How to merge >1000 xml files into one using Java

Question

I am trying to merge many xml files into one. I have successfully done that in DOM, but this solution is limited to a few files. When I run it on multiple files >1000 I am getti

Answer 1

For this kind of work I will suggest not to use DOM, reading the file content and making a substring is simpler and enough.

I'm thinking of something like that :

String rootContent = document.substring(document.indexOf(""), document.lastIndexOf("")+7);

Then to avoid to much memory consummation. Write in the main file after every xml extraction with a BufferedWritter for example. For better performance you can also use java.nio.