1. org.apache.commons.httpclient.HttpClient

package com.skd.util;

import com.skd.common.Constant;
import com.skd.common.Event;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.commons.httpclient.methods.multipart.FilePart;
 
import org.apache.commons.httpclient.methods.multipart.MultipartRequestEntity;
import org.apache.commons.httpclient.methods.multipart.Part;
import org.apache.commons.httpclient.methods.multipart.StringPart;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.util.ArrayList;
 
import java.util.List;

/**
 * @Description
 * @Author virgosnail
 * @Date 2018/12/15 17:06
 */
public class HttpUtil2
{
    private static Logger log = LoggerFactory.getLogger(HttpUtil2.class);
    /**
     * org.apache.commons.httpclient.HttpClient
      */
    private static HttpClient httpClient = new
 
 HttpClient();

    /**
     * @param event  0:刪除  1：新增  2：修改
     * @param file
     * @return
    
     * @Author Administrator
     * @Date 2018年11月11日
     */
    public static void doPostMethod(Event event, File file)
    {
        try
        {
            PostMethod post = new PostMethod(FileUtil.getURL());
            post.setRequestHeader("Content-Type","application/json");
            List<Part> list = new ArrayList<>();
            list.add(new StringPart(Constant.TYPE, event.getValue()));
            list.add(new StringPart(Constant.RELATIVE_PATH, file.getPath()));
            
            if (!Event.FILE_DELETE.equals(event))
            {
　　　　　　　　　　// 
                list.add(new FilePart(Constant.FILE, file));
            }
            Part[] parts = new Part[list.size()];
            list.toArray();
            post.setRequestEntity(new MultipartRequestEntity(parts, post.getParams()));
            
            log.info("request： " + post);
            
            httpClient.executeMethod(post);
            String response = post.getResponseBodyAsString();
            log.info("respopnse: " + response);
        } catch (Exception e)
        {
            log.error("doPostMethod occur a exception", e);
        }
    }

}

2. org.apache.http.client.HttpClient

package com.skd.util;

import com.skd.common.Constant;
import com.skd.common.Event;
import net.sf.json.JSONObject;
import org.apache.http.Header;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.nio.charset.Charset;

/**
 * @Description
 * @Author virgosnail
 * @Date 2018/12/15 17:06
 */
public class HttpUtil
{
    private static Logger log = LoggerFactory.getLogger(HttpUtil.class);
    /**
     *     org.apache.http.client.HttpClient;
     *     創建一個httpclient對象
      */
    private static HttpClient httpclient = HttpClients.createDefault();
    
    /**
     * @param event  0:刪除  1：新增  2：修改
     * @param file
     * @return
    
     * @Author Administrator
     * @Date 2018年11月11日
     */
    public static void doPost(Event event, File file, boolean isDir, boolean hasFile)
    {
        try
        {
            // 創建http的發送方式對象，是GET還是POST
            String url = FileUtil.getURL();
            HttpPost httppost = new HttpPost(url);
            log.info(" URL: " + url);
            httppost.addHeader("Charset",Constant.CHARSET);
            // 創建要發送的實體，就是key-value的這種結構，借助於這個類，可以實現文件和參數同時上傳
            MultipartEntityBuilder fileEntity = MultipartEntityBuilder.create();
            // 設置編碼
            Charset charset = Charset.forName(Constant.CHARSET);
            fileEntity.setCharset(charset);
            // 追加要發送的文本信息並設置編碼格式
            fileEntity.addTextBody(Constant.TYPE, event.getValue(),ContentType.APPLICATION_JSON);
            log.info("type： " + event.getValue());
            String relativePath = FileUtil.getRelativePath(file.getAbsolutePath());
            fileEntity.addTextBody(Constant.RELATIVE_PATH, relativePath,ContentType.APPLICATION_JSON);
            log.info("relative_path： " + relativePath);
            fileEntity.addTextBody(Constant.ISDIR, String.valueOf(isDir),ContentType.APPLICATION_JSON);
            log.info("isDir： " + isDir);
            if (Event.FILE_CREATE.equals(event) || Event.FILE_CHANGE.equals(event)){
                fileEntity.addPart(Constant.FILE, new FileBody(file,ContentType.APPLICATION_OCTET_STREAM));
            }
            log.info("file： " + file);
            HttpEntity httpEntity = fileEntity.build();
            httppost.setEntity(httpEntity);
            // 執行httppost對象並獲得response
            HttpResponse response = httpclient.execute(httppost);
            // 狀態碼
            int statusCode = response.getStatusLine().getStatusCode();
            HttpEntity resEntity = response.getEntity();
            // 獲得返回來的信息，轉化為字符串string
            String respopnse = EntityUtils.toString(resEntity);
            log.info("respopnse body: " + respopnse);
        } catch (Exception e)
        {
            log.error("doPost occur a exception", e);
        }
    }
}

HttpClient 傳輸文件的兩種方式