java io

    try {
         //File file=new File("D:\\cs\\ceshi.txt");
//       File file=new File("D:"+File.separator+"cs"+File.separator+"ceshi.txt");
//       System.out.println("file.getName() = " + file.getName());
//       System.out.println("file.getParent() = " + file.getParent());
//       System.out.println("file.getParentFile() = " + file.getParentFile());
//       System.out.println("file.getPath() = " + file.getPath());
//       System.out.println("file.isAbsolute() = " + file.isAbsolute());
//       System.out.println("file.getAbsolutePath() = " + file.getAbsolutePath());
//       System.out.println("file.canRead() = " + file.canRead());
//       System.out.println("file.canWrite() = " + file.canWrite());
//       System.out.println("file.exists() = " + file.exists());
//       System.out.println("file.isDirectory() = " + file.isDirectory());
//       System.out.println("file.isFile() = " + file.isFile());
//       System.out.println("file.lastModified() = " + new Date(file.lastModified()));
//       System.out.println("file.length() = " + file.length());
//       File f2=new File("\\java");
//       System.out.println("f2.getAbsolutePath() = " + f2.getAbsolutePath());
//       System.out.println("f2.exists() = " + f2.exists());
//       System.out.println("f2.mkdir() = " + f2.mkdir());
         /*File file=new File("D:"+File.separator+"cs"+File.separator+"ceshi.txt");
         RandomAccessFile rdf=null;
         //读写模式
         rdf=new RandomAccessFile(file,"rw");
         String name="zhangsan";
         int age=97;
         rdf.writeBytes(name);
         rdf.writeInt(age);
         name="lisi    ";
         age=98;
         rdf.writeBytes(name);
         rdf.writeInt(age);
         name="wangwu  ";
         age=99;
         rdf.writeBytes(name);
         rdf.writeInt(age);
         rdf.close();*/
         /*File file=new File("D:"+File.separator+"cs"+File.separator+"ceshi.txt");
         RandomAccessFile rdf=null;
         //读写模式
         rdf=new RandomAccessFile(file,"r");
         String name=null;
         int age=0;
         byte[] b = new byte[8];
         //跳过第一个人的信息
         rdf.skipBytes(12);
         for (int i = 0; i < b.length; i++) {
            //读取一个字节
            b[i]=rdf.readByte();
         }
         name=new String(b);
         age=rdf.readInt();
         System.out.println("第二个人的信息 --> 姓名：" + name + "；年龄：" + age) ;
         // 读取第一个人的信息// 指针回到文件的开头
         rdf.seek(0) ;
         for (int i = 0; i < b.length; i++) {
            b[i]=rdf.readByte();
         }
         name = new String(b) ;  // 将读取出来的byte数组变为字符串
         age = rdf.readInt() ;   // 读取数字
         System.out.println("第一个人的信息 --> 姓名：" + name + "；年龄：" + age) ;
         rdf.skipBytes(12) ; // 跳过第二个人的信息
         for (int i = 0; i < b.length; i++) {
            b[i]=rdf.readByte();
         }
         name = new String(b) ;  // 将读取出来的byte数组变为字符串
         age = rdf.readInt() ;   // 读取数字
         System.out.println("第三个人的信息 --> 姓名：" + name + "；年龄：" + age) ;
         rdf.close();*/
         /*File file=new File("D:"+File.separator+"cs"+File.separator+"test.txt");
         OutputStream out=new FileOutputStream(file);
         String str="Hello World";
         byte[] bytes = str.getBytes();
         out.write(bytes);
//       out.close();*/
/*       File file=new File("D:"+File.separator+"cs"+File.separator+"test2.txt");
         Writer writer=new FileWriter(file);
         String str="Hello World 2";
         byte[] bytes = str.getBytes();
         writer.write(str);
         writer.flush();
//       writer.close();*/
         /*
//读取txt每一行数据
         File file=new File("D:"+File.separator+"cs"+File.separator+"test2.txt");
         BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
         String str=null;
         while ((str=reader.readLine())!=null){
            System.out.println("str = " + str);
         }
         reader.close();*/
      /*
//获取输入的第一个字符
         System.out.print("Enter a Char:");
         char i = (char)System.in.read();
         System.out.println("Yout Enter Char is:" + i);*/
      } catch (Exception e) {
         e.printStackTrace();
      }