内容更改后如何重新读取文本文件的新内容？

Question

I would like to read a text file after the contents have changed, but Java is caching the original contents of the file.

I have tried URLConnection.setUsesCaches(false), which didn't help. I also tried adding a changing dummy query string parameter, but again no help

Resource[] resources = applicationContext.getResources("classpath*:/" + file);

for (Resource resource:resources) {
    URL url = resource.getURL();
//   reconstruct the URL to remove any possible vestiges of the resource
    url = new URL(url.toString());
    URLConnection conn = url.openConnection();
    conn.setUseCaches(false); // Tried this first, but it did not work!
//    url = new URL(url.toString() + "?dummy=" + id); // tried this also, but it doesn't work at all
    InputStream inputStream = conn.getInputStream();

Is there any way to tell Java to re-read the new contents of a file?

Answer 1

When you start your Spring on IDE, the classes are compiled to a specific output folder ( target folder in your case), static resources are also copied to respective folder.

It mean to be constant and immutable when start the app, you need to manual copy your file to target folder ( /target/classes/my-file.html ) to have it updated (Spring only look for files in that target folder).

But let re-think your implementation, it would be wrong from begining when you tried to update a static resource file.