[Java] Dealing with the situation where the program that writes to the Output Stream of Process does not end even if waitFor

-[Java] Enter into stdin of Process -Qiita

This is a problem that occurred while doing the contents of the above article.

problem

When I wrote to ʻOutputStream (= stdin)ofProcess, it did not end even if waitFor` with a time limit.

Problematic code

//Exception try-Assuming that catch is done outside
Process process = new ProcessBuilder(commands).start();

//Write to stdin
OutputStream os = process.getOutputStream();
os.write(multipartFile.getBytes());

boolean result = process.waitFor(5, TimeUnit.SECONDS);

Action / Cause

I tried to close OutputStream` and it was solved, so I think it was probably because I had to wait for writing endlessly.

After dealing

//Exception try-Assuming that catch is done outside
Process process = new ProcessBuilder(commands).start();

//Write to stdin
try (OutputStream os = process.getOutputStream()) {
  os.write(multipartFile.getBytes());
}

boolean result = process.waitFor(5, TimeUnit.SECONDS);