Exception in thread "main" java.lang.NullPointerException
at java.io.Reader.<init>(Unknown Source)
at java.io.InputStreamReader.<init>(Unknown Source)
//at InputStreamReader inStream = new InputStreamReader(fis);
Exception in thread "main" java.lang.NullPointerException
at java.io.Reader.<init>(Unknown Source)
at java.io.InputStreamReader.<init>(Unknown Source)
//at InputStreamReader inStream = new InputStreamReader(fis);
此外,我应该添加抛出IOException,FileNotFoundException主或使用尝试{},而不是?异常在线程“主”java.lang.NullPointerException InputStreamReader
System.out.print("Enter the filename: ");
Scanner stdin = new Scanner(System.in); //Keyboard input
String fileName=stdin.nextLine();
FileInputStream fis = null;
try {
fis = new FileInputStream(fileName);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
InputStreamReader inStream = new InputStreamReader(fis);
BufferedReader in = new BufferedReader(inStream);
所以你的问题是出了什么问题和/或你应该怎么做? – nmagerko 2012-03-01 03:21:33
我认为这两个答案都会有所帮助。 – user93200 2012-03-01 03:24:04
看起来像您的文件输入流为空。您应该将代码的底部两行移入try块。作为一般惯例,吞并异常是一个糟糕的主意。 – Perception 2012-03-01 03:25:47