solves #191

In case entities are extended from each other, the code generation for the static meta model will fail due to a NullPointerException.
This happened in the DefaultAbstractEntity:.getExtendingElements due to a map without excluding null Objects.

Author: DvSmi

core/sds-aspect-meta-model-java/src/main/java/io/openmanufacturing/sds/metamodel/impl/DefaultAbstractEntity.java

@@ -14,6 +14,7 @@
 package io.openmanufacturing.sds.metamodel.impl;
 
 import java.util.List;
+import java.util.Objects;
 import java.util.Optional;
 import java.util.stream.Collectors;
 
@@ -52,7 +53,7 @@ private DefaultAbstractEntity( final MetaModelBaseAttributes metaModelBaseAttrib
     */
    @Override
    public List<ComplexType> getExtendingElements() {
-      return extendingElements.stream().map( instances::get ).collect( Collectors.toList() );
+      return extendingElements.stream().map( instances::get ).filter( Objects::nonNull ).collect( Collectors.toList() );
    }
 
    /**

core/sds-aspect-model-java-generator/src/test/java/io/openmanufacturing/sds/aspectmodel/java/StaticMetaModelJavaGeneratorTest.java

@@ -52,6 +52,7 @@
 import io.openmanufacturing.sds.staticmetamodel.constraint.StaticConstraintContainerProperty;
 import io.openmanufacturing.sds.staticmetamodel.constraint.StaticConstraintProperty;
 import io.openmanufacturing.sds.test.TestAspect;
+import io.openmanufacturing.sds.test.TestSharedAspect;
 
 public class StaticMetaModelJavaGeneratorTest extends StaticMetaModelGeneratorTest {
 
@@ -65,6 +66,17 @@ public void testCodeGeneration( final TestAspect testAspect ) {
       assertThatCode( () -> TestContext.generateStaticAspectCode().apply( getGenerators( testAspect, KnownVersion.getLatest() ) ) ).doesNotThrowAnyException();
    }
 
+   /**
+    * Tests that code generation succeeds for all test models for the latest meta model version
+    * @param testAspect the injected Aspect model
+    */
+   @ParameterizedTest
+   @EnumSource( value = TestSharedAspect.class )
+   public void testCodeGenerationSharedAspect( final TestSharedAspect testAspect ) {
+      assertThatCode( () -> TestContext.generateStaticAspectCode().apply( getGenerators( testAspect, KnownVersion.getLatest() ) ) ).doesNotThrowAnyException();
+   }
+
+
    @ParameterizedTest
    @MethodSource( value = "allVersions" )
    public void testGenerateStaticMetaModelWithOptionalProperties( final KnownVersion metaModelVersion ) throws IOException {
@@ -142,6 +154,18 @@ ImmutableMap.<String, Object> builder().put( "NAMESPACE", String.class ).put( "M
                   } ).build(), new HashMap<>() );
    }
 
+   @ParameterizedTest
+   @MethodSource( value = "versionsStartingWith2_0_0" )
+   public void testGenerateStaticMetaModelWithMeasurementTwo( final KnownVersion metaModelVersion ) throws IOException {
+      final TestAspect aspect = TestAspect.ASPECT_WITH_EXTENDED_ENTITY;
+      final StaticClassGenerationResult result = TestContext.generateStaticAspectCode().apply( getGenerators( aspect, metaModelVersion ) );
+      result.assertNumberOfFiles( 8 );
+      result.assertFields( "MetaAspectWithExtendedEntity",
+            ImmutableMap.<String, Object> builder().put( "NAMESPACE", String.class ).put( "MODEL_ELEMENT_URN", String.class )
+                  .put( "CHARACTERISTIC_NAMESPACE", String.class ).put( "INSTANCE", "MetaAspectWithExtendedEntity" )
+                  .put( "TEST_PROPERTY", "StaticContainerProperty<TestEntity,java.util.LinkedHashSet<TestEntity>>").build(), new HashMap<>() );
+   }
+
    @ParameterizedTest
    @MethodSource( value = "allVersions" )
    public void testGenerateStaticMetaModelWithRecursiveAspectWithOptional( final KnownVersion metaModelVersion ) throws IOException {
@@ -211,7 +235,7 @@ ImmutableMap.<String, Object> builder().put( "NAMESPACE", String.class ).put( "M
    }
 
