Add class file locator abstraction to dynamic types. Allow explicit t…

…ype injection from build plugins.

byte-buddy-dep/src/main/java/net/bytebuddy/build/Plugin.java

@@ -97,6 +97,20 @@ interface WithPreprocessor extends Plugin {
  void onPreprocess(TypeDescription typeDescription, ClassFileLocator classFileLocator);
  }
 
+ /**
+ * Allows for the generation of types before a plugin is applied.
+ */
+ interface WithInitialization extends Plugin {
+
+ /**
+ * Returns a mapping of classes that should be created before discovering any types.
+ *
+ * @param classFileLocator A class file locator that can locate other types in the scope of the project.
+ * @return A mapping of types to their binary representation.
+ */
+ Map<TypeDescription, byte[]> initialize(ClassFileLocator classFileLocator);
+ }
+
  /**
  * A factory for providing a build plugin.
  */
@@ -110,7 +124,7 @@ interface Factory {
  Plugin make();
 
  /**
- * A simple factory that returns a preconstructed plugin instance..
+ * A simple factory that returns a preconstructed plugin instance.
  */
  @HashCodeAndEqualsPlugin.Enhance
  class Simple implements Factory {
@@ -4476,6 +4490,7 @@ public Summary apply(Source source, Target target, List<? extends Plugin.Factory
  List<String> unresolved = new ArrayList<String>();
  Throwable rethrown = null;
  List<Plugin> plugins = new ArrayList<Plugin>(factories.size());
+ List<WithInitialization> initializers = new ArrayList<WithInitialization>();
  List<WithPreprocessor> preprocessors = new ArrayList<WithPreprocessor>();
  try {
  for (Plugin.Factory factory : factories) {
@@ -4484,6 +4499,9 @@ public Summary apply(Source source, Target target, List<? extends Plugin.Factory
  if (plugin instanceof WithPreprocessor) {
  preprocessors.add((WithPreprocessor) plugin);
  }
+ if (plugin instanceof WithInitialization) {
+ initializers.add((WithInitialization) plugin);
+ }
  }
  Source.Origin origin = source.read();
  try {
@@ -4493,6 +4511,9 @@ public Summary apply(Source source, Target target, List<? extends Plugin.Factory
  listener.onManifest(manifest);
  Target.Sink sink = target.write(manifest);
  try {
+ for (WithInitialization initializer : initializers) {
+ sink.store(initializer.initialize(classFileLocator));
+ }
  Dispatcher dispatcher = dispatcherFactory.make(sink, transformed, failed, unresolved);
  try {
  for (Source.Element element : origin) {

byte-buddy-dep/src/main/java/net/bytebuddy/dynamic/DynamicType.java

@@ -59,7 +59,7 @@
  * Note that the {@link TypeDescription}s will represent their
  * unloaded forms and therefore differ from the loaded types, especially with regards to annotations.
  */
-public interface DynamicType {
+public interface DynamicType extends ClassFileLocator {
 
  /**
  * <p>
@@ -5922,6 +5922,26 @@ public Default(TypeDescription typeDescription,
  this.auxiliaryTypes = auxiliaryTypes;
  }
 
+ /**
+ * {@inheritDoc}
+ */
+ public Resolution locate(String name) throws IOException {
+ if (typeDescription.getName().equals(name)) {
+ return new Resolution.Explicit(binaryRepresentation);
+ }
+ for (DynamicType auxiliaryType : auxiliaryTypes) {
+ Resolution resolution = auxiliaryType.locate(name);
+ if (resolution.isResolved()) {
+ return resolution;
+ }
+ }
+ return new Resolution.Illegal(name);
+ }
+
+ public void close() {
+ /* do nothing */
+ }
+
  /**
  * {@inheritDoc}
  */

byte-buddy-dep/src/test/java/net/bytebuddy/build/PluginEngineDefaultTest.java

@@ -24,6 +24,7 @@
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Map;
 import java.util.jar.*;
 
 import static net.bytebuddy.test.utility.FieldByFieldComparison.hasPrototype;
@@ -83,6 +84,35 @@ public void testSimpleTransformation() throws Exception {
  verifyNoMoreInteractions(listener);
  }
 
