Scanner遇上UnmappableCharacterException

上周末的时候，朋友约好去KTV，鉴于我这种不怎么听歌的孩子伤不起啊，灵机一动就把我的酷狗歌单导出来了，XML文件嘛，内容太多，我只想要歌名足已。于是写了一个java去输出歌名。

岂料我受到了挫伤，scanner.hasNextLine()一直为false，于是我百思不得姐啊，经过调试发现，Scanner内部有java.nio.charset.UnmappableCharacterException，就百度了一下，没找到答案，google访问不了，想起公司的网络是香港的，就远程上去，还好在stackoverflow上找到了答案。O(∩_∩)O~~

原来用改动下面一行就OK啦，不解释，你懂的，不懂就去stackoverflow。

Scanner scanner=new Scanner(new File(filePath),"UTF-8");

URL：http://stackoverflow.com/questions/19252321/findwithinhorizon-fails-to-match （这个页面上你可以学到更多） 

Java Code：

public void output(String filePath) throws FileNotFoundException{
        Scanner scanner=new Scanner(new File(filePath));
        String str=null;
        while(scanner.hasNextLine()){
            str=scanner.nextLine();
            if(str.indexOf("FileName")>0){
                System.out.println(str.substring(str.indexOf(">")+1, str.lastIndexOf("<")));
            }
        }
        scanner.close();
    }  

File content：

<File>
	<MediaFileType>0</MediaFileType>
	<FileName>周杰伦 - 爱在西元前.mp3</FileName>
	<FilePath>D:\music\</FilePath>
	<FileSize>5623610</FileSize>
	<Duration>234292</Duration>
	<Hash>0589341ba15528a4c63e36c49a3c0e45</Hash>
	<Lyric>E:\KuGou\Lyric\周杰伦 - 爱在西元前-0589341ba15528a4c63e36c49a3c0e45.krc</Lyric>
	<Bitrate>192004</Bitrate>
	<MandatoryBitrate>0</MandatoryBitrate>
</File>

Java Code after modify：

public void output(String filePath) throws FileNotFoundException{
		Scanner scanner=new Scanner(new File(filePath),"UTF-8");//Always explicitly pass a charset when working with text
		String str=null;
		while(scanner.hasNextLine()){
			str=scanner.nextLine();
			if(str.indexOf("FileName")>0)
				System.out.println(str.substring(str.indexOf(">")+1, str.lastIndexOf("<")));
		}
		//It‘s better to check IOException when working with Scanner(PS:find UnmappableCharacterException took me more time,finally by debug to found )
		IOException ioException = scanner.ioException();
		if (ioException != null) {
		    ioException.printStackTrace();
		}

		scanner.close();
	}

Scanner遇上UnmappableCharacterException