一个基于Java实现的Github issue图片自动下载工具

package youdao;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.json.JSONObject;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
public class Github {
  private static String mTitle = null;
  private static final String PREFIX = "C:\\Users\\i042416\\Pictures\\";
  private static void createFolder(String title){
    DownloadTask.FOLDER = PREFIX + title;
    File file = new File( DownloadTask.FOLDER);
    file.mkdir();
  }
  private static List<DownloadTask> getGithubPicUrlList(String formattedUrl){
    HttpClient client = HttpClients.createDefault();
    List<DownloadTask> resultPic = new ArrayList<DownloadTask>();
    int index = 0;
      HttpGet get = new HttpGet(formattedUrl);
          try {
              HttpResponse response = client.execute(get);
              HttpEntity entity = response.getEntity();
              String result = EntityUtils.toString(entity, "UTF-8");
              JSONObject obj = new JSONObject(result);
              mTitle = obj.get("tl").toString();
              createFolder(mTitle);
              String content = obj.get("content").toString();
              // System.out.println("content: " + content);
              Matcher m = Pattern.compile("src\\s*=\\s*\"?(.*?)(\"|>|\\s+)").matcher(content);
              while (m.find()) {
                      // System.out.println(m.group(1));
                      DownloadTask task = new DownloadTask(m.group(1), index++);
                      resultPic.add(task);
              }
          } catch (Exception e){
            e.printStackTrace();
          }
          return resultPic;
  }
  private static List<DownloadTask> getGithubIssuePicUrlList(String githubIssueUrl){
    HttpClient client = HttpClients.createDefault();
    List<DownloadTask> resultPic = new ArrayList<DownloadTask>();
    int index = 0;
      HttpGet get = new HttpGet(githubIssueUrl);
          try {
              HttpResponse response = client.execute(get);
              HttpEntity entity = response.getEntity();
              String result = EntityUtils.toString(entity, "UTF-8");
              JSONObject obj = new JSONObject(result);
              mTitle = obj.get("title").toString();
              createFolder(mTitle);
              String content = obj.get("body").toString();
              System.out.println("content: " + content);
              // ![clipboard2](https://user-int.com/5669954/32708736946.png)
              // Matcher m = Pattern.compile("^\\d{n,}$").matcher(content);
              Matcher m = Pattern.compile(".*!\\[.*?\\]\\(.*?\\).*").matcher(content);
              while (m.find()) {
                      // System.out.println(m.group(1));
                      DownloadTask task = new DownloadTask(m.group(1), index++);
                      resultPic.add(task);
              }
          } catch (Exception e){
            e.printStackTrace();
          }
          return resultPic;
  }
  private static void start(List<DownloadTask> task){
    if( task.isEmpty()){
      System.out.println("No picture to download!");
      return;
    }
    System.out.println("Total pic to be downloaded: " + task.size());
    ExecutorService executor = Executors.newFixedThreadPool(10);
    for( int i = 0; i < task.size(); i++){
      PictureDownloader cc = new PictureDownloader(task.get(i));
      executor.execute(cc);     
    }
    executor.shutdown();
    while (!executor.isTerminated()) {
        }
    System.out.println("download finished");
  }
  public static void main(String[] args) {
    /*String urlStr = "https://api.github.com/repos/i042416/KnowlegeRepository/issues/955";
    System.out.println(urlStr);
    List<DownloadTask> task = getGithubIssuePicUrlList(urlStr);
    start(task);*/
    String a = "![clipboard1](https://user-images.githubusercontent.com/5669954/32708735-bc205af6-c866-11e7-8314-cdcd2b33f050.png) fuck";
    a = a + "\n" + "![clipboard2](https://user-images.githubusercontent.com/5669954/32708736-bc54ae78-c866-11e7-9ab8-40b2fde6c946.png)";
    Matcher m = Pattern.compile(".*\\!\\[.*\\]\\((.*)\\).*").matcher(a);
        while (m.find()) {
            int group_code = m.groupCount();
            System.out.println("group count: " + group_code);
                System.out.println("image: " + m.group(1));
        }
  }
}