FindJava: Update check to avoid accepting macOS stub 'java' as Java
Since commit dd378258 (FindJava: Do not accept OS X stub 'java' as Java, 2014-10-24, v3.1.0-rc3~29^2) we try to avoid using the macOS `/usr/bin/java` stub if no underlying implementation of Java is actually installed. However, the message that `/usr/bin/java` prints when there is no Java available has changed since then. Update our check to also look for the new message. While at it, revise the way we suppress `Java_JAVA_EXECUTABLE`. Previously we set its cache entry to `Java_JAVA_EXECUTABLE-NOTFOUND`, but that would cause the same find-and-reject sequence to be followed every time CMake runs in a build tree. Instead, use the approach from commit 2c0db404 (FindSubversion: Do not accept macOS stub without Xcode implementation, 2020-05-28, v3.18.0-rc1~67^2). Leave the cache entry alone and just set a normal variable of the same name to hide it.
Showing with 2 additions and 3 deletions