java.io.ByteArrayInputStream.markSupported() 如果输入流是否支持mark() 和reset()方法的调用方法返回true。对于ByteArrayInputStream类的方法总是返回true。

声明

以下是java.io.ByteArrayInputStream.markSupported()方法的声明：

public boolean markSupported()

参数

• NA

返回值

这种方法对于ByteArrayInputStream类返回true

异常

• NA

例子

下面的示例演示java.io.ByteArrayInputStream.markSupported()方法的用法。

package com.yiibai;

import java.io.ByteArrayInputStream;
import java.io.IOException;

public class ByteArratInputStreamDemo {
   public static void main(String[] args) throws IOException {
      
      byte[] buf = {65, 66, 67, 68, 69};
      ByteArrayInputStream bais = null;
      
      try{
         
         // create new byte array input stream
         bais = new ByteArrayInputStream(buf);
         
         // test support for mark() and reset() methods invocation
         boolean isMarkSupported = bais.markSupported();
         System.out.println("Is mark supported : "+isMarkSupported);
         System.out.println("Following is the proof:");
         
         // print bytes
         System.out.println("Byte read "+ bais.read());
         System.out.println("Byte read "+ bais.read());
         System.out.println("Byte read "+ bais.read());
         
         System.out.println("Mark() invocation");

         // mark() invocation;
         bais.mark(0);
         System.out.println("Byte read "+ bais.read());
         System.out.println("Byte read "+ bais.read());
         
         System.out.println("Reset() invocation");
         
         // reset() invocation
         bais.reset();
         System.out.println("Byte read "+ bais.read());
         System.out.println("Byte read "+ bais.read());
         
      }catch(Exception e){

         // if I/O error occurs
         e.printStackTrace();
      }finally{
         if(bais!=null)
            bais.close();
      }   
   }
}

让我们来编译和运行上面的程序，这将产生以下结果：

Is mark supported : true
Following is the proof:
Byte read 65
Byte read 66
Byte read 67
Mark() invocation
Byte read 68
Byte read 69
Reset() invocation
Byte read 68
Byte read 69