Added option to not use the reflection API when encountering loaded t…

…ypes during a retransformation or redefinition of a type but rather to rely onto the type pool-generated description.

byte-buddy-dep/src/main/java/net/bytebuddy/description/type/TypeDescription.java

@@ -7283,6 +7283,22 @@ public ForLoadedType(Class<?> type) {
             this.type = type;
         }
 
+        /**
+         * Returns the type's actual name where it is taken into consideration that this type might be loaded anonymously.
+         * In this case, the remainder of the types name is suffixed by {@code /<id>} which is removed when using this method
+         * but is retained when calling {@link Class#getName()}.
+         *
+         * @param type The type for which to resolve its name.
+         * @return The type's actual name.
+         */
+        public static String getName(Class<?> type) {
+            String name = type.getName();
+            int anonymousLoaderIndex = name.indexOf('/');
+            return anonymousLoaderIndex == -1
+                    ? name
+                    : name.substring(0, anonymousLoaderIndex);
+        }
+
         @Override
         public boolean isAssignableFrom(Class<?> type) {
             // The JVM conducts more efficient assignability lookups of loaded types what is attempted first.
@@ -7429,11 +7445,7 @@ public StackSize getStackSize() {
 
         @Override
         public String getName() {
-            String name = type.getName();
-            int anonymousLoaderIndex = name.indexOf('/');
-            return anonymousLoaderIndex == -1
-                    ? name
-                    : name.substring(0, anonymousLoaderIndex);
+            return getName(type);
         }
 
         @Override

byte-buddy-dep/src/test/java/net/bytebuddy/agent/builder/AgentBuilderDefaultApplicationTest.java

@@ -217,6 +217,34 @@ public void testRedefinition() throws Exception {
         }
     }
 
+    @Test
+    @AgentAttachmentRule.Enforce(redefinesClasses = true)
+    public void testRedefinitionWithPoolOnly() throws Exception {
+        // As documented, the class loading type locator is not applicable for redefinitions.
+        if (typeLocator.equals(AgentBuilder.TypeLocator.ClassLoading.INSTANCE)) {
+            return;
+        }
+        // A redefinition reflects on loaded types which are eagerly validated types (Java 7- for redefinition).
+        // This causes type equality for outer/inner classes to fail which is whz an external class is used.
+        assertThat(ByteBuddyAgent.install(), instanceOf(Instrumentation.class));
+        assertThat(classLoader.loadClass(SimpleType.class.getName()).getName(), is(SimpleType.class.getName())); // ensure that class is loaded
+        ClassFileTransformer classFileTransformer = new AgentBuilder.Default()
+                .with(typeLocator)
+                .ignore(none())
+                .with(AgentBuilder.InitializationStrategy.NoOp.INSTANCE)
+                .with(AgentBuilder.TypeStrategy.Default.REDEFINE)
+                .with(AgentBuilder.RedefinitionStrategy.REDEFINITION)
+                .with(AgentBuilder.DescriptionStrategy.POOL_ONLY)
+                .type(isAnnotatedWith(ShouldRebase.class), ElementMatchers.is(classLoader)).transform(new FooTransformer())
+                .installOnByteBuddyAgent();
+        try {
+            Class<?> type = classLoader.loadClass(SimpleType.class.getName());
+            assertThat(type.getDeclaredMethod(FOO).invoke(type.newInstance()), is((Object) BAR));
+        } finally {
+            ByteBuddyAgent.getInstrumentation().removeTransformer(classFileTransformer);
+        }
+    }
+
     @Test
     @AgentAttachmentRule.Enforce(retransformsClasses = true)
     public void testRetransformation() throws Exception {
@@ -240,6 +268,30 @@ public void testRetransformation() throws Exception {
         }
     }
 
+    @Test
+    @AgentAttachmentRule.Enforce(retransformsClasses = true)
+    public void testRetransformationWithPoolOnly() throws Exception {
+        // A redefinition reflects on loaded types which are eagerly validated types (Java 7- for redefinition).
+        // This causes type equality for outer/inner classes to fail which is whz an external class is used.
+        assertThat(ByteBuddyAgent.install(), instanceOf(Instrumentation.class));
+        assertThat(classLoader.loadClass(SimpleType.class.getName()).getName(), is(SimpleType.class.getName())); // ensure that class is loaded
+        ClassFileTransformer classFileTransformer = new AgentBuilder.Default()
+                .with(typeLocator)
+                .ignore(none())
+                .with(AgentBuilder.InitializationStrategy.NoOp.INSTANCE)
+                .with(AgentBuilder.TypeStrategy.Default.REDEFINE)
+                .with(AgentBuilder.RedefinitionStrategy.RETRANSFORMATION)
+                .with(AgentBuilder.DescriptionStrategy.POOL_ONLY)
+                .type(isAnnotatedWith(ShouldRebase.class), ElementMatchers.is(classLoader)).transform(new FooTransformer())
+                .installOnByteBuddyAgent();
+        try {
+            Class<?> type = classLoader.loadClass(SimpleType.class.getName());
+            assertThat(type.getDeclaredMethod(FOO).invoke(type.newInstance()), is((Object) BAR));
+        } finally {
+            ByteBuddyAgent.getInstrumentation().removeTransformer(classFileTransformer);
+        }
+    }
+
     @Test
     @AgentAttachmentRule.Enforce
     public void testChainedAgent() throws Exception {

byte-buddy-dep/src/test/java/net/bytebuddy/agent/builder/AgentBuilderDefaultTest.java

