public Class Test{

    //定义全局变量，存放所有文件夹下的文档

    List<String> fileList ;

    public List<String> getFileLists() {

        String path = "路径";

        //用的时候再new，相当于用之前清空一下List

        fileList = new ArrayList<String>();

        List<String> list = getFileListsByPath(path);

        return list;

    }

    public List<String> getFileListsByPath(String path) {

        File file = new File(path);

        if(file.exists()){

            File[] files = file.listFiles();

            for(File file2 : files){

                //若是文件夹，递归调用，往下继续遍历

                if(file2.isDirectory()){

                    //遍历子文件夹的绝对路径下的所有文件

                    getFileListsByPath(file2.getAbsolutePath());

                }else{

                    //若是文档，非文件夹，加入List

                    fileList.add(file2.getAbsolutePath());

                }

            }

        }

        return fileList;

    }

}

/*

 * 删除指定文件夹及里面所有文件

 */

import java.io.File;

public class RemoveDirectoryUtil {

    //获得绝对路径：/D:/eclipse/workspace/项目名称/WebContent/WEB-INF/classes/

    public final static String HOME_PATH = RemoveDirectoryUtil.class.getResource("/").getPath();

    //获得绝对路径：/D:/eclipse/workspace/项目名称/WebContent/下的其他目录

    public final static String FILE_PATH = HOME_PATH.subSequence(, HOME_PATH.indexOf("WEB-INF")) + "file/";

    //删除文件夹

    //param folderPath 文件夹完整绝对路径

    public static void delFolder(String folderPath) {

         try {

             delAllFile(folderPath); //删除完里面所有内容

             String filePath = folderPath;

             filePath = filePath.toString();

             java.io.File myFilePath = new java.io.File(filePath);

             myFilePath.delete(); //删除空文件夹

         } catch (Exception e) {

             e.printStackTrace();

         }

    }

    //删除指定文件夹下所有文件

    //param path 文件夹完整绝对路径

       public static boolean delAllFile(String path) {

           boolean flag = false;

           File file = new File(path);

           if (!file.exists()) {

             return flag;

           }

           if (!file.isDirectory()) {

             return flag;

           }

           String[] tempList = file.list();

           File temp = null;

           for (int i = ; i < tempList.length; i++) {

              if (path.endsWith(File.separator)) {

                 temp = new File(path + tempList[i]);

              } else {

                  temp = new File(path + File.separator + tempList[i]);

              }

              if (temp.isFile()) {

                 temp.delete();

              }

              if (temp.isDirectory()) {

                 delAllFile(path + "/" + tempList[i]);//先删除文件夹里面的文件

                 delFolder(path + "/" + tempList[i]);//再删除空文件夹

                 flag = true;

              }

           }

           return flag;

         }

}

RemoveDirectoryUtil.FILE_PATH

RemoveDirectoryUtil.delFolder("你的文件夹所在路径");