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+"
");
        }
        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+"
");
        }
        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();