Improve coverage on apex-pdp

Issue-ID: POLICY-5059
Signed-off-by: rameshiyer27 <ramesh.murugan.iyer@est.tech>
Change-Id: I3d8d71f4ee9db10fe43bfe51586156cf768a8560

7 files changed, 444 insertions, 1 deletions

diff --git a/plugins/plugins-context/plugins-context-distribution/plugins-context-distribution-hazelcast/src/test/java/org/onap/policy/apex/plugins/context/distribution/hazelcast/HazelCastDistributorTest.java b/plugins/plugins-context/plugins-context-distribution/plugins-context-distribution-hazelcast/src/test/java/org/onap/policy/apex/plugins/context/distribution/hazelcast/HazelCastDistributorTest.java
new file mode 100644
index 000000000..6db3084d8
--- /dev/null
+++ b/plugins/plugins-context/plugins-context-distribution/plugins-context-distribution-hazelcast/src/test/java/org/onap/policy/apex/plugins/context/distribution/hazelcast/HazelCastDistributorTest.java
@@ -0,0 +1,72 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2024 Nordix Foundation. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.plugins.context.distribution.hazelcast;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.onap.policy.apex.context.ContextException;
+import org.onap.policy.apex.context.parameters.ContextParameterConstants;
+import org.onap.policy.apex.context.parameters.ContextParameters;
+import org.onap.policy.apex.model.basicmodel.concepts.AxArtifactKey;
+import org.onap.policy.common.parameters.ParameterService;
+
+
+class HazelCastDistributorTest {
+
+    @BeforeAll
+    public static void prepareForTest() {
+        final ContextParameters contextParameters = new ContextParameters();
+        contextParameters.getLockManagerParameters()
+                .setPluginClass("org.onap.policy.apex.context.impl.locking.jvmlocal.JvmLocalLockManager");
+
+        contextParameters.setName(ContextParameterConstants.MAIN_GROUP_NAME);
+        contextParameters.getLockManagerParameters().setName(ContextParameterConstants.LOCKING_GROUP_NAME);
+        contextParameters.getPersistorParameters().setName(ContextParameterConstants.PERSISTENCE_GROUP_NAME);
+
+        ParameterService.register(contextParameters);
+        ParameterService.register(contextParameters.getLockManagerParameters());
+        ParameterService.register(contextParameters.getPersistorParameters());
+    }
+
+    /**
+     * Clear down the test data.
+     */
+    @AfterAll
+    public static void cleanUpAfterTest() {
+        ParameterService.deregister(ContextParameterConstants.LOCKING_GROUP_NAME);
+        ParameterService.deregister(ContextParameterConstants.PERSISTENCE_GROUP_NAME);
+        ParameterService.deregister(ContextParameterConstants.MAIN_GROUP_NAME);
+        ParameterService.clear();
+    }
+
+    @Test
+    void testHazelcastDistributor() throws ContextException {
+        var distributor = new HazelcastContextDistributor();
+        var key = new AxArtifactKey("dummyKey", "1.0.1");
+        assertDoesNotThrow(() -> distributor.init(new AxArtifactKey("dummyKey", "1.0.1")));
+        assertDoesNotThrow(() -> distributor.getContextAlbumMap(key).values());
+        assertDoesNotThrow(distributor::shutdown);
+    }
+
+}
diff --git a/plugins/plugins-context/plugins-context-distribution/plugins-context-distribution-infinispan/src/main/java/org/onap/policy/apex/plugins/context/distribution/infinispan/InfinispanManager.java b/plugins/plugins-context/plugins-context-distribution/plugins-context-distribution-infinispan/src/main/java/org/onap/policy/apex/plugins/context/distribution/infinispan/InfinispanManager.java
index a9346bcc3..05d7cefb6 100644
--- a/plugins/plugins-context/plugins-context-distribution/plugins-context-distribution-infinispan/src/main/java/org/onap/policy/apex/plugins/context/distribution/infinispan/InfinispanManager.java
+++ b/plugins/plugins-context/plugins-context-distribution/plugins-context-distribution-infinispan/src/main/java/org/onap/policy/apex/plugins/context/distribution/infinispan/InfinispanManager.java
@@ -2,6 +2,7 @@
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
  *  Modifications Copyright (C) 2021 AT&T Intellectual Property. All rights reserved.
