如何读取非常大的文件，即100MB作为字符串

Question

My large_file.txt contains <tag> to represent data such as parents, childs and so on. My large_file.txt format is not xml format.

I want to read large_file.txt size 100 MB as a one string, then using String matching to get my data as a object.

Any help please?

Thanks in advance

Answer 1

I want to read large_file.txt size 100 MB as a one string

You really don't want to do that. You want to do anything you can to avoid it. You should always aim to process files a piece at a time. What happens when the file gets 10 times the size? 100? 1000?

Answer 2

http://bytes.com/topic/java/answers/17999-regex-whole-large-text-file

Answer 3

You can use Jakarta Regexp 's StreamCharacterIterator . This way you can directly apply string matching on the file without reading it first into a String object.

Otherwise you can use Commons IO's FileUtils .