Update jar mode launchers to catch all exceptions and return a non-zero
exit code. This refinement also allows us to consolidate the existing
error reporting logic to a central locations. Modes that wish to report
a simple error rather than a full stacktrace can throw the newly
introduced `JarModeErrorException`.
Fixes gh-43435
Update `Path` creation for nested locations to allow both UNC and classic
file references to be used. This commit attempts to align our URL
handling with that of standard file URLs. The `NestedLocation` class
no longer attempts to remove leading all `\` characters and instead
only removes the first `\` when the second char is `:`. This duplicates
the logic found in Java's own internal `WindowsUriSupport` class which
is used when calling `Path.of(url)` with a `file:` URL.
Fixes gh-40549
Fix regression in `JarUrlConnection` where a NullPointerException could
be thrown internally causing performance issues.
When the SecurityManager is present, the following stack trace is
thrown:
java.lang.NullPointerException: Cannot invoke "java.net.URLConnection.getPermission()" because "this.jarFileConnection" is null
at org.springframework.boot.loader.net.protocol.jar.JarUrlConnection.getPermission(JarUrlConnection.java:175)
at java.base/jdk.internal.loader.URLClassPath.check(URLClassPath.java:553)
at java.base/jdk.internal.loader.URLClassPath$Loader.findResource(URLClassPath.java:612)
at java.base/jdk.internal.loader.URLClassPath.findResource(URLClassPath.java:296)
at java.base/java.net.URLClassLoader$2.run(URLClassLoader.java:629)
at java.base/java.net.URLClassLoader$2.run(URLClassLoader.java:627)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.net.URLClassLoader.findResource(URLClassLoader.java:626)
at org.springframework.boot.loader.net.protocol.jar.JarUrlClassLoader.findResource(JarUrlClassLoader.java:70)
at java.base/java.lang.ClassLoader.getResource(ClassLoader.java:1403)
at java.base/java.net.URLClassLoader.getResourceAsStream(URLClassLoader.java:290)
at java.base/java.lang.Class.getResourceAsStream(Class.java:2850)
See gh-39856