@@ -1028,6 +1028,7 @@ public void testExecutingTransformerHandlesNullValue() throws Exception {
                 accessControlContext,
                 initializationStrategy,
                 mock(AgentBuilder.Default.BootstrapInjectionStrategy.class),
+                AgentBuilder.DescriptionStrategy.HYBRID,
                 mock(AgentBuilder.RawMatcher.class),
                 mock(AgentBuilder.Default.Transformation.class))
                 .transform(mock(ClassLoader.class),

byte-buddy-dep/src/test/java/net/bytebuddy/agent/builder/AgentBuilderDescriptionStrategyTest.java

@@ -0,0 +1,88 @@
+package net.bytebuddy.agent.builder;
+
+import net.bytebuddy.description.type.TypeDescription;
+import net.bytebuddy.dynamic.ClassFileLocator;
+import net.bytebuddy.pool.TypePool;
+import net.bytebuddy.test.utility.MockitoRule;
+import net.bytebuddy.test.utility.ObjectPropertyAssertion;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TestRule;
+import org.mockito.Mock;
+
+import static org.hamcrest.CoreMatchers.instanceOf;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.Is.is;
+import static org.mockito.Mockito.when;
+
+public class AgentBuilderDescriptionStrategyTest {
+
+    @Rule
+    public TestRule mockitoRule = new MockitoRule(this);
+
+    @Mock
+    private AgentBuilder.TypeLocator typeLocator;
+
+    @Mock
+    private TypePool typePool;
+
+    @Mock
+    private TypeDescription typeDescription;
+
+    @Test
+    public void testDescriptionHybridWithLoaded() throws Exception {
+        ClassFileLocator classFileLocator = ClassFileLocator.ForClassLoader.of(Object.class.getClassLoader());
+        when(typeLocator.typePool(classFileLocator, Object.class.getClassLoader())).thenReturn(typePool);
+        when(typePool.describe(Object.class.getName())).thenReturn(new TypePool.Resolution.Simple(typeDescription));
+        TypeDescription typeDescription = AgentBuilder.DescriptionStrategy.HYBRID.apply(Object.class.getName(),
+                Object.class,
+                typeLocator,
+                Object.class.getClassLoader(),
+                classFileLocator);
+        assertThat(typeDescription, is(TypeDescription.OBJECT));
+        assertThat(typeDescription, instanceOf(TypeDescription.ForLoadedType.class));
+    }
+
+    @Test
+    public void testDescriptionHybridWithoutLoaded() throws Exception {
+        ClassFileLocator classFileLocator = ClassFileLocator.ForClassLoader.of(Object.class.getClassLoader());
+        when(typeLocator.typePool(classFileLocator, Object.class.getClassLoader())).thenReturn(typePool);
+        when(typePool.describe(Object.class.getName())).thenReturn(new TypePool.Resolution.Simple(typeDescription));
+        TypeDescription typeDescription = AgentBuilder.DescriptionStrategy.HYBRID.apply(Object.class.getName(),
+                null,
+                typeLocator,
+                Object.class.getClassLoader(),
+                classFileLocator);
+        assertThat(typeDescription, is(this.typeDescription));
+    }
+
+    @Test
+    public void testDescriptionPoolOnly() throws Exception {
+        ClassFileLocator classFileLocator = ClassFileLocator.ForClassLoader.of(Object.class.getClassLoader());
+        when(typeLocator.typePool(classFileLocator, Object.class.getClassLoader())).thenReturn(typePool);
+        when(typePool.describe(Object.class.getName())).thenReturn(new TypePool.Resolution.Simple(typeDescription));
+        assertThat(AgentBuilder.DescriptionStrategy.POOL_ONLY.apply(Object.class.getName(),
+                Object.class,
+                typeLocator,
+                Object.class.getClassLoader(),
+                classFileLocator), is(typeDescription));
+    }
+
+    @Test
+    public void testLoadedDescriptionHybrid() throws Exception {
+        assertThat(AgentBuilder.DescriptionStrategy.HYBRID.apply(Object.class, typeLocator), is(TypeDescription.OBJECT));
+        assertThat(AgentBuilder.DescriptionStrategy.HYBRID.apply(Object.class, typeLocator), instanceOf(TypeDescription.ForLoadedType.class));
+    }
+
+    @Test
+    public void testLoadedDescriptionPoolOnly() throws Exception {
+        when(typeLocator.typePool(ClassFileLocator.ForClassLoader.of(Object.class.getClassLoader()), Object.class.getClassLoader())).thenReturn(typePool);
+        when(typePool.describe(Object.class.getName())).thenReturn(new TypePool.Resolution.Simple(typeDescription));
+        assertThat(AgentBuilder.DescriptionStrategy.POOL_ONLY.apply(Object.class, typeLocator), is(typeDescription));
+    }
+
+    @Test
+    public void testObjectProperties() throws Exception {
+        ObjectPropertyAssertion.of(AgentBuilder.DescriptionStrategy.class).apply();
+    }
+}

byte-buddy-dep/src/test/java/net/bytebuddy/description/type/TypeDescriptionForLoadedTypeTest.java

@@ -8,6 +8,9 @@
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.Is.is;
+
 public class TypeDescriptionForLoadedTypeTest extends AbstractTypeDescriptionTest {
 
     @Override
@@ -121,4 +124,9 @@ public void testGenericInnerTypeAnnotationReceiverTypeOnMethod() throws Exceptio
     public void testTypeAnnotationNonGenericInnerType() throws Exception {
         super.testTypeAnnotationNonGenericInnerType();
     }
+
+    @Test
+    public void testNameEqualityNonAnonymous() throws Exception {
+        assertThat(TypeDescription.ForLoadedType.getName(Object.class), is(Object.class.getName()));
+    }
 }