Java.io.Reader.mark() 方法

package com.codingdict;



import java.io.*;



public class ReaderDemo {



   public static void main(String[] args) {



      try {

         String s = "Hello World";



         // create a new StringReader

         Reader reader = new StringReader(s);



         // read the first five chars

         for (int i = 0; i < 5; i++) {

            char c = (char) reader.read();

            System.out.print("" + c);

         }



         // mark current position for maximum of 10 characters

         reader.mark(10);



         // read five more chars

         for (int i = 0; i < 6; i++) {

            char c = (char) reader.read();

            System.out.print("" + c);

         }



         // reset back to the marked position

         reader.reset();



         // change line

         System.out.println();



         // read six more chars

         for (int i = 0; i < 6; i++) {

            char c = (char) reader.read();

            System.out.print("" + c);

         }



         // close the stream

         reader.close();



      } catch (IOException ex) {

         ex.printStackTrace();

      }

   }

}