zeppelin/java

Overview

Java interpreter for Apache Zeppelin

Architecture

Current interpreter implementation supports the static REPL. It compiles the code in memory, execute it and redirect the output to Zeppelin.

Technical overview

• Upon starting an interpreter, an instance of JavaCompiler is created.

• When the user runs commands with java, the JavaParser go through the code to get a class that contains the main method.

• Then it replaces the class name with random class name to avoid overriding while compilation. It creates new out & err stream to get the data in new stream instead of the console, to redirect output to Zeppelin.

• If there is any error during compilation, it can catch and redirect to Zeppelin.

• JavaInterpreterUtils contains useful methods to print out Java collections and leverage Zeppelin's built in visualization.