今天，一个网友问了这个问题，下班后就动手写给他了，顺便记录下。哈哈，记得刚学Java那会儿写过这玩意。

package com.billstudy.demo;

import java.io.File;

/**
 * Folder recursion show 
 * @author Bill
 * @since V1.0 2015/01/22
 */
public class FileRecursion {
	public static void main(String[] args) {
		// source file direction 
		String sourceTargetFilePath = "E:/alibaba";
		
		File sourceTargetFile = new File(sourceTargetFilePath);
		
		System.out.println(sourceTargetFilePath);
		
		recursionFile(sourceTargetFile,0L);
		
	}

	/**
	 * recursion file 
	 * @param file
	 */
	private static void recursionFile(File file,long level) {
		if(file.isFile()){
			System.out.println(printFilePath(level) + file.getName());;
		}else{
			File[] files = file.listFiles();
			for (File innerFile : files) {
				System.out.println(printFilePath(level) + innerFile.getName());
				if(innerFile.isDirectory()){
					// continue recursion 
					level++;
					recursionFile(innerFile,level);
					level--;
				}
			}
		}
	}

	/**
	 * print file path by level 
	 * @param file
	 * @param level
	 */
	private static String printFilePath(long level) {
		StringBuilder tree = new StringBuilder("|--");
		for (int i = 0; i < level; i++)
			tree.append("|--");
		return tree.toString();
	}
}

 文件结构：

控制台输出：

遇到文件夹就深入，否则就打印结束递归。