用FilterInputStream对象读取大数据的一种优雅方法

Question

I am getting a FilterInputStream object as a return type from a function. Now the file which I will be getting as an stream is a log file. So I think it can be big file. So I do not want to read the data all at once. But reading data in a loop is kind of tedious job.

I need splitting at every newline, meaning data in file is in line separated format. With a constant size byte array to be used in public int read(byte[], int off, int len) as it will give rise to many cases. I do not want to read it at once because it can be of large size.

Is there an elegant way to do this.

PS: I am in particularly referring to S3ObjectInputStream extended from FilterInputStream which has read() function.

Answer 1

将BufferedReader包裹在FilterInputStream的InputStreamReader周围，​​并调用readLine().

Answer 2

OK, I am sorry, the next floor is right, you can use BufferedReader class, it has a method called readLine,and it returns a String object instead of a byte array. Just like this

BufferedReader reader = new BufferedReader(new FileReader(new File("the file path")));
String date = reader.readLine();
if(!StringUtil.isBlank(date)){
    //reade the file line by line
    date = reader.readLine();
}
reader.close();