+ *  Modifications Copyright (C) 2024 Nordix Foundation.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -59,7 +60,7 @@ public class InfinispanManager {
         } catch (final IOException ioException) {
             final String errorMessage = "failed to start infinispan cache manager, "
                             + "no infinispan configuration found on local file system or in classpath, "
-                            + "try setting Infinspan \"configFile\" parameter";
+                            + "try setting Infinispan \"configFile\" parameter";
             LOGGER.error(errorMessage);
             throw new ContextException(errorMessage, ioException);
         } catch (final Exception e) {
diff --git a/plugins/plugins-context/plugins-context-distribution/plugins-context-distribution-infinispan/src/test/java/org/onap/policy/apex/plugins/context/distribution/infinispan/InfinispanDistributorTest.java b/plugins/plugins-context/plugins-context-distribution/plugins-context-distribution-infinispan/src/test/java/org/onap/policy/apex/plugins/context/distribution/infinispan/InfinispanDistributorTest.java
new file mode 100644
index 000000000..4a87b5410
--- /dev/null
+++ b/plugins/plugins-context/plugins-context-distribution/plugins-context-distribution-infinispan/src/test/java/org/onap/policy/apex/plugins/context/distribution/infinispan/InfinispanDistributorTest.java
@@ -0,0 +1,77 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2024 Nordix Foundation. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.plugins.context.distribution.infinispan;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.onap.policy.apex.context.ContextException;
+import org.onap.policy.apex.context.parameters.ContextParameterConstants;
+import org.onap.policy.apex.context.parameters.ContextParameters;
+import org.onap.policy.apex.model.basicmodel.concepts.AxArtifactKey;
+import org.onap.policy.common.parameters.ParameterService;
+
+
+class InfinispanDistributorTest {
+
+    private static InfinispanDistributorParameters distributorParams;
+
+    @BeforeAll
+    static void prepareForTest() {
+        final ContextParameters contextParameters = new ContextParameters();
+
+        contextParameters.setName(ContextParameterConstants.MAIN_GROUP_NAME);
+        contextParameters.getLockManagerParameters().setName(ContextParameterConstants.LOCKING_GROUP_NAME);
+        contextParameters.getPersistorParameters().setName(ContextParameterConstants.PERSISTENCE_GROUP_NAME);
+
+        ParameterService.register(contextParameters);
+        ParameterService.register(contextParameters.getLockManagerParameters());
+        ParameterService.register(contextParameters.getPersistorParameters());
+
+        distributorParams = new InfinispanDistributorParameters();
+        ParameterService.register(distributorParams);
+    }
+
+    /**
+     * Clear down the test data.
