Each one has a slightly different macOS installer. Some are .pkg files that write to /Library/Java . Some are .tar.gz that you manually place in /usr/local . No matter which JDK you download, macOS has multiple Java versions lurking. Apple even ships a legacy 1.6 stub in some systems (don’t ask).
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Use /usr/libexec/java_home – Apple’s secret weapon: Each one has a slightly different macOS installer