java遍历目录-Java遍历文件夹-递归多线程实现最大速度遍历目录

启动方法（PS：调用这个方法就可以了）

	/**
	 * 获取某个目录下所有文件名,以文件夹分组
	 * 
	 * @param pathStr
	 * @return
	 */
	public static List<Map> getAllFilePathGroupFolder(String pathStr) {
		System.out.println("开始扫描："+ pathStr);
		Long nowTime = new Date().getTime();
		String str = pathStr;
		ScanFolderToFolderMap a = new ScanFolderToFolderMap(str);
		FutureTask<List<Map>> b = new FutureTask<List<Map>>(a);
		Thread worker = new Thread(b,str);
		worker.start();
		List<Map> c = null;
		try {
			c = b.get();
		} catch (Exception e) {
			e.printStackTrace();
			c = new ArrayList();
		}
		System.out.println("全部扫描结束,共扫描文件夹：" + c.size() + ",用时" + (new Date().getTime() - nowTime));
		return c;
	}
	

工具类（PS：直接粘贴就可以）

import java.io.File;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Callable;
import java.util.concurrent.FutureTask;

public class ScanFolderToFolderMap implements Callable<List<Map>>{
	
	//存储当前线程数量
	private static Integer sumJob = 0 ;
	
	private String folderPath = "";
	
	/**
	 * 初始化一个线程
	 * @param folderPath
	 */
	public ScanFolderToFolderMap(String folderPath){
		this.folderPath = folderPath;
	}
	
	
	/**
	 * 线程执行内容
	 */
	
	public List<Map> call() throws Exception {
		sumJob++;
		Long nowTime = new Date().getTime();

		
		//准备返回的路径
		List<Map> reArr = new ArrayList<Map>();
		
		//获取路径
		// 校验路径是否有问题
		try {
			File file = new File(folderPath);
			if ((!file.isDirectory()) && (!file.isFile())) {
				return null;
			}
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
		
		// 该目录下所有文件
		List<String> reFileArr = new ArrayList<String>();

		// 获取路径
		File file = new File(folderPath);

		// 获取文件夹内容以及判断是否有权限
		File[] sonFileArr = file.listFiles();
		if (sonFileArr == null){
			System.out.println("无权限");
			return null;
		}
		
		//准备子线程列表
		List<FutureTask<List<Map>>> workList = new ArrayList<FutureTask<List<Map>>>();
		
		//判断是否有子文件夹
		for(File fileObj:sonFileArr){
			if(fileObj.isFile()){
				//文件就添加路径
				reFileArr.add(fileObj.getAbsolutePath());
			}else{
				if(sumJob >= 10){
					try {
						//等带当前线程处理
						Thread.currentThread().sleep(sumJob*100);
					} catch (InterruptedException e) {
						e.printStackTrace();
					}
				}
				
				
				//文件夹就继续解析			
				ScanFolderToFolderMap a = new ScanFolderToFolderMap(fileObj.getAbsolutePath());
				FutureTask<List<Map>> b = new FutureTask<List<Map>>(a);
				workList.add(b);
				Thread worker = new Thread(b,fileObj.getAbsolutePath());
				worker.start();
			}
		}
		
		//获取所有线程返回信息
		for(FutureTask<List<Map>> workObj:workList){
			try {
				List<Map> mapArr = workObj.get();
				if (mapArr != null) {
					reArr.addAll(mapArr);
				}
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
		
		if (reFileArr.size() != 0) {
			Map fileMap = new HashMap();
			fileMap.put("folderName", file.getName());
			fileMap.put("folderPath", folderPath);
            Collections.sort(reFileArr);//对list集合进行排序
			fileMap.put("folderFiles", reFileArr);
			fileMap.put("date",file.lastModified());
			reArr.add(fileMap);
		}
		
		//返回扫描结果
		System.out.println((sumJob--) + ":扫描 " + folderPath + " 结束,用时" + (new Date().getTime() - nowTime));
		return reArr;
	}
	
}

本文地址：https://blog.csdn.net/weixin_42340354/article/details/109640118