+     */
+    @AfterAll
+    static void cleanUpAfterTest() {
+        ParameterService.deregister(ContextParameterConstants.LOCKING_GROUP_NAME);
+        ParameterService.deregister(ContextParameterConstants.PERSISTENCE_GROUP_NAME);
+        ParameterService.clear();
+    }
+
+    @Test
+    void testInvalidParameters() throws ContextException {
+        var infiniSpanDistributor = new InfinispanContextDistributor();
+        var key = new AxArtifactKey("test", "1.1.1");
+        assertThatThrownBy(() -> infiniSpanDistributor.init(key)).isInstanceOf(NoClassDefFoundError.class)
+                .hasMessageContaining("TransactionManager");
+        assertThatThrownBy(() -> infiniSpanDistributor.getContextAlbumMap(key))
+                .hasMessageContaining("infinispanManager\" is null");
+        assertDoesNotThrow(infiniSpanDistributor::shutdown);
+    }
+
+}
diff --git a/plugins/plugins-context/plugins-context-locking/plugins-context-locking-curator/src/test/java/org/onap/policy/apex/plugins/context/locking/curator/CuratorLockFacadeTest.java b/plugins/plugins-context/plugins-context-locking/plugins-context-locking-curator/src/test/java/org/onap/policy/apex/plugins/context/locking/curator/CuratorLockFacadeTest.java
new file mode 100644
index 000000000..e4d7d6608
--- /dev/null
+++ b/plugins/plugins-context/plugins-context-locking/plugins-context-locking-curator/src/test/java/org/onap/policy/apex/plugins/context/locking/curator/CuratorLockFacadeTest.java
@@ -0,0 +1,66 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2024 Nordix Foundation. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.plugins.context.locking.curator;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.doNothing;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.mock;
+
+import java.util.concurrent.TimeUnit;
+import org.apache.curator.framework.recipes.locks.InterProcessMutex;
+import org.junit.jupiter.api.Test;
+
+class CuratorLockFacadeTest {
+
+    @Test
+    void testLock() throws Exception {
+        var mutex = mock(InterProcessMutex.class);
+        var curatorLockFacade = new CuratorLockFacade(mutex, "test");
+        assertDoesNotThrow(curatorLockFacade::lock);
+        doThrow(new RuntimeException()).when(mutex).acquire();
+        assertDoesNotThrow(curatorLockFacade::lock);
+        assertDoesNotThrow(curatorLockFacade::lockInterruptibly);
+        assertFalse(curatorLockFacade.tryLock());
+        doNothing().when(mutex).acquire();
+        assertTrue(curatorLockFacade.tryLock());
+    }
+
+    @Test
+    void testLockWithTime() throws Exception {
+        var mutex = mock(InterProcessMutex.class);
+        var curatorLockFacade = new CuratorLockFacade(mutex, "test");
+        assertTrue(curatorLockFacade.tryLock(2L, TimeUnit.MILLISECONDS));
+
+        doThrow(new RuntimeException()).when(mutex).acquire(2L, TimeUnit.MILLISECONDS);
+        assertFalse(curatorLockFacade.tryLock(2L, TimeUnit.MILLISECONDS));
+
+        assertDoesNotThrow(curatorLockFacade::unlock);
+        doThrow(new RuntimeException()).when(mutex).release();
+        assertDoesNotThrow(curatorLockFacade::unlock);
+
+        assertNull(curatorLockFacade.newCondition());
+    }
+
+}
diff --git a/plugins/plugins-context/plugins-context-locking/plugins-context-locking-curator/src/test/java/org/onap/policy/apex/plugins/context/locking/curator/CuratorLockManagerTest.java b/plugins/plugins-context/plugins-context-locking/plugins-context-locking-curator/src/test/java/org/onap/policy/apex/plugins/context/locking/curator/CuratorLockManagerTest.java
new file mode 100644
index 000000000..7ff1c5e46
--- /dev/null
+++ b/plugins/plugins-context/plugins-context-locking/plugins-context-locking-curator/src/test/java/org/onap/policy/apex/plugins/context/locking/curator/CuratorLockManagerTest.java
@@ -0,0 +1,109 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2024 Nordix Foundation. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.plugins.context.locking.curator;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.mock;
+
