Fix use of ASM class reader and writer.

Author: raphw

byte-buddy-dep/src/main/java/net/bytebuddy/utility/AsmClassReader.java

@@ -32,6 +32,11 @@
  */
 public interface AsmClassReader {
 
+    /**
+     * Indicates that no custom attributes should be mapped.
+     */
+    Attribute[] NO_ATTRIBUTES = new Attribute[0];
+
     /**
      * Unwraps a class reader to the underlying reader mechanism.
      *
@@ -138,7 +143,9 @@ public AsmClassReader make(byte[] binaryRepresentation, boolean experimental) {
                  * {@inheritDoc}
                  */
                 public AsmClassReader make(byte[] binaryRepresentation, boolean experimental) {
-                    return new AsmClassReader.ForClassFileApi(ForClassFileApi.DISPATCHER.make(binaryRepresentation));
+                    return new AsmClassReader.ForClassFileApi(ForClassFileApi.DISPATCHER.make(
+                            binaryRepresentation,
+                            NO_ATTRIBUTES));
                 }
             };
 
@@ -187,11 +194,6 @@ public AsmClassReader make(byte[] binaryRepresentation) {
      */
     class ForAsm implements AsmClassReader {
 
-        /**
-         * Indicates that no custom attributes should be mapped.
-         */
-        private static final Attribute[] NO_ATTRIBUTES = new Attribute[0];
-
         /**
          * The class reader that represents the class file to be read.
          */
@@ -271,7 +273,9 @@ private static <T> T doPrivileged(PrivilegedAction<T> action) {
          */
         @MaybeNull
         public <T> T unwrap(Class<T> type) {
-            return null;
+            return type.isInstance(classReader)
+                    ? type.cast(classReader)
+                    : null;
         }
 
         /**
@@ -293,17 +297,18 @@ protected interface JdkClassReader {
              * @param value The instance to evaluate.
              * @return {@code true} if the supplied object is an instance of {@code codes.rafael.asmjdkbridge.JdkClassReader}.
              */
-            @JavaDispatcher.IsConstructor
+            @JavaDispatcher.Instance
             boolean isInstance(Object value);
 
             /**
              * Creates an instance of {@code codes.rafael.asmjdkbridge.JdkClassReader}.
              *
              * @param binaryRepresentation