Weaviate Java client

A Java native client for weaviate.

Usage

In order to get start using the java client one needs to add it's dependency:

<dependency>
  <groupId>io.weaviate</groupId>
  <artifactId>client</artifactId>
  <version>4.6.0</version>
</dependency>

For applications on Java 9 or above

The client utilizes Gson for JSON serialization/deserialization and Gson uses reflection of internal java.lang classes to do it. This is not allowed by default in Java 9 and above.

To work around this, it's necessary to add this JVM commandline argument:

--add-opens=java.base/java.lang=ALL-UNNAMED

If you're using Gradle, you can add this instead to your application block in your build.gradle.kts file:

applicationDefaultJvmArgs += listOf(
  "--add-opens=java.base/java.lang=ALL-UNNAMED",
)

Here's a simple code to start up working with Java client:

Add dependency to your java project.
Connect to Weaviate on localhost:8080 and fetch meta information

package io.weaviate;

import io.weaviate.client.Config;
import io.weaviate.client.WeaviateClient;
import io.weaviate.client.base.Result;
import io.weaviate.client.v1.misc.model.Meta;

public class App {
  public static void main(String[] args) {
    Config config = new Config("http", "localhost:8080");
    WeaviateClient client = new WeaviateClient(config);
    Result<Meta> meta = client.misc().metaGetter().run();
    if (meta.hasErrors()) {
      System.out.printf("Error: %s\n", meta.getError().getMessages());
    } else {
      System.out.printf("meta.hostname: %s\n", meta.getResult().getHostname());
      System.out.printf("meta.version: %s\n", meta.getResult().getVersion());
      System.out.printf("meta.modules: %s\n", meta.getResult().getModules());
    }
  }
}