Java扫描器空指针在while (line != Null)循环中出现异常

Question

我试着在我的文本文件中找到多少fender单词，但我得到nullPointerException。我在等待你的帮助。谢谢你:)

public class ScanTxt {
private static BufferedReader buffer;
static int count=0;

public static void main(String...args) throws IOException{
readFile();
}
public static int readFile() throws IOException {
    buffer = new BufferedReader(new FileReader("C:/Users/ASUS/Desktop/myfile.txt"));
        StringBuilder strbuild = new StringBuilder();
        String line = bufferr.readLine();
        while (line!=null) {
            strbuild.append(line);
            strbuild.append("n");
            line = buffer.readLine();
            if(line.equalsIgnoreCase("fender")){
                count++;
            }
        }
        return count;

}

Answer 1

你正在阅读你的行很快在while内，所以它可以是null在line.equalsIgnoreCase(当你的while循环停止)

试

   while (line!=null) {
        strbuild.append(line);
        strbuild.append("n");
        if(line.equalsIgnoreCase("fender")){
            count++;
        }
        line = buffer.readLine();
    }