+ @Test
+ public void testSimpleTransformationWithInitialization() throws Exception {
+ Plugin.Engine.Listener listener = mock(Plugin.Engine.Listener.class);
+ Plugin plugin = eager
+ ? new InitializingPlugin(new SimplePlugin())
+ : new PreprocessingPlugin(new InitializingPlugin(new SimplePlugin()));
+ Plugin.Engine.Source source = Plugin.Engine.Source.InMemory.ofTypes(Sample.class);
+ Plugin.Engine.Target.InMemory target = new Plugin.Engine.Target.InMemory();
+ Plugin.Engine.Summary summary = new Plugin.Engine.Default()
+ .with(listener)
+ .with(ClassFileLocator.ForClassLoader.of(SimplePlugin.class.getClassLoader()))
+ .with(dispatcherFactory)
+ .apply(source, target, new Plugin.Factory.Simple(plugin));
+ ClassLoader classLoader = new ByteArrayClassLoader(ClassLoadingStrategy.BOOTSTRAP_LOADER, target.toTypeMap());
+ Class<?> type = classLoader.loadClass(Sample.class.getName());
+ assertThat(type.getDeclaredField(FOO).getType(), is((Object) Void.class));
+ Class<?> otherType = classLoader.loadClass(OtherSample.class.getName());
+ assertThat(otherType.getDeclaredFields().length, is(0));
+ assertThat(summary.getTransformed(), hasItems(TypeDescription.ForLoadedType.of(Sample.class)));
+ assertThat(summary.getFailed().size(), is(0));
+ assertThat(summary.getUnresolved().size(), is(0));
+ verify(listener).onManifest(Plugin.Engine.Source.Origin.NO_MANIFEST);
+ verify(listener).onDiscovery(Sample.class.getName());
+ verify(listener).onTransformation(TypeDescription.ForLoadedType.of(Sample.class), plugin);
+ verify(listener).onTransformation(TypeDescription.ForLoadedType.of(Sample.class), Collections.singletonList(plugin));
+ verify(listener).onComplete(TypeDescription.ForLoadedType.of(Sample.class));
+ verifyNoMoreInteractions(listener);
+ }
+
  @Test
  public void testSimpleTransformationIgnoredByPlugin() throws Exception {
  Plugin.Engine.Listener listener = mock(Plugin.Engine.Listener.class);
@@ -378,6 +408,10 @@ private static class Sample {
  /* empty */
  }
 
+ private static class OtherSample {
+ /* empty */
+ }
+
  private static class SimplePlugin implements Plugin {
 
  public DynamicType.Builder<?> apply(DynamicType.Builder<?> builder, TypeDescription typeDescription, ClassFileLocator classFileLocator) {
@@ -452,7 +486,7 @@ public void close() {
  }
  }
 
- private static class PreprocessingPlugin implements Plugin.WithPreprocessor {
+ private static class PreprocessingPlugin implements Plugin.WithPreprocessor, Plugin.WithInitialization {
 
  private final Plugin plugin;
 
@@ -464,6 +498,39 @@ public void onPreprocess(TypeDescription typeDescription, ClassFileLocator class
  /* empty */
  }
 
+ public Map<TypeDescription, byte[]> initialize(ClassFileLocator classFileLocator) {
+ if (plugin instanceof WithInitialization) {
+ return ((WithInitialization) plugin).initialize(classFileLocator);
+ } else {
+ return Collections.emptyMap();
+ }
+ }
+
+ public DynamicType.Builder<?> apply(DynamicType.Builder<?> builder, TypeDescription typeDescription, ClassFileLocator classFileLocator) {
+ return plugin.apply(builder, typeDescription, classFileLocator);
+ }
+
+ public boolean matches(TypeDescription target) {
+ return plugin.matches(target);
+ }
+
+ public void close() throws IOException {
+ plugin.close();
+ }
+ }
+
+ private static class InitializingPlugin implements Plugin.WithInitialization {
+
+ private final Plugin plugin;
+
+ private InitializingPlugin(Plugin plugin) {
+ this.plugin = plugin;
+ }
+
+ public Map<TypeDescription, byte[]> initialize(ClassFileLocator classFileLocator) {
+ return Collections.singletonMap(TypeDescription.ForLoadedType.of(OtherSample.class), ClassFileLocator.ForClassLoader.read(OtherSample.class));
+ }
+
  public DynamicType.Builder<?> apply(DynamicType.Builder<?> builder, TypeDescription typeDescription, ClassFileLocator classFileLocator) {
  return plugin.apply(builder, typeDescription, classFileLocator);
  }

byte-buddy-dep/src/test/java/net/bytebuddy/dynamic/DynamicTypeDefaultTest.java

@@ -324,4 +324,11 @@ public void testIterationOrder() throws Exception {
  assertThat(types.next(), is(auxiliaryTypeDescription));
  assertThat(types.hasNext(), is(false));
  }
+
+ @Test
+ public void testClassFileLocator() throws Exception {
+ assertThat(dynamicType.locate(FOOBAR.replace('/', '.')).isResolved(), is(true));
+ assertThat(dynamicType.locate(QUXBAZ.replace('/', '.')).isResolved(), is(true));
+ assertThat(dynamicType.locate(BARBAZ.replace('/', '.')).isResolved(), is(false));
+ }
 }