feat(jaxb-package): possibility to choose a JAXBContext instantiation…

… using package mode (OpenFeign#2005)

Co-authored-by: jernat <jernat.morbal@gmail.com>
Co-authored-by: Marvin Froeder <velo@users.noreply.github.com>

jaxb/src/main/java/feign/jaxb/JAXBContextCacheKey.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2012-2023 The Feign Authors
+ *
+ * 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.
+ */
+package feign.jaxb;
+
+/**
+ * Encapsulate data used to build the cache key of JAXBContext.
+ */
+interface JAXBContextCacheKey {
+}

jaxb/src/main/java/feign/jaxb/JAXBContextClassCacheKey.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2012-2023 The Feign Authors
+ *
+ * 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.
+ */
+package feign.jaxb;
+
+import java.util.Objects;
+
+/**
+ * Encapsulate data used to build the cache key of JAXBContext when created using class mode.
+ */
+final class JAXBContextClassCacheKey implements JAXBContextCacheKey {
+
+  private final Class<?> clazz;
+
+  JAXBContextClassCacheKey(Class<?> clazz) {
+    this.clazz = clazz;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o)
+      return true;
+    if (o == null || getClass() != o.getClass())
+      return false;
+    JAXBContextClassCacheKey that = (JAXBContextClassCacheKey) o;
+    return clazz.equals(that.clazz);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(clazz);
+  }
+}

jaxb/src/main/java/feign/jaxb/JAXBContextFactory.java

@@ -31,12 +31,15 @@
  */
 public final class JAXBContextFactory {
 
-  private final ConcurrentHashMap<Class<?>, JAXBContext> jaxbContexts =
+  private final ConcurrentHashMap<JAXBContextCacheKey, JAXBContext> jaxbContexts =
       new ConcurrentHashMap<>(64);
   private final Map<String, Object> properties;
+  private final JAXBContextInstantationMode jaxbContextInstantationMode;
 
-  private JAXBContextFactory(Map<String, Object> properties) {
+  private JAXBContextFactory(Map<String, Object> properties,
+      JAXBContextInstantationMode jaxbContextInstantationMode) {
     this.properties = properties;
+    this.jaxbContextInstantationMode = jaxbContextInstantationMode;
   }
 
   /**
@@ -62,10 +65,12 @@ private void setMarshallerProperties(Marshaller marshaller) throws PropertyExcep
   }
 
   private JAXBContext getContext(Class<?> clazz) throws JAXBException {
-    JAXBContext jaxbContext = this.jaxbContexts.get(clazz);
+    JAXBContextCacheKey cacheKey = jaxbContextInstantationMode.getJAXBContextCacheKey(clazz);
+    JAXBContext jaxbContext = this.jaxbContexts.get(cacheKey);
+
     if (jaxbContext == null) {
-      jaxbContext = JAXBContext.newInstance(clazz);
-      this.jaxbContexts.putIfAbsent(clazz, jaxbContext);
+      jaxbContext = jaxbContextInstantationMode.getJAXBContext(clazz);
+      this.jaxbContexts.putIfAbsent(cacheKey, jaxbContext);
     }
     return jaxbContext;
   }
@@ -91,6 +96,9 @@ public static class Builder {
 
     private final Map<String, Object> properties = new HashMap<>(10);
 
+    private JAXBContextInstantationMode jaxbContextInstantationMode =
+        JAXBContextInstantationMode.CLASS;
+
     /**
      * Sets the jaxb.encoding property of any Marshaller created by this factory.
      */
@@ -149,12 +157,31 @@ public Builder withProperty(String key, Object value) {
       return this;
     }
 
+    /**
+     * Provide an instantiation mode for JAXB Contexts, can be class or package, default is class if
+     * this method is not called.
+     *
+     * <p>
+     * Example : <br>
+     * <br>
+     * <code>
+     *    new JAXBContextFactory.Builder()
+     *      .withJAXBContextInstantiationMode(JAXBContextInstantationMode.PACKAGE)
+     *      .build();
+     * </code>
+     * </p>
+     */
+    public Builder withJAXBContextInstantiationMode(JAXBContextInstantationMode jaxbContextInstantiationMode) {
+      this.jaxbContextInstantationMode = jaxbContextInstantiationMode;
+      return this;
+    }
+
     /**
      * Creates a new {@link feign.jaxb.JAXBContextFactory} instance with a lazy loading cached
      * context
      */
     public JAXBContextFactory build() {
-      return new JAXBContextFactory(properties);
+      return new JAXBContextFactory(properties, jaxbContextInstantationMode);
     }
 
