Java PushbackReader reset()方法

java.io.PushbackReader.reset() 方法重置流。 PushbackReader复位方法总是抛出一个异常。

1 语法

public void reset()

2 参数

无

3 返回值

无

4 示例 

package com.yiidian;

/**
 * 一点教程网： http://www.yiidian.com
 */
/**
 * java.io.PushbackReader.reset()方法的例子
 */
import java.io.*;

public class Demo {
    public static void main(String[] args) {


        try {
            String s = "Hello World";

            // create a new StringReader
            StringReader sr = new StringReader(s);

            // create a new PushBack reader based on our string reader
            PushbackReader pr = new PushbackReader(sr, 20);

            // read the first five chars
            for (int i = 0; i < 5; i++) {
                char c = (char) pr.read();
                System.out.print("" + c);
            }

            // change line
            System.out.println();

            // try to reset and get an exception because it is not supported
            pr.reset();

            // close the stream
            pr.close();

        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
}

输出结果为：

Hello
java.io.IOException: mark/reset not supported
	at java.io.PushbackReader.reset(PushbackReader.java:228)
	at com.yiidian.Demo.main(Demo.java:34)