import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
public class BackUp {
 /** 
     * 复制单个文件 
     * @param oldPath String 原文件路径 如：c:/fqf.txt 
     * @param newPath String 复制后路径 如：f:/fqf.txt 
     * @return boolean 
     */ 
   public void copyFile(String oldPath, String newPath) { 
       try { 
           int bytesum = 0; 
           int byteread = 0; 
           File oldfile = new File(oldPath); 
           if (oldfile.exists()) { //文件存在时 
               InputStream inStream = new FileInputStream(oldPath); //读入原文件 
               FileOutputStream fs = new FileOutputStream(newPath); 
               byte[] buffer = new byte[1444]; 
               int length; 
               while ( (byteread = inStream.read(buffer)) != -1) { 
                   bytesum += byteread; //字节数 文件大小 
                   System.out.println(bytesum); 
                   fs.write(buffer, 0, byteread); 
               } 
               inStream.close(); 
           } 
       } 
       catch (Exception e) { 
           System.out.println("复制单个文件操作出错"); 
           e.printStackTrace(); 
       } 
   } 
   /** 
     * 复制整个文件夹内容 
     * @param oldPath String 原文件路径 如：c:/fqf 
     * @param newPath String 复制后路径 如：f:/fqf/ff 
     * @return boolean 
     */ 
   public void copyFolder(String oldPath, String newPath) { 
       try { 
           (new File(newPath)).mkdirs(); //如果文件夹不存在 则建立新文件夹 
           File a=new File(oldPath); 
           String[] file=a.list(); 
           File temp=null; 
           for (int i = 0; i < file.length; i++) { 
               if(oldPath.endsWith(File.separator)){ 
                   temp=new File(oldPath+file[i]); 
               } 
               else{ 
                   temp=new File(oldPath+File.separator+file[i]); 
               } 
               if(temp.isFile()){ 
                   FileInputStream input = new FileInputStream(temp); 
                   FileOutputStream output = new FileOutputStream(newPath + "/" + 
                           (temp.getName()).toString()); 
                   byte[] b = new byte[1024 * 5]; 
                   int len; 
                   while ( (len = input.read(b)) != -1) { 
                       output.write(b, 0, len); 
                   } 
                   output.flush(); 
                   output.close(); 
                   input.close(); 
               } 
               if(temp.isDirectory()){//如果是子文件夹 
                   copyFolder(oldPath+"/"+file[i],newPath+"/"+file[i]); 
               } 
           } 
       } 
       catch (Exception e) { 
           System.out.println("复制整个文件夹内容操作出错"); 
           e.printStackTrace(); 
       } 
   }
   public static void main(String args[]){
    BackUp bp = new BackUp();
    bp.copyFolder("D:\\a","E:\\b");
   }
}