Java Reader markSupported()方法及示例

Java中Reader类的markSupported()方法是用来检查这个Reader是否支持mark()操作。它返回一个布尔值，说明该阅读器是否支持标记。

语法。

public boolean markSupported()

参数。该方法不接受任何参数

返回值。这个方法返回一个布尔值，告诉你这个阅读器是否支持mark()操作。如果它支持markSupported，它返回true。否则，它返回false。

下面的方法说明了markSupported()方法的工作。

程序 1:

// Java program to demonstrate// Reader markSupported() method  import java.io.*;import java.util.*;  class GFG {    public static void main(String[] args)    {          try {              String str = "GeeksForGeeks";              // Create a Reader instance            Reader reader                = new StringReader(str);              // Check if the Reader is            // markSupported using markSupported()            System.out.println("Is Reader markSupported: "                               + reader.markSupported());              reader.close();        }        catch (Exception e) {            System.out.println(e);        }    }}

输出:

Is Reader markSupported: true

程序2。

// Java program to demonstrate// Reader markSupported() method  import java.io.*;import java.util.*;  class GFG {    public static void main(String[] args)    {          try {            char[] str = { 'G', 'E', 'E', 'K', 'S' };              // Create a Reader instance            Reader reader                = new CharArrayReader(str);              // Check if the Reader is            // markSupported using markSupported()            System.out.println("Is Reader markSupported: "                               + reader.markSupported());              reader.close();        }        catch (Exception e) {            System.out.println(e);        }    }}

输出:

Is Reader markSupported: true

参考资料: https://docs.oracle.com/javase/9/docs/api/java/io/Reader.html#markSupported-