Java Java.io.CharArrayReader.markSupported()用法及代碼示例

描述

這個java.io.CharArrayReader.markSupported()方法測試流是否支持 mark()。字符數組讀取器支持 mark() 方法。

聲明

以下是聲明java.io.CharArrayReader.markSupported()方法≫

public boolean markSupported()

參數

NA

返回值

如果流支持 mark() 調用，則該方法返回 true。

異常

NA

示例

下麵的例子展示了 java.io.CharArrayReader.markSupported() 方法的用法。

package com.tutorialspoint;

import java.io.CharArrayReader;
import java.io.IOException;

public class CharArrayReaderDemo {
   public static void main(String[] args) {      CharArrayReader car = null;
      char[] ch = {'A', 'B', 'C', 'D', 'E'};

      try {
         // create new character array reader
         car = new CharArrayReader(ch);
         
         // verifies if the stream support mark() method
         boolean bool = car.markSupported();
         System.out.println("Is mark supported:"+bool);
         System.out.println("Proof:");
         
         // read and print the characters from the stream
         System.out.println(car.read());
         System.out.println(car.read());
         
         // mark() is invoked at this position
         car.mark(0);
         System.out.println("Mark() is invoked");
         System.out.println(car.read());
         System.out.println(car.read());
         
         // reset() is invoked at this position
         car.reset();
         System.out.println("Reset() is invoked");
         System.out.println(car.read());
         System.out.println(car.read());
         System.out.println(car.read());
         
      } catch(IOException e) {
         // if I/O error occurs
         e.printStackTrace();
      } finally {
         // releases any system resources associated with the stream
         if(car!=null)
            car.close();
      }
   }
}

讓我們編譯並運行上麵的程序，這將產生以下結果——

Is mark supported:true
Proof:
65
66
Mark() is invoked
67
68
Reset() is invoked
67
68
69