1 import java.io.BufferedInputStream; 2 import java.io.BufferedOutputStream; 3 import java.io.FileInputStream; 4 import java.io.FileOutputStream; 5 import java.io.InputStream; 6 import java.io.OutputStream; 7  8 /** 9  * 测试文件的读取、写入、复制功能10  * @package :java0511  * @author shaobn12  * @Describe :测试文件的读取、写入、复制功能13  * @Time: 2015-9-5 下午10:50:1814  */15 public class TestCopyText {16     public static void main(String[] args) throws Exception{17         //读取文件并打印18         System.out.println(readText(new FileInputStream("D:\\hello.txt")));19         //写入内容至文件20         writeText(new FileOutputStream("D:\\hellocopy.txt"), "您好，读写文件一般都用字符流，这种方式不推荐！");21         //复制文件，上面写入文件内容不变22         writeText(new FileOutputStream("D:\\hellocopy.txt",true),readText(new FileInputStream("D:\\hello.txt")));23     }24     //用FileInputStream读取文件25     public static String readText(InputStream is){26         BufferedInputStream bis = null;27         String str = null;28         try {29             bis = new BufferedInputStream(is);30             int len = 0;31             byte[] by = new byte[1024];32             while((len=bis.read(by))!=-1){33                 str = new String(by,0,len);34             }35         } catch (Exception e) {36             // TODO: handle exception37             e.printStackTrace();38         }finally{39             try {40                 if(bis!=null){41                     bis.close();42                     return str;43                 }44             } catch (Exception e2) {45                 // TODO: handle exception46                 e2.printStackTrace();47             }48         }49         return str;50     }51     //用FileOutputStream写入文件52     public static void writeText(OutputStream os,String str){53         BufferedOutputStream bos = null;54         try {55             bos = new BufferedOutputStream(os);56             bos.write(str.getBytes());57         } catch (Exception e) {58             // TODO: handle exception59             e.printStackTrace();60         }finally{61             try{62             if(bos!=null){63                 bos.close();64             }65             }catch (Exception e) {66                 // TODO: handle exception67                 e.printStackTrace();68             }69             70         }71         72     }73 }

声明一下：一般读写文本文件均为字符流，笔者用字节流来写，推荐大家使用字符流读写文本文件。