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README.md

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+# p≡p JNI Adapter
+
+## Prerequisites
+
+### yml2
+To set up yml2 properly, consult the documentation of pEp Engine (linked below). yml2 is a build dependency of pEp Engine.
+
+### C and C++ compiler
+Any gcc or clang distribution offered by your OS is fine.
+
+### pEp Engine
+Instructions for obtaining the pEp Engine can be found on [https://pep.foundation/dev/repos/pEpEngine/file/]().
+
+### libpEpAdapter
+Instructions for obtaining libpEpAdapter can be found on [https://pep.foundation/dev/repos/libpEpAdapter/file/]().
+
+### Java 8 (or newer) JDK
+Download Oracle Java from [https://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html]().
+
+OpenJDK can be installed from macports on macOS with one of the following commands:
+
+~~~
+sudo port install openjdk8
+sudo port install openjdk11
+~~~
+
+## Building
+Customization of the build can be done in `src/Makefile.conf`, or in a file `src/local.conf` which is not part of the source code distribution.
+
+An example `src/local.conf` looks like this:
+
+~~~
+JAVA_HOME=/Library/Java/JavaVirtualMachines/openjdk8/Contents/Home
+
+YML2_PATH=$(HOME)/code/yml2
+
+ENGINE_INC=-I$(HOME)/code/engine/build/include
+ENGINE_LIB=-L$(HOME)/code/engine/build/lib
+
+AD_INC=-L$(HOME)/code/libad/build/include
+AD_LIB=-L$(HOME)/code/libad/build/lib
+~~~
+
+Depending on what is already set in your environment, or can be found in your default include/library paths, setting any of these variables may be optional on your platform.
+
+Now, build the Adapter with
+
+~~~
+cd src
+make
+~~~