Where are Jetty's temporary directories?
Jetty itself has no temporary directories, but each web application can be assigned
a temporary directory. If the web application is a WAR file, it may be unpacked to the
webapp directory within the web applications temporary directory.
When assigning a temporary directory to a webapplication the following
locations are considered:
- The javax.servlet.context.tempdir attribute of the web application is check
to see if a directory name or a File has already been set.
- If a WEB-INF/work directory exists, it is used directly.
- If a ${jetty.home}/work directory exists, then a temp directory
is created within that directory.
- If no other location has been found, a temporary directory
is created within the ${java.io.tempdir} directory.
If a temporary directory is created, it is given a name based on
the first HttpListener within the HttpServer as follows:
"jetty_" + listener.getHost() + "_" + listener.getPort() + "_" + virtualHost + "_" + contextPath
Directories created within the java.io.tempdir are marked as deleteOnExit and
are not reused between invocations of the web application context.
Once a tempory directory has been allocated, a File instance for it
is set as the javax.servlet.context.tempdir attribute of the web
application.

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