    @ParameterizedTest
-//   @MethodSource( value = "allVersions" )
+   //   @MethodSource( value = "allVersions" )
    @MethodSource( value = "latestVersion" )
    public void testGenerateStaticMetaModelWithConstraints( final KnownVersion metaModelVersion ) throws IOException {
       final TestAspect aspect = TestAspect.ASPECT_WITH_CONSTRAINTS;

core/sds-test-aspect-models/src/main/java/io/openmanufacturing/sds/test/TestAspect.java

@@ -94,6 +94,7 @@ public enum TestAspect implements TestModel {
    ASPECT_WITH_ERROR_COLLECTION,
    ASPECT_WITH_EVENT,
    ASPECT_WITH_EXCLUSIVE_RANGE_CONSTRAINT,
+   ASPECT_WITH_EXTENDED_ENTITY,
    ASPECT_WITH_EXTENDED_ENUMS,
    ASPECT_WITH_EXTENDED_ENUMS_WITH_NOT_IN_PAYLOAD_PROPERTY,
    ASPECT_WITH_FIXED_POINT,

core/sds-test-aspect-models/src/main/resources/valid/bamm_2_0_0/io.openmanufacturing.test/1.0.0/AspectWithExtendedEntity.ttl

@@ -0,0 +1,65 @@
+    # Copyright (c) 2021 Robert Bosch Manufacturing Solutions GmbH
+#
+# See the AUTHORS file(s) distributed with this work for additional
+# information regarding authorship.
+#
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at https://mozilla.org/MPL/2.0/.
+#
+# SPDX-License-Identifier: MPL-2.0
+
+@prefix :       <urn:bamm:io.openmanufacturing.test:1.0.0#> .
+@prefix bamm:   <urn:bamm:io.openmanufacturing:meta-model:2.0.0#> .
+@prefix bamm-c: <urn:bamm:io.openmanufacturing:characteristic:2.0.0#> .
+@prefix bamm-e: <urn:bamm:io.openmanufacturing:entity:2.0.0#> .
+@prefix unit:   <urn:bamm:io.openmanufacturing:unit:2.0.0#> .
+@prefix xsd:    <http://www.w3.org/2001/XMLSchema#> .
+
+:AspectWithExtendedEntity
+    a               bamm:Aspect ;
+    bamm:name       "AspectWithExtendedEntity" ;
+    bamm:properties ( :testProperty ) ;
+    bamm:operations ( ) .
+
+:testProperty a bamm:Property ;
+              bamm:preferredName "Test Property"@en ;
+              bamm:description "This is a test property."@en ;
+              bamm:see <http://example.com/omp> ;
+              bamm:see <http://example.com/me> ;
+              bamm:characteristic [ a             bamm-c:SortedSet ;
+                                    bamm:name     "AspectWithExtendedEntity" ;
+                                    bamm:dataType :TestEntity ] .
+
+:TestEntity
+    a               bamm:Entity ;
+    bamm:extends    :ParentTestEntity ;
+    bamm:name       "TestEntity" ;
+    bamm:properties ( ) .
+
+:ParentTestEntity
+    a               bamm:AbstractEntity ;
+    bamm:extends    :ParentOfParentEntity ;
+    bamm:name       "ParentTestEntity" ;
+    bamm:properties ( :parentString ) .
+
+:ParentOfParentEntity
+    a               bamm:AbstractEntity ;
+    bamm:name       "ParentOfParentEntity" ;
+    bamm:properties ( :parentOfParentString ) .
+
+:StringCode
+    a             bamm-c:Code ;
+    bamm:name     "StringCode" ;
+    bamm:dataType xsd:string .
+
+:parentString
+    a                   bamm:Property ;
+    bamm:name           "parentString" ;
+    bamm:characteristic :StringCode .
+
+:parentOfParentString
+    a                   bamm:Property ;
+    bamm:name           "parentOfParentString" ;
+    bamm:characteristic :StringCode .
+