The dobuild script is supposed to be reasonably straightforward. A simple
./dobuild jdk17u-jdk-17.0.8-ga
will download, patch, and build the relevant tag.
There are several flags you can use.
With -d, just download the given tag.
With -p, download if necessary, and apply patches.
With -b, download if necessary, apply patches, and run a build.
So, -b is the normal operation.
The variants -P and -B will delete an existing unpacked copy and start afresh.
In practice, what you'll want to do in development is use -p to check if any new patches apply cleanly, repeat with -P as you develop changes to the patches, then once you're happy do the build step.
You can use the -C flag to pass additional flags to configure, for example
-C --enable-jvm-feature-management
One part of the process is that you eventually need to use one version of the JDK in order to build the next. If it finds an installed version it will use that, but if you're building the whole chain from scratch you won't have that. So you can use the -i flag, for example
./dobuild -i jdk12u-jdk-12.0.2+10
will make that version of jdk12 available, ready for the jdk13 build.
The build process will generate a fully deployable image of the jdk, but it will be embedded in the build directory. The -i flag above knows where to find the image for use within another build, but if you want to deploy the build somewhere else then you'll need a standalone copy.
You can use the -e flag for this
./dobuild -e jdk-jdk-16-24
will generate a tarball called jdk-jdk-16-24.tar.gz that will unpack into a directory jdk-jdk-16-24, and will tell you where it's put it.
There are flags to control what patches get applied.
The -c flag allows you to specify which cpu patches will be applied. By default, it uses the cpu architecture of the system you're running the script on. Possible values: sparc
The -o flag allows you to specify which operating system patches will be applied. By default, it applies patches appropriate for the system you're running the script on. Possible values: solaris
These flags are designed to allow development and testing of patches. In general, overriding the cpu or os will cause the build to fail.
The -f flag allows you to apply patches for a specific feature. This is for any features that might be disabled by default.
There is some support here for running under Linux, specifically Debian SPARC. A caveat here is that /bin/sh is dash there, so you'll have to explicitly use bash:
bash dobuild ...