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Need help creating and installing capnpc-java (CapnProto for Java)

I have a project requiring the use of Cap'n Proto for Java. I have a Linux system and I've successfully installed the Cap'n Proto schema compiler as described here:

https://capnproto.org/install.html

Now following the installation instructions as described here: https://dwrensha.github.io/capnproto-java/index.html, I can't seem to figure out how to generate the capnpc-java plugin. The instructions here seem unclear:

You will need to install the latest release of the Cap’n Proto schema compiler. Then, running make should build capnpc-java.

Running make from where? I did that from the $WORKDIR/capnproto-java directory but that doesn't work.

The other approach I did was to follow the cmake instructions from from $WORKDIR/capnproto-java/cmake/README.md but that didn't work either. According to that README.md:

mkdir build
cd build
cmake -DCAPNP_PKG_PATH=[path of Capnproto pkgconfig directory (with capnp.pc)] [path of CMakeLists.txt]

Where I set CAPNP_PKG_PATH to be the path of the $WORKDIR/capnproto/c++/pkgconfig directory, and the [path of CMakeLists.txt] to $WORKDIR/capnproto, where $WORKDIR is a directory on my system.

Can anyone help? I'm not an expert on make system, Makefiles, or cmake. Where does the capnpc-java created? When I do a which capnpc-java, nothing is showing up (I do however, can successfully which capnp, which is located in /usr/local/bin/)

Solution

  • Looks like I figured it out after some trial and error. It's not straightforward from the README, but at the end of the day, I got the capnpc-java built. This is the approach I did:

    1. Per https://capnproto.org/install.html, follow the instructions From Git
    2. Go to $WORKDIR/capnproto-java/cmake. Follow the instructions in the README.md inside that cmake directory, under Using cmake.
    3. When specifying -DCAPNP_PKG_PATH, specify the path from Step 1, but make sure to include capnp.pc. For example: cmake -DCAPNP_PKG_PATH=$WORKDIR/capnproto/c++/pkgconfig/capnp.pc $WORKDIR/capnproto/CMakeLists.txt
    4. cd to $WORKDIR/capnproto and run make -j6
    5. cd to $WORKDIR/capnproto-java and run make
    6. capnpc-java is generated in $WORKDIR/capnproto-java. Copy this to /usr/local/bin

    I'm assuming this works. I haven't run the capnp compile yet, but at least this answered my original question.