filterreader_Java FilterReader markSupported（）方法与示例

filterreader

FilterReader类markSupported()方法 (FilterReader Class markSupported() method)

markSupported() method is available in java.io package.
markSupported()方法在java.io包中可用。
markSupported() method is used to check whether this FilterReader stream support mark() method or not.
markSupported()方法用于检查此FilterReader流是否支持mark()方法。
markSupported() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
markSupported()方法是一种非静态方法，只能通过类对象访问，如果尝试使用类名称访问该方法，则会收到错误消息。
markSupported() method does not throw an exception at the time of checking supporting methods.
在检查支持方法时， markSupported()方法不会引发异常。

Syntax:

句法：

    public boolean markSupported();

Parameter(s):

参数：

It does not accept any parameter.
它不接受任何参数。

Return value:

返回值：

The return type of the method is boolean, it returns true when this stream support mark() method otherwise it returns false.

该方法的返回类型是布尔值，当此流支持标记()方法，否则返回false返回true。

Example:

例：

// Java program to demonstrate the example 
// of boolean markSupported() method of FilterReader
import java.io.*;
public class MarkSupportedOfFR {
public static void main(String[] args) throws Exception {
Reader r_stm = null;
FilterReader fr_stm = null;
try {
// Instantiates StringReader and 
// FilterReader
r_stm = new StringReader("JavaWorld!!!!");
fr_stm = new FilterReader(r_stm) {};
// By using markSupported() method is to
// check whether the stream fr_stm support
// mark() or not
boolean status = fr_stm.markSupported();
System.out.println("fr_stm.markSupported(): " + status);
} catch (Exception ex) {
System.out.println(ex.toString());
} finally {
// with the help of this block is to
// free all necessary resources linked
// with the stream
if (fr_stm != null) {
fr_stm.close();
}
}
}
}

Output

输出量