From fe77f8242347d0aad7aaa9869bcaf5fa9b810fce Mon Sep 17 00:00:00 2001
From: Alex Eftimiades <alexeftimiades@gmail.com>
Date: Fri, 31 Jul 2020 09:54:43 -0400
Subject: [PATCH] python java interop demo

---
 python-java/README.md                    |  3 +
 python-java/pom.xml                      | 97 ++++++++++++++++++++++++
 python-java/src/clj/picklejar/core.clj   |  3 +
 python-java/src/java/picklejar/Main.java | 17 +++++
 4 files changed, 120 insertions(+)
 create mode 100644 python-java/README.md
 create mode 100644 python-java/pom.xml
 create mode 100644 python-java/src/clj/picklejar/core.clj
 create mode 100644 python-java/src/java/picklejar/Main.java

diff --git a/python-java/README.md b/python-java/README.md
new file mode 100644
index 0000000..097d48c
--- /dev/null
+++ b/python-java/README.md
@@ -0,0 +1,3 @@
+# FFI To Python From Java
+
+Beginner friendly wrapper from Python to Java through [libpython-clj](https://github.com/clj-python/libpython-clj). Demonstrates a minimal project that imports custom Clojure code and interfaces with Python from Java.
diff --git a/python-java/pom.xml b/python-java/pom.xml
new file mode 100644
index 0000000..9f02140
--- /dev/null
+++ b/python-java/pom.xml
@@ -0,0 +1,97 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>picklejar</groupId>
+    <artifactId>picklejar</artifactId>
+    <packaging>jar</packaging>
+    <version>0.1.0-SNAPSHOT</version>
+    <name>picklejar</name>
+    <properties>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+    </properties>
+    <description/>
+    <licenses>
+        <license>
+            <name>Eclipse Public License</name>
+            <url>http://www.eclipse.org/legal/epl-v10.html</url>
+        </license>
+    </licenses>
+    <scm/>
+    <build>
+        <sourceDirectory>src/java</sourceDirectory>
+        <resources>
+            <resource>
+                <directory>src/clj</directory>
+            </resource>
+        </resources>
+        <testResources>
+            <testResource>
+                <directory>test/clj</directory>
+            </testResource>
+        </testResources>
+        <directory>target</directory>
+        <outputDirectory>target/class-files</outputDirectory>
+        <plugins>
+            <plugin>
+                <artifactId>maven-assembly-plugin</artifactId>
+                <configuration>
+                    <archive>
+                        <manifest>
+                            <mainClass>picklejar.Main</mainClass>
+                        </manifest>
+                    </archive>
+                    <descriptorRefs>
+                        <descriptorRef>jar-with-dependencies</descriptorRef>
+                    </descriptorRefs>
+                </configuration>
+                <executions>
+                    <execution>
+                        <id>make-assembly</id>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>single</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+    <repositories>
+        <repository>
+            <id>central</id>
+            <url>https://repo1.maven.org/maven2/</url>
+            <snapshots>
+                <enabled>false</enabled>
+            </snapshots>
+            <releases>
+                <enabled>true</enabled>
+            </releases>
+        </repository>
+        <repository>
+            <id>clojars</id>
+            <url>https://repo.clojars.org/</url>
+            <snapshots>
+                <enabled>true</enabled>
+            </snapshots>
+            <releases>
+                <enabled>true</enabled>
+            </releases>
+        </repository>
+    </repositories>
+    <dependencyManagement>
+        <dependencies/>
+    </dependencyManagement>
+    <dependencies>
+        <dependency>
+            <groupId>org.clojure</groupId>
+            <artifactId>clojure</artifactId>
+            <version>1.10.2-alpha1</version>
+        </dependency>
+        <dependency>
+            <groupId>clj-python</groupId>
+            <artifactId>libpython-clj</artifactId>
+            <version>1.45</version>
+        </dependency>
+    </dependencies>
+</project>
diff --git a/python-java/src/clj/picklejar/core.clj b/python-java/src/clj/picklejar/core.clj
new file mode 100644
index 0000000..8021a7f
--- /dev/null
+++ b/python-java/src/clj/picklejar/core.clj
@@ -0,0 +1,3 @@
+(ns picklejar.core
+    (:require [libpython-clj.require :refer [require-python]]
+              [libpython-clj.python :refer [py. py.. py.-] :as py]))
diff --git a/python-java/src/java/picklejar/Main.java b/python-java/src/java/picklejar/Main.java
new file mode 100644
index 0000000..23cb9d1
--- /dev/null
+++ b/python-java/src/java/picklejar/Main.java
@@ -0,0 +1,17 @@
+package picklejar;
+import clojure.java.api.Clojure;
+import clojure.lang.IFn;
+
+public class Main {
+  public static void main(String[] args) {
+    System.out.println("java main - enter");
+    IFn require = Clojure.var("clojure.core", "require");
+    // For using custom Clojure:
+    // require.invoke(Clojure.read("picklejar.core"));
+    require.invoke(Clojure.read("libpython-clj.require"));
+    require.invoke(Clojure.read("libpython-clj.python"));
+    IFn require_python = Clojure.var("libpython-clj.require", "require-python");
+    require_python.invoke(Clojure.read("numpy"));
+    System.out.println("java main - done");
+  }
+}