On Sat, 4 Mar 2023 21:49:20 GMT, Jesse Glick <[email protected]> wrote:

> [JDK-6956385](https://bugs.openjdk.org/browse/JDK-6956385): 
> `JarURLConnection` properly tracks any `InputStream` it itself opened, and 
> correspondingly closes the `JarFile` if necessary (when caches are disabled). 
> However if its underlying `FileURLConnection` was used to retrieve a header 
> field, that would have caused a `FileInputStream` to be opened which never 
> gets closed until it is garbage collected. This means that an application 
> which calls certain methods on `jar:file:/…something.jar!/…` URLs will leak 
> file handles, even if `URLConnection` caches are supposed to be turned off. 
> This can delay release of system resources, and on Windows can prevent the 
> JAR file from being deleted even after it is no longer in use (for example 
> after `URLClassLoader.close`).
> 
> [JDK-8224095](https://bugs.openjdk.org/browse/JDK-8224095) was marked as a 
> duplicate, but I think incorrectly. It refers to `FileURLConnection`, and 
> seems to be complaining about the confusing API design of `URLConnection` 
> generally: that it is an object which you might expect to be `Closeable` but 
> in fact it is its `inputStream` which must be `close`d. In JDK-6956385, even 
> when the caller _does_ specifically call `InputStream.close`, a file handle 
> may be leaked.
> 
> I managed to build the JDK on both Linux and (Cygwin) Windows to confirm the 
> fix via
> 
> 
> ./build/…-x86_64-server-release/jdk/bin/java 
> test/jdk/sun/net/www/protocol/jar/FileURLConnectionLeak.java
> 
> 
> I also ran jtreg on Linux (this test and various others in nearby packages); 
> on Windows the `make test` target just hung for some reason.
> 
> I marked the test `othervm` out of caution, since it is mutating global 
> state, and if it fails will leak a handle and prevent scratch dir cleanup on 
> Windows.
> 
> (This is my first contribution, at least after the move to GitHub, so let me 
> know if something is missing here technically or stylistically. None of the 
> contribution guides appear to be up to date.)

(still trying to get formal confirmation from my employer that I can mark the 
OCA as signed)

https://oca.opensource.oracle.com/?ojr=contrib-list shows CloudBees, Inc.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/12871#issuecomment-1523867700
PR Comment: https://git.openjdk.org/jdk/pull/12871#issuecomment-1535109704

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