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Java

The Java client is for JVM applications that call the sysml-grpc service without taking ownership of their host application's runtime or transport. Its typed immutable results are useful in desktop tooling, servers and Eclipse-based integrations.

Install

The artifact is not on Maven Central. Build and install it into the local Maven repository from a checkout; JDK 17 is the baseline:

make build-grpc
mvn -f client/java/pom.xml install

Then add org.openmbee:opensysml at the matching client version to the consumer's pom.xml.

First model

Connection.parse accepts inline SysML. Check the model diagnostics, then evaluate the subject's redefined mass:

import org.openmbee.opensysml.Connection;
import org.openmbee.opensysml.Diagnostic;
import org.openmbee.opensysml.Model;
import org.openmbee.opensysml.Value;

public class Demo {
  public static void main(String[] args) throws Exception {
    String source = """
        package Demo {
          part def Vehicle {
            attribute mass default = 1500.0;
          }
          part sedan : Vehicle {
            attribute :>> mass = 1800.0;
          }
        }
        """;

    try (Connection connection = Connection.open()) {
      Model model = connection.parse(source);
      if (!model.ok()) {
        for (Diagnostic diagnostic : model.diagnostics()) System.err.println(diagnostic);
        throw new IllegalStateException("The model has errors.");
      }

      Value value = model.evalWithSubject("mass", "Demo::sedan");
      if (!(value instanceof Value.RealValue real)) {
        throw new IllegalStateException("Expected a real value.");
      }
      System.out.printf("%.1f%n", real.value());
    }
  }
}

1800.0

Connection.open() owns the private child it starts and closes it with the connection. A connection can instead target a service owned by the application or another process. The client also provides symbol lookup, instantiation, verification, analysis, execution, queries and source edits.

Service source

The Java client starts a private service by default and can also connect to an explicitly managed service. See the service-binary reference for the binary lookup order, version requirements and verification options.

Invalid models expose their parse diagnostics through Model; unsupported service capabilities raise a typed exception before the client makes a capability-gated call.

Next steps