+import org.apache.curator.framework.CuratorFramework;
+import org.junit.jupiter.api.Test;
+import org.onap.policy.apex.context.ContextException;
+import org.onap.policy.apex.context.parameters.ContextParameterConstants;
+import org.onap.policy.apex.context.parameters.LockManagerParameters;
+import org.onap.policy.apex.model.basicmodel.concepts.AxArtifactKey;
+import org.onap.policy.common.parameters.ParameterService;
+
+
+class CuratorLockManagerTest {
+
+    @Test
+    void testLockManagerInvalidParameter() throws ContextException {
+        var manager = new CuratorLockManager();
+        var key = new AxArtifactKey("test", "1.0.1");
+
+        var parameters = new LockManagerParameters();
+        parameters.setName(ContextParameterConstants.LOCKING_GROUP_NAME);
+        ParameterService.register(parameters);
+
+        assertThatThrownBy(() -> manager.init(key)).isInstanceOf(ContextException.class)
+                .hasMessageContaining("curator lock manager parameters are not set");
+
+        ParameterService.deregister(ContextParameterConstants.LOCKING_GROUP_NAME);
+        ParameterService.clear();
+    }
+
+    @Test
+    void testLockManagerValidParams() throws ContextException {
+        var manager = new CuratorLockManager();
+        var key = new AxArtifactKey("test", "1.0.1");
+        var params = new CuratorLockManagerParameters();
+        params.setName(ContextParameterConstants.LOCKING_GROUP_NAME);
+        ParameterService.register(params);
+
+        assertThatThrownBy(() -> manager.init(key)).isInstanceOf(ContextException.class)
+                .hasMessageContaining("could not connect to Zookeeper server");
+
+        ParameterService.deregister(ContextParameterConstants.LOCKING_GROUP_NAME);
+        ParameterService.clear();
+    }
+
+    @Test
+    void testNullZookeeperAddr() throws ContextException {
+        var params = new CuratorLockManagerParameters();
+        params.setName(ContextParameterConstants.LOCKING_GROUP_NAME);
+        params.setZookeeperAddress("");
+        ParameterService.register(params);
+
+        var manager = new CuratorLockManager();
+        var key = new AxArtifactKey("test", "1.0.1");
+
+        assertThatThrownBy(() -> manager.init(key)).isInstanceOf(ContextException.class)
+                .hasMessageContaining("check if the curator Zookeeper address parameter is set correctly");
+
+        assertThatThrownBy(() -> manager.getReentrantReadWriteLock("test")).isInstanceOf(ContextException.class)
+                .hasMessageContaining("creation of lock using Zookeeper server at \"\", failed");
+
+        assertDoesNotThrow(manager::shutdown);
+
+        ParameterService.deregister(ContextParameterConstants.LOCKING_GROUP_NAME);
+        ParameterService.clear();
+    }
+
+    @Test
+    void testLockManagerParameters() {
+        var params = new CuratorLockManagerParameters();
+        assertDoesNotThrow(params::toString);
+        assertEquals("localhost:2181", params.getZookeeperAddress());
+        assertEquals(1000, params.getZookeeperConnectSleepTime());
+        assertEquals(3, params.getZookeeperContextRetries());
+    }
+
+    @Test
+    void testReentrantReadWriteLock() {
+        var curatorLock = new CuratorReentrantReadWriteLock(mock(CuratorFramework.class), "/test");
+        assertEquals("/test", curatorLock.getLockId());
+        assertDoesNotThrow(curatorLock::readLock);
+        assertDoesNotThrow(curatorLock::writeLock);
+    }
+
+}
diff --git a/plugins/plugins-context/plugins-context-schema/plugins-context-schema-avro/src/test/java/org/onap/policy/apex/plugins/context/schema/avro/AvroNullableMapperTest.java b/plugins/plugins-context/plugins-context-schema/plugins-context-schema-avro/src/test/java/org/onap/policy/apex/plugins/context/schema/avro/AvroNullableMapperTest.java
new file mode 100644
index 000000000..27a0ca3bf
--- /dev/null
+++ b/plugins/plugins-context/plugins-context-schema/plugins-context-schema-avro/src/test/java/org/onap/policy/apex/plugins/context/schema/avro/AvroNullableMapperTest.java
