Make CritterClassLoader accept a ClassLoader from MorphiaConfig

core/src/main/java/dev/morphia/config/ManualMorphiaConfig.java

@@ -35,6 +35,7 @@ public class ManualMorphiaConfig implements MorphiaConfig {
     Boolean applyCaps;
     Boolean applyDocumentValidations;
     Boolean applyIndexes;
+    ClassLoader classLoader;
 
     Optional<CodecProvider> codecProvider;
 
@@ -69,6 +70,7 @@ public ManualMorphiaConfig(MorphiaConfig base) {
         applyCaps = base.applyCaps();
         applyDocumentValidations = base.applyDocumentValidations();
         applyIndexes = base.applyIndexes();
+        classLoader = base.classLoader();
         codecProvider = base.codecProvider();
         collectionNaming = base.collectionNaming();
         database = base.database();
@@ -122,6 +124,11 @@ public Boolean applyCaps() {
         return orDefault(applyCaps, FALSE);
     }
 
+    @Override
+    public ClassLoader classLoader() {
+        return orDefault(classLoader, Thread.currentThread().getContextClassLoader());
+    }
+
     public Boolean applyDocumentValidations() {
         return orDefault(applyDocumentValidations, FALSE);
     }

core/src/main/java/dev/morphia/config/MorphiaConfig.java

@@ -48,6 +48,30 @@
 @ConfigMapping(prefix = "morphia")
 public interface MorphiaConfig {
 
+    /**
+     * The classloader to use for class lookups and bytecode generation.
+     *
+     * @return the configured classloader
+     * @since 3.0
+     */
+    default ClassLoader classLoader() {
+        return Thread.currentThread().getContextClassLoader();
+    }
+
+    /**
+     * Updates this configuration with a new value and returns a new instance. The original instance is unchanged.
+     *
+     * @param value the new value
+     * @return a new instance with the updated configuration
+     * @since 3.0
+     */
+    default MorphiaConfig classLoader(ClassLoader value) {
+        var newConfig = new ManualMorphiaConfig(this);
+
+        newConfig.classLoader = value;
+        return newConfig;
+    }
+
     /**
      * Tries to load a configuration from the default location.
      * 

core/src/main/java/dev/morphia/critter/CritterClassLoader.java

@@ -12,10 +12,6 @@ public CritterClassLoader(ClassLoader parent) {
         super(parent, Collections.emptyMap());
     }
 
-    public CritterClassLoader() {
-        this(Thread.currentThread().getContextClassLoader());
-    }
-
     public void register(String name, byte[] bytes) {
         typeDefinitions.put(name, bytes);
     }

core/src/main/java/dev/morphia/mapping/AbstractMapper.java

@@ -64,7 +64,7 @@ public abstract class AbstractMapper implements Mapper {
     @MorphiaInternal
     protected AbstractMapper(MorphiaConfig config) {
         this.config = config;
-        this.contextClassLoader = Thread.currentThread().getContextClassLoader();
+        this.contextClassLoader = config.classLoader();
         this.discriminatorLookup = new DiscriminatorLookup();
     }
 

core/src/test/java/dev/morphia/critter/parser/GeneratorTest.java

@@ -23,7 +23,7 @@
 
 public class GeneratorTest {
     public static final CritterEntityModel entityModel;
-    public static final CritterClassLoader critterClassLoader = new CritterClassLoader();
+    public static final CritterClassLoader critterClassLoader = new CritterClassLoader(Thread.currentThread().getContextClassLoader());
 
     static {
         ClassGraph classGraph = new ClassGraph()

core/src/test/java/dev/morphia/critter/parser/TestAccessorsMutators.java

@@ -11,7 +11,7 @@
 import org.testng.annotations.DataProvider;
 
 public class TestAccessorsMutators extends BaseCritterTest {
-    private final CritterClassLoader critterClassLoader = new CritterClassLoader();
+    private final CritterClassLoader critterClassLoader = new CritterClassLoader(Thread.currentThread().getContextClassLoader());
 
     // @Test(dataProvider = "classes")
     public void testPropertyAccessors(Class<?> type) throws Exception {

core/src/test/java/dev/morphia/critter/parser/TestEntityModelGenerator.java

@@ -20,7 +20,7 @@ public class TestEntityModelGenerator {
 
     private final CritterEntityModel control;
     private final Mapper mapper = new ReflectiveMapper(new ManualMorphiaConfig());
-    private final CritterClassLoader critterClassLoader = new CritterClassLoader();
+    private final CritterClassLoader critterClassLoader = new CritterClassLoader(Thread.currentThread().getContextClassLoader());
 
     public TestEntityModelGenerator() {
         CritterEntityModel tmp;

core/src/test/java/dev/morphia/critter/parser/TestPropertyModelGenerator.java

@@ -14,7 +14,7 @@
 import org.testng.annotations.NoInjection;
 
 public class TestPropertyModelGenerator extends BaseCritterTest {
-    private final CritterClassLoader critterClassLoader = new CritterClassLoader();
+    private final CritterClassLoader critterClassLoader = new CritterClassLoader(Thread.currentThread().getContextClassLoader());
 
     // @Test(dataProvider = "properties", testName = "")
     public void testProperty(String control, String methodName, @NoInjection Method method) throws Exception {

core/src/test/java/dev/morphia/critter/parser/TestVarHandleAccessor.java

@@ -22,7 +22,7 @@ public class TestVarHandleAccessor {
 
     @BeforeClass
     public void setup() {
-        classLoader = new CritterClassLoader();
+        classLoader = new CritterClassLoader(Thread.currentThread().getContextClassLoader());
         MorphiaConfig config = new ManualMorphiaConfig();
         CritterGizmoGenerator.generate(Example.class, classLoader, new Generators(config, new ReflectiveMapper(config)), true);
     }

core/src/test/java/dev/morphia/critter/parser/gizmo/TestGizmoGeneration.java

@@ -48,7 +48,7 @@
 import static io.quarkus.gizmo.MethodDescriptor.ofMethod;
 
 public class TestGizmoGeneration {
-    private final CritterClassLoader critterClassLoader = new CritterClassLoader();
+    private final CritterClassLoader critterClassLoader = new CritterClassLoader(Thread.currentThread().getContextClassLoader());
 
     @Test
     public void testMapStringExample() {
@@ -262,7 +262,7 @@ public void testConstructors() throws Exception {
 
     @Test
     public void testMethodBasedAccessors() throws Exception {
-        CritterClassLoader classLoader = new CritterClassLoader();
+        CritterClassLoader classLoader = new CritterClassLoader(Thread.currentThread().getContextClassLoader());
 
         String resourceName = MethodExample.class.getName().replace('.', '/') + ".class";
         var inputStream = MethodExample.class.getClassLoader().getResourceAsStream(resourceName);