncoding) {
    String result = "";
    BufferedReader reader = null;
    try {
      if (requestUrl == null || requestUrl.isEmpty()) {
        return result;
      }
      URL realUrl = new URL(requestUrl);
      URLConnection connection = realUrl.openConnection();
      connection.setRequestProperty("accept", "text/html, application/xhtml+xml, image/jxr, */*");
      connection.setRequestProperty("user-agent", "Mozilla/5.0 (Windows NT 10.0; WOW64; rv:53.0) Gecko/20100101 Firefox/53.0");
      if (requestHeader != null && requestHeader.size() > 0) {
        for (Entry<String, String> entry : requestHeader.entrySet()) {
          connection.setRequestProperty(entry.getKey(), entry.getValue());
        }
      }
      connection.connect();
      if (responseEncoding == null || responseEncoding.isEmpty()) {
        responseEncoding = "UTF-8";
      }
      reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), responseEncoding));
      String line;
      while ((line = reader.readLine()) != null) {
        result += line;
      }
    } catch (Exception e) {
      System.out.println("发送GET请求出现异常！");
      e.printStackTrace();
    } finally {
      try {
        if (reader != null) {
          reader.close();
        }
      } catch (Exception e) {
        e.printStackTrace();
      }
    }
    return result;
  }
  /**
   * 发送post请求
   *
   * @param requestUrl
   *      请求url
   * @param requestHeader
   *      请求头
   * @param formTexts
   *      表单数据
   * @param files
   *      上传文件
   * @param requestEncoding
   *      请求编码
   * @param responseEncoding
   *      响应编码
   * @return 页面响应html
   */
  public static String sendPost(String requestUrl, Map<String, String> requestHeader, Map<String, String> formTexts, Map<String, String> files, String requestEncoding, String responseEncoding) {
    OutputStream out = null;
    BufferedReader reader = null;
    String result = "";
    try {
      if (requestUrl == null || requestUrl.isEmpty()) {
        return result;
      }
      URL realUrl = new URL(requestUrl);
      HttpURLConnection connection = (HttpURLConnection) realUrl.openConnection();
      connection.setRequestProperty("accept", "text/html, application/xhtml+xml, image/jxr, */*");
      connection.setRequestProperty("user-agent", "Mozilla/5.0 (Windows NT 10.0; WOW64; rv:53.0) Gecko/20100101 Firefox/53.0");
      if (requestHeader != null && requestHeader.size() > 0) {
        for (Entry<String, String> entry : requestHeader.entrySet()) {
          connection.setRequestProperty(entry.getKey(), entry.getValue());
        }
      }
      connection.setDoOutput(true);
      connection.setDoInput(true);
      connection.setRequestMethod("POST");
      if (requestEncoding == null || requestEncoding.isEmpty()) {
        requestEncoding = "UTF-8";
      }
      if (responseEncoding == null || responseEncoding.isEmpty()) {
        responseEncoding = "UTF-8";
      }
      if (requestHeader != null && requestHeader.size() > 0) {
        for (Entry<String, String> entry : requestHeader.entrySet()) {
          connection.setRequestProperty(entry.getKey(), entry.getValue());
        }
      }
      if (files == null || files.size() == 0) {
        connection.setRequestProperty("content-type", "application/x-www-form-urlencoded");
        out = new DataOutputStream(connection.getOutputStream());
        if (formTexts != null && formTexts.size() > 0) {
          String formData = "";
          for (Entry<String, String> entry : formTexts.entrySet()) {
            formData += entry.getKey() + "=" + entry.getValue() + "&";
          }
          formData = formData.substring(0, formData.length() - 1);
          out.write(formData.toString().getBytes(requestEncoding));
        }
      } else {
        String boundary = "-----------------------------" + String.valueOf(new Date().getTime());
        connection.setRequestProperty("content-type", "multipart/form-data; boundary=" + boundary);
        out = new DataOutputStream(connection.getOutputStream());
        if (formTexts != null && formTexts.size() > 0) {
          StringBuilder sbFormData = new StringBuilder();
          for (Entry<String, String> entry : formTexts.entrySet()) {
            sbFormData.append("--" + boundary + "\r\n");
            sbFormData.append("Content-Disposition: form-data; name=\"" + entry.getKey() + "\"\r\n\r\n");
            sbFormData.append(entry.getValue() + "\r\n");
          }
          out.write(sbFormData.toString().getBytes(requestEncoding));
        }
        for (Entry<String, String> entry : files.entrySet()) {
          String fileName = entry.getKey();
          String filePath = entry.getValue();
          if (fileName == null || fileName.isEmpty() || filePath == null || filePath.isEmpty()) {
            continue;
          }
          File file = new File(filePath);
          if (!file.exists()) {
            continue;
          }
          out.write(("--" + boundary + "\r\n").getBytes(requestEncoding));
          out.write(("Content-Disposition: form-data; name=\"" + fileName + "\"; filename=\"" + file.getName() + "\"\r\n").getBytes(requestEncoding));
          out.write(("Content-Type: application/x-msdownload\r\n\r\n").getBytes(requestEncoding));
          DataInputStream in = new DataInputStream(new FileInputStream(file));
          int bytes = 0;
          byte[] bufferOut = new byte[1024];
          while ((bytes = in.read(bufferOut)) != -1) {
            out.write(bufferOut, 0, bytes);
          }
          in.close();
          out.write(("\r\n").getBytes(requestEncoding));
        }
        out.write(("--" + boundary + "--").getBytes(requestEncoding));
      }
      out.flush();
      out.close();
      out = null;
      reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), responseEncoding));
      String line;
      while ((line = reader.readLine()) != null) {
        result += line;
      }
    } catch (Exception e) {
      System.out.println("发送POST请求出现异常！");
      e.printStackTrace();
    } finally {
      try {
        if (out != null) {
          out.close();
        }
        if (reader != null) {
          reader.close();
        }
      } catch (IOException ex) {
        ex.printStackTrace();
      }
    }
    return result;
  }
} 

以上所述是小编给大家介绍的Java 发送http请求上传文件功能实例，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对我们网站的支持！