     /**
@@ -167,7 +194,7 @@ public JAXBContextFactory build() {
      *         likely due to missing JAXB annotations
      */
     public JAXBContextFactory build(List<Class<?>> classes) throws JAXBException {
-      JAXBContextFactory factory = new JAXBContextFactory(properties);
+      JAXBContextFactory factory = new JAXBContextFactory(properties, jaxbContextInstantationMode);
       factory.preloadContextCache(classes);
       return factory;
     }

jaxb/src/main/java/feign/jaxb/JAXBContextInstantationMode.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2012-2023 The Feign Authors
+ *
+ * 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.
+ */
+package feign.jaxb;
+
+import javax.xml.bind.JAXBContext;
+import javax.xml.bind.JAXBException;
+
+/**
+ * Provides differents ways to instantiate a JAXB Context.
+ */
+public enum JAXBContextInstantationMode {
+
+  CLASS {
+    @Override
+    JAXBContextCacheKey getJAXBContextCacheKey(Class<?> clazz) {
+      return new JAXBContextClassCacheKey(clazz);
+    }
+
+    @Override
+    JAXBContext getJAXBContext(Class<?> clazz) throws JAXBException {
+      return JAXBContext.newInstance(clazz);
+    }
+  },
+
+  PACKAGE {
+    @Override
+    JAXBContextCacheKey getJAXBContextCacheKey(Class<?> clazz) {
+      return new JAXBContextPackageCacheKey(clazz.getPackage().getName(), clazz.getClassLoader());
+    }
+
+    @Override
+    JAXBContext getJAXBContext(Class<?> clazz) throws JAXBException {
+      return JAXBContext.newInstance(clazz.getPackage().getName(), clazz.getClassLoader());
+    }
+  };
+
+  abstract JAXBContextCacheKey getJAXBContextCacheKey(Class<?> clazz);
+
+  abstract JAXBContext getJAXBContext(Class<?> clazz) throws JAXBException;
+}

jaxb/src/main/java/feign/jaxb/JAXBContextPackageCacheKey.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2012-2023 The Feign Authors
+ *
+ * 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.
+ */
+package feign.jaxb;
+
+import java.util.Objects;
+
+/**
+ * Encapsulate data used to build the cache key of JAXBContext when created using package mode.
+ */
+final class JAXBContextPackageCacheKey implements JAXBContextCacheKey {
+
+  private final String packageName;
+
+  private final ClassLoader classLoader;
+
+  JAXBContextPackageCacheKey(String packageName, ClassLoader classLoader) {
+    this.packageName = packageName;
+    this.classLoader = classLoader;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o)
+      return true;
+    if (o == null || getClass() != o.getClass())
+      return false;
+    JAXBContextPackageCacheKey that = (JAXBContextPackageCacheKey) o;
+    return packageName.equals(that.packageName) && classLoader.equals(that.classLoader);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(packageName, classLoader);
+  }
+}

jaxb/src/test/java/feign/jaxb/JAXBContextFactoryTest.java

@@ -13,16 +13,15 @@
  */
 package feign.jaxb;
 
+import feign.jaxb.mock.onepackage.AnotherMockedJAXBObject;
+import feign.jaxb.mock.onepackage.MockedJAXBObject;
+import org.junit.Test;
+import javax.xml.bind.Marshaller;
 import java.lang.reflect.Field;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
-import org.junit.Test;
-import javax.xml.bind.Marshaller;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.*;
 
 public class JAXBContextFactoryTest {
 
@@ -88,9 +87,65 @@ public void testPreloadCache() throws Exception {
     Map internalCache = (Map) f.get(factory); // IllegalAccessException
     assertFalse(internalCache.isEmpty());
     assertTrue(internalCache.size() == classes.size());
-    assertNotNull(internalCache.get(String.class));
-    assertNotNull(internalCache.get(Integer.class));
+    assertNotNull(internalCache.get(new JAXBContextClassCacheKey(String.class)));
+    assertNotNull(internalCache.get(new JAXBContextClassCacheKey(Integer.class)));
 
