java删除一个目录下面的所有文件

代码如下

import java.io.File;

public class DeleteAll{

 public static void deleteAll(File file){
 
   if(file.isFile() || file.list().length ==0)
   {
   file.delete();     
   }else{    
     File[] files = file.listFiles();
     for (int i = 0; i < files.length; i++) {
    deleteAll(files[i]);
    files[i].delete();    
   }

      
       if(file.exists())         //如果文件本身就是目录 ，就要删除目录
       file.delete();
   }
 }

 public static void main(String[] args){     
     File f = new File("f:"+File.separator+"test");
     deleteAll(f);
 }
}

请不要轻易测试！ 我的单元测试如下：

package com.jzm;

import java.io.File;

import junit.framework.Assert;

import junit.framework.TestCase;


public class DeleteAllTest extends TestCase{

	public void testDeleteAll(){   //如果是一个文件
		
		File file  = null;
		
		try{
		
		file = new File("f:\\test\\a.txt");
		
		file.createNewFile();	         
		
		DeleteAll.deleteAll(file);
		
		}catch (Exception e) {
			// TODO: handle exception
		}	
		Assert.assertFalse(file.exists());		
	}
	
	
	public void testDeleteAll2(){         //如果是一个一级目录
			
			File directory  = null;
			
			try{
						
			directory  = new File("f:"+ File.separator +"dirT2");
			 
		    directory.mkdir();
			
			File file1 = new File(directory, "t1.txt");
			
			File file2 = new File(directory, "t2.txt");
			
			file1.createNewFile();
			
			file2.createNewFile();			
			
			DeleteAll.deleteAll(directory);		
			
			}catch (Exception e) {
				
				// TODO: handle exception				
			}					
			Assert.assertFalse(directory.exists());		
		}
	
	public void testDeleteAll3(){          //如果是一个二级目录
		
		File directory  = null;
		
		try{
					
		directory  = new File("f:"+ File.separator +"dirT3");
		 
	    directory.mkdir();
	    
	    File  dir1  = new File(directory,"dir1");
	    dir1.mkdir();
	    
	    File  dir2  = new File(directory,"dir2");
	    dir2.mkdir();
	    
		
		File file1 = new File(dir1, "t1.txt");
		
		File file2 = new File(dir2, "t2.txt");
		
		file1.createNewFile();
		
		file2.createNewFile();			
		
		DeleteAll.deleteAll(directory);		
		
		}catch (Exception e) {
			
			// TODO: handle exception				
		}			
		Assert.assertFalse(directory.exists());		
	}

	
}