一个Java实现的有道云笔记中包含的图片文件的批量下载工具

package youdao;

import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.net.URL;
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 com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.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;

class ImageDownloader implements Runnable {
	private String mUrl = null;
	private int index = -1;
	private String parent = null;

	public ImageDownloader(String parent, String url, int index){
		this.mUrl = url;
		this.index = index;
		this.parent = parent;
	}
	
	@Override
	public void run() {
		URL url = null;
		
        try {
            url = new URL(this.mUrl);
            DataInputStream dataInputStream = new DataInputStream(url.openStream());

            String imageName =  parent +
            		"/clipboard" + ++this.index + ".png";

            FileOutputStream fileOutputStream = new FileOutputStream(new File(imageName));
            ByteArrayOutputStream output = new ByteArrayOutputStream();

            byte[] buffer = new byte[1024];
            int length;

            while ((length = dataInputStream.read(buffer)) > 0) {
                output.write(buffer, 0, length);
            }

            fileOutputStream.write(output.toByteArray());
            dataInputStream.close();
            fileOutputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
	}
}

public class YoudaoNoteBatch {

	private static String SHAREID = "a9d31900bb8d0b89ce7b15fa30d1f0d3";
	private static String FOLDERURL = "https://note.youdao.com/yws/public/notebook/";
	private static String NOTEURL = "https://note.youdao.com/yws/public/note/";
	private static String RESULTFOLDER = "C:/Users/i042416/Pictures/wiki/";
		
	private static void createFolder(String title){
		File file = new File(title);
		file.mkdir();
	}
	
	private static List<String> getImageURLArray(JSONObject note){
		String[] uniqueIDs = note.getString("p").split("/");
		String uniqueID = uniqueIDs[2];
		String noteurl = NOTEURL + SHAREID + "/" + uniqueID;
		HttpClient client = HttpClients.createDefault();
		
	    HttpGet get = new HttpGet(noteurl);
	    String result = null;
	    List<String> imageList = new ArrayList<String>();
	        try {
	            HttpResponse response = client.execute(get);
	            HttpEntity entity = response.getEntity();
	            result = EntityUtils.toString(entity, "UTF-8");
	            JSONObject noteDetail = (JSONObject)JSON.parse(result);
	            String content = noteDetail.getString("content");
	            String img = null;
	            Pattern p_image;
	            Matcher m_image;
	            String regEx_img = "<img.*src\\s*=\\s*(.*?)[^>]*?>";
	            p_image = Pattern.compile(regEx_img, Pattern.CASE_INSENSITIVE);
	            m_image = p_image.matcher(content);
	            while (m_image.find()) {
	                img = m_image.group();
	                Matcher m = Pattern.compile("src\\s*=\\s*\"?(.*?)(\"|>|\\s+)").matcher(img);
	                while (m.find()) {
	                	String image = m.group(1);
	                	//System.out.println("image to be downloaded: " + image);
	                	
	                	// Jerry: why this can happen??
	                	if( image.contains("https://wiki.jerry.sap.corp/wiki/")){
	                		imageList.clear();
	                		System.out.println("content: " + content);
	                		return imageList;
	                	}
	                	imageList.add(m.group(1));
	                }
	            }
	        }
	        catch(Exception e){
	        	e.printStackTrace();
	        	System.exit(-1);
	        }
	        return imageList;
	}
	
	private static void start(List<String> images, String parent, String title){
		System.out.println("note image size : " + images.size() + " note: " + title );
		ExecutorService executor = Executors.newFixedThreadPool(10);
		
		for( int i = 0; i < images.size(); i++){
			ImageDownloader cc = new ImageDownloader(parent, images.get(i), i);
			executor.execute(cc);			
		}
		
		executor.shutdown();
		while (!executor.isTerminated()) {
        }
		
		System.out.println("download finished for note: " + parent);
	}
	
	private static void download(JSONObject note){
		List<String> images = getImageURLArray(note);
		if( images.isEmpty()){
			System.err.println("note: " + note.getString("tl") + " image corrupted. Please retry.");
			return;
		}
		String name = note.getString("tl");
		String remove_note = name.substring(0, name.length() - 5);
		String parent = RESULTFOLDER + remove_note;
		
		createFolder(parent);
		start(images, parent, remove_note);
	}
	private static void getPictureList(){
		String entry = FOLDERURL + SHAREID;
		HttpClient client = HttpClients.createDefault();
		
	    HttpGet get = new HttpGet(entry);
	    String result = null;
	        try {
	            HttpResponse response = client.execute(get);
	            HttpEntity entity = response.getEntity();
	            result = EntityUtils.toString(entity, "UTF-8");
	    	    JSONArray aResult = (JSONArray) JSON.parse(result);
	    	    int totalCount = (int) aResult.get(0);
	    	    JSONArray aNoteList = (JSONArray)aResult.get(2);
	    	    System.out.println("Total note: " + totalCount);
	    	    for( int i = 0; i < totalCount; i++){
	    	    	JSONObject note = (JSONObject) aNoteList.get(i);
	    	    	download(note);
	    	    }
	        }
	        catch(Exception e){
	        	e.printStackTrace();
	        	System.exit(-1);
	        }
	}
	public static void main(String[] args) {
		getPictureList();
		System.out.println("*********************** DONE !!! *************************");
	}
}