Java文件操作 读写操作

一、Java读取文件

案例1：读取D盘的1.txt文件

编码：

 File file = new File("D:/1.txt");
         FileReader fr = new FileReader(file);
         BufferedReader bf = new BufferedReader(fr);
         StringBuffer sbuffer = new StringBuffer();
         String temp = null;
         while((temp = bf.readLine()) !=null){
             sbuffer.append(temp+"\n");
         }
         System.out.println(sbuffer.toString());
 
         System.out.println();

结果：

二、写入文件

案例：讲D盘中的1.txt文件内容写入D盘一个2.txt文件。

编码：

 File file = new File("D:/1.txt");
         FileReader fr = new FileReader(file);
         BufferedReader bf = new BufferedReader(fr);
         StringBuffer sbuffer = new StringBuffer();
         String temp = null;
         while((temp = bf.readLine()) !=null){
             sbuffer.append(temp+"\n");
         }
         System.out.println(sbuffer.toString());
 
         System.out.println();
         File outfile = new File("D:/2.txt");
         if(!outfile.exists()){
             try {
                 outfile.createNewFile();
             } catch (IOException e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
             }
         }
         byte[] b = (sbuffer.toString()).getBytes();
         FileOutputStream fs = null;
         fs = new FileOutputStream(outfile);
         fs.write(b);
 
         fs.close();
         bf.close();