bhoran/langchain4j-searchbot

Native LangChain4J SearchBot

Native LangChain4j Searchbot

This is a Java command-line chatbot application that leverages LangChain4j and the OPENAI API model "gpt-4".

LangChain4j is a Java version of LangChain to simplify integrating AI/LLM capabilities into Java applications.

The example is based on a LangChain4j tutorial. This application is enhanced with GraalVM Native Image Maven plugin that enables you to easily create a native executable for a Java application.

The goal of this project is to demonstrate:

• how easy it is to ahead-of-time compile a CLI application that uses the LLM
• the use of Profile-guided optimizations and SBOM Native Image features

Prerequisites

• GraalVM JDK (sdk install java 21.0.2-graal)
• Maven
• OPENAI API key

NOTE: To interact with the OpenAI API, you need to either get and store an OPENAI API key in an environment variable OPENAI_API_KEY.

Package the Aplication into a Native Executable Using with Maven

1. Clone this repository with Git and then enter it:

   git clone https://github.com/olyagpl/langchain4j-searchbot.git

   cd langchain4j-searchbot

2. Compile and create a JAR file with all dependencies (required for Native Image):

   $ mvn clean package

3. Create a native executable using the Maven plugin for Native Image:

   $ mvn -Pnative package

   This produces a Linux self-contained executable version of the seachbot!

4. Interact with the seachbot:

   $ ./target/searchbot “Why should I visit Lviv?”

Apply Profile-Guided Optimizations to Create an Optimized Native Executable

Profile-Guided Optimizations is the technique fetching the profiling information to the AOT compiler to improve the performance and file size of a native executable.

1. Build an “instrumented” executable and run it to gather profiles:

   $ native-image -jar ./target/searchbot-1.0-jar-with-dependencies.jar --pgo-instrument -o ./target/searchbot-instrumented

   $ ./target/searchbot-instrumented “What is the weather today?”

2. Build a PGO-optimized executable that will pick up the gathered profiles, and run:

   $ native-image -jar ./target/searchbot-1.0-jar-with-dependencies.jar --pgo -o ./target/searchbot-pgo-optimized

   $ ./target/searchbot-pgo-optimized “What is JavaDay Lviv”

Learn More

• Native Image Documentation on Profile-Guided Optimizations