缓冲阅读器抛出异常答案

【问题标题】：Buffered Reader Throwing Exception缓冲阅读器抛出异常
【发布时间】：2020-10-24 00:05:49
【问题描述】：

我想打印 hello “t” 次。所以，我写了这段代码sn-p。


import java.util.*;
import java.io.*;

class Buff
{
    public static void main(String args[])
    {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        
        int t = Integer.parseInt(br.readLine());
        while(t-->0)
            bw.write("hello");

    }
}

输出异常


Buff.java:11: error: unreported exception IOException; must be caught or declared to be thrown
                String t = br.readLine();
                                      ^
Buff.java:14: error: unreported exception IOException; must be caught or declared to be thrown
                        bw.write("hello");

请帮忙！！！ PS：即使我抛出 IOException 也无济于事

【问题讨论】：

"PS : 即使我放了 throws IOException 也无济于事" – 你把这个 throws 放在哪里了？因为public static void main(String args[]) throws IOException {...} 应该适合你。

标签： java loops bufferedreader ioexception bufferedwriter

【解决方案1】：

您必须捕获可能的异常（在本例中为 IOException）。

基本语法如下所示：

try {
    //Your code here
}
catch(IOException e) {
    //What do you want to do when something went wrong?
}

在您的情况下，以下代码将起作用：

import java.util.*;
import java.io.*;

class Buff
{
    public static void main(String args[])
    {
        try {
            BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
            BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
            
            int t = Integer.parseInt(br.readLine());

            //Closing Readers and Writers when not needed anymore is good-practice
            br.close();

            //"-->" wasn't working for me in this case
            while(t > 0) {
                bw.write("hello\n");
                t--;
            }
            bw.flush();
            bw.close();
        }

        //Catching possible exceptions
        catch(IOException e) {
            e.printStackTrace();
        }

    }
}

【讨论】：