When resolving resources, the PathResourceResolver creates a Resource
instance and checks whether this resource `exists()` and `isReadable()`.
While that last call returns false for folders on the file system, both
calls return true for folders located inside JARs.
If a JAR location is configured as a resource location, then
PathResourceResolver can resolve folders in JARs as valid locations and
candidates for paths resolution.
Prior to this change, the PathResourceResolver would resolve "" as a
valid resource path (here, the "/META-INF/resources/webjars" if
configured, for example) and return a "" path for this resource,
effectively turning all "/" URLs into empty ones "".
This commit fixes the resolveUrlPathInternal implementation by not
allowing empty paths as valid resource paths.
Issue: SPR-13241
This commit adds a new sharedEngine property to ScriptTemplateConfigurer
and ScriptTemplateView in order to support non thread-safe ScriptEngine
implementations like Nashorn.
When this flag is set to false, the engine is retrieved from a
ThreadLocal<ScriptEngine> field instead of a ScriptEngine one.
Also as part of this commit, all the initialization logic has been moved from
ScriptTemplateConfigurer to ScriptTemplateView since the script engine can
now be lazily initialized multiple time in the view when sharedEngine is
set to false.
Issue: SPR-13034
Some databases such as Oracle permit double quoted column aliases that
contain case-sensitive characters, single quotes, and other special
characters; however, prior to this commit, SqlScripts interpreted a
single quote nested within double quotes as the start of a string
literal resulting in improper parsing.
This commit addresses this issue by ensuring that double quoted strings
such as column aliases are properly parsed even when containing single
quotes.
Issue: SPR-13218
When using an Apache Http components based infrastructure, a null header
value is handled as the empty string. The exact same infrastructure using
HttpURLConnection generates a header with no colon. This is actually not
proper HTTP and some components fail to read such request.
We now make sure to call HttpURLConnection#addRequestProperty with the
empty String for a null header value.
Issue: SPR-13225