allow empty connections

Author: lausdahl

frameworks/fmi2/src/main/java/org/intocps/maestro/framework/fmi2/Fmi2SimulationEnvironmentConfiguration.java

@@ -32,10 +32,10 @@ public class Fmi2SimulationEnvironmentConfiguration {
     public Map<String, MultiModel.ModelSwap> modelSwaps;
 
     public Fmi2SimulationEnvironmentConfiguration(Map<String, List<String>> connections, Map<String, String> fmus) throws EnvironmentException {
-        if (connections == null || connections.size() < 1) {
-            throw new EnvironmentException("Cannot generate simulation environment configuration without any connections");
+        if (connections == null ) {
+            throw new EnvironmentException("Cannot generate simulation environment configuration if connections is null");
         }
-        if (fmus == null || fmus.size() < 1) {
+        if (fmus == null || fmus.isEmpty()) {
             throw new EnvironmentException("Cannot generate simulation environment configuration without FMUs");
         }
         validateFmusInConnectionsMatchesFmus(connections, fmus);

frameworks/fmi2/src/test/java/SimulationEnvironmentTest.java

@@ -9,13 +9,6 @@
 
 public class SimulationEnvironmentTest {
 
-    @Test
-    public void simConfThrowsWithoutConnections() {
-        // Assert
-        Assertions.assertThrows(EnvironmentException.class, () -> Fmi2SimulationEnvironmentConfiguration.createFromJsonString(new String(
-                Objects.requireNonNull(this.getClass().getClassLoader()
-                        .getResourceAsStream("simulation_environment" + "/simulation_environment_without_connections" + ".json")).readAllBytes())));
-    }
 
     @Test
     public void simConfThrowsWithoutFMUs() {