Create alternative launcher classes under the package
`org.springframework.boot.loader.launch` and use them in favor
of the previous location.
This update is designed to improve compatibility with future
changes in the loader.
Closes gh-37667
Update `spring-boot-smoke-test-ant` so that the ant lib folder is always
cleaned. Prior to this commit, it was possible for the folder to contain
stale artifacts.
Previously, the project version was included in the name of the
Ant-built jar and the integration test assumed that there would be a
single jar in the output directory. This assumption did not hold true
if the project's version had changed and the project had been built
again without a clean. This resulted in two jars, one for the previous
version and one for the current version, in the output directory. This
caused a test failure.
This commit updates the build.xml to remove the version from the name
of the Ant-built jar and updates the integration test to find it.
Closes gh-22782
Previously, we were adding dependencies to Ant's ClassLoader within
Gradle. It is suspected that this was causing sporadic loader
contraint violations as types that Gradle itself uses (from Commons
Compress) were then available from two different ClassLoaders.
This commit reworks the Ant smoke test to use JavaExec and Ant's
launcher to run the build. This allows us to make the necessary
dependencies available to Ant in an isolated manner. The javac
invocation within Ant is now forked to allow it to find the tools jar
even when the build itself is running on a JRE.
Closes gh-19839