   }
 
+  @Test
+  public void testClassModeInstantiation() throws Exception {
+
+    List<Class<?>> classes = Arrays.asList(String.class, Integer.class);
+    JAXBContextFactory factory =
+        new JAXBContextFactory.Builder()
+            .withJAXBContextInstantiationMode(JAXBContextInstantationMode.CLASS)
+            .build(classes);
+
+    Field f = factory.getClass().getDeclaredField("jaxbContexts"); // NoSuchFieldException
+    f.setAccessible(true);
+    Map internalCache = (Map) f.get(factory); // IllegalAccessException
+    assertFalse(internalCache.isEmpty());
+    assertEquals(internalCache.size(), classes.size());
+    assertNotNull(internalCache.get(new JAXBContextClassCacheKey(String.class)));
+    assertNotNull(internalCache.get(new JAXBContextClassCacheKey(Integer.class)));
+
+  }
+
+  @Test
+  public void testPackageModeInstantiationUsingSamePackage() throws Exception {
+
+    JAXBContextFactory factory = new JAXBContextFactory.Builder()
+        .withJAXBContextInstantiationMode(JAXBContextInstantationMode.PACKAGE)
+        .build(Arrays.asList(MockedJAXBObject.class, AnotherMockedJAXBObject.class));
+
+    Field f = factory.getClass().getDeclaredField("jaxbContexts"); // NoSuchFieldException
+    f.setAccessible(true);
+    Map internalCache = (Map) f.get(factory); // IllegalAccessException
+    assertFalse(internalCache.isEmpty());
+    assertEquals(1, internalCache.size());
+    assertNotNull(internalCache.get(new JAXBContextPackageCacheKey("feign.jaxb.mock.onepackage",
+        AnotherMockedJAXBObject.class.getClassLoader())));
+
+  }
+
+  @Test
+  public void testPackageModeInstantiationUsingMultiplePackages() throws Exception {
+
+    JAXBContextFactory factory = new JAXBContextFactory.Builder()
+        .withJAXBContextInstantiationMode(JAXBContextInstantationMode.PACKAGE)
+        .build(Arrays.asList(MockedJAXBObject.class,
+            feign.jaxb.mock.anotherpackage.MockedJAXBObject.class));
+
+    Field f = factory.getClass().getDeclaredField("jaxbContexts"); // NoSuchFieldException
+    f.setAccessible(true);
+    Map internalCache = (Map) f.get(factory); // IllegalAccessException
+    assertFalse(internalCache.isEmpty());
+    assertEquals(2, internalCache.size());
+    assertNotNull(internalCache.get(new JAXBContextPackageCacheKey("feign.jaxb.mock.onepackage",
+        MockedJAXBObject.class.getClassLoader())));
+    assertNotNull(internalCache.get(new JAXBContextPackageCacheKey("feign.jaxb.mock.anotherpackage",
+        feign.jaxb.mock.anotherpackage.MockedJAXBObject.class.getClassLoader())));
+
+
+  }
 }

jaxb/src/test/java/feign/jaxb/mock/anotherpackage/MockedJAXBObject.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2012-2023 The Feign Authors
+ *
+ * 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.
+ */
+package feign.jaxb.mock.anotherpackage;
+
+import javax.xml.bind.annotation.XmlRootElement;
+
+@XmlRootElement(name = "anothertest")
+public class MockedJAXBObject {
+}

jaxb/src/test/java/feign/jaxb/mock/anotherpackage/ObjectFactory.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2012-2023 The Feign Authors
+ *
+ * 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.
+ */
+package feign.jaxb.mock.anotherpackage;
+
+import javax.xml.bind.annotation.XmlRegistry;
+
+@XmlRegistry
+public class ObjectFactory {
+
+  public MockedJAXBObject createMockedJAXBObject() {
+    return new MockedJAXBObject();
+  }
+}