@@ -0,0 +1,58 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2024 Nordix Foundation. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.plugins.context.schema.avro;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.mockito.Mockito.mock;
+
+import org.apache.avro.Schema;
+import org.junit.jupiter.api.Test;
+import org.onap.policy.apex.context.ContextRuntimeException;
+import org.onap.policy.apex.model.basicmodel.concepts.ApexRuntimeException;
+import org.onap.policy.apex.model.basicmodel.concepts.AxArtifactKey;
+
+class AvroNullableMapperTest {
+
+    @Test
+    void avroNullableMapperTests() {
+        var avroObjectMapper = new AvroDirectObjectMapper();
+        var avroNullableMapper = new AvroNullableMapper(avroObjectMapper);
+        assertDoesNotThrow(() -> avroNullableMapper.init(new AxArtifactKey("test", "1.0.1"),
+                Schema.Type.BOOLEAN));
+
+        assertEquals("class java.lang.Boolean", avroNullableMapper.getJavaClass().toString());
+        assertThat(avroNullableMapper.getAvroType()).isEqualByComparingTo(Schema.Type.UNION);
+
+        var avroObjMapper = new AvroDirectObjectMapper();
+        avroObjMapper.init(new AxArtifactKey("test2", "1.1.2"), Schema.Type.BOOLEAN);
+        assertThrows(ContextRuntimeException.class, () -> avroNullableMapper.mapFromAvro(avroObjMapper));
+        assertNull(avroNullableMapper.mapFromAvro(null));
+
+        assertNull(avroNullableMapper.mapToAvro(null));
+        assertThrows(ApexRuntimeException.class, () -> avroNullableMapper.mapToAvro(avroObjMapper));
+
+        assertDoesNotThrow(() -> avroNullableMapper.createNewInstance(mock(Schema.class)));
+    }
+}
diff --git a/plugins/plugins-context/plugins-context-schema/plugins-context-schema-avro/src/test/java/org/onap/policy/apex/plugins/context/schema/avro/AvroObjMapperFactoryTest.java b/plugins/plugins-context/plugins-context-schema/plugins-context-schema-avro/src/test/java/org/onap/policy/apex/plugins/context/schema/avro/AvroObjMapperFactoryTest.java
new file mode 100644
index 000000000..4ac7a20be
--- /dev/null
+++ b/plugins/plugins-context/plugins-context-schema/plugins-context-schema-avro/src/test/java/org/onap/policy/apex/plugins/context/schema/avro/AvroObjMapperFactoryTest.java
@@ -0,0 +1,60 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2024 Nordix Foundation. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.plugins.context.schema.avro;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import java.util.List;
+import org.apache.avro.Schema;
+import org.junit.jupiter.api.Test;
+import org.onap.policy.apex.context.ContextRuntimeException;
+import org.onap.policy.apex.model.basicmodel.concepts.AxArtifactKey;
+
+class AvroObjMapperFactoryTest {
+    @Test
+    void testObjMapperFactory() {
+        var objMapperFactory = new AvroObjectMapperFactory();
+        var key = new AxArtifactKey("test", "1.0.1");
+        var schema1 = Schema.createUnion(List.of(Schema.create(Schema.Type.NULL)));
+        assertThatThrownBy(() -> objMapperFactory.get(key, schema1))
+                .isInstanceOf(ContextRuntimeException.class)
+                .hasMessageContaining("Apex currently only supports UNION schemas with 2 options, "
+                        + "one must be NULL");
+
+        var schema2 = mock(Schema.class);
+        when(schema2.getType()).thenReturn(Schema.Type.UNION);
+        var nullSchema = Schema.create(Schema.Type.NULL);
+        when(schema2.getTypes()).thenReturn(List.of(nullSchema, nullSchema));
+        assertThatThrownBy(() -> objMapperFactory.get(key, schema2))
+                .isInstanceOf(ContextRuntimeException.class)
+                .hasMessageContaining("Apex currently only supports UNION schema2 with 2 options, "
+                        + "only one can be NULL, and the other cannot be another UNION");
+
+        var fixedSchema = Schema.createFixed("test1", "doc", "test", 2);
+        when(schema2.getTypes()).thenReturn(List.of(fixedSchema, nullSchema));
+        assertDoesNotThrow(() -> objMapperFactory.get(key, schema2));
+
+    }
+
+}