For the most part, follow the instructions at https://github.com/openjdk/jdk/blob/jdk-21%2B35/doc/building.md#tldr-instructions-for-the-impatient.
- Clone the repository and get the tag you care about
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git clone https://github.com/openjdk/jdk.git cd jdk git fetch origin tag jdk-21+35 git checkout jdk-21+35 - Note: this fetch fetched way more than I wanted. It was over 1GB, but whatever.
-
- Create your own branch so that you aren't in a detached state
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git switch -c david-jdk-21
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- Install Autoconf
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brew install autoconf
-
- Install a "bootstrap JDK"
- I had a Temurin distribution of Java 21 installed via SDKMAN, and the Autoconf found it.
- Configure the system for building (like a pre-check)
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bash configure
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- (Optional) Clean up old builds
- If you had previously cloned the code and executed a build you will want to first clean the project. Execute the following command.
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make clean
- Build
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make images
- Note: you might have permissions problems.
- Wait for a few minutes (wow it was only 2-3 minutes on my M2 Pro, but I remember like an hour on my 2018 intel Macbook Air)
-
- Verify the built JDK
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build/macosx-aarch64-server-release/images/jdk/bin/java --version
- SUCCESS
-
- (Optional) Link it with SDKMAN
- Link it as an SDKMAN candidate version with something like the following.
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sdk install java 21_2024-03-20 /Users/dave/repos/opensource/jdk/build/macosx-aarch64-server-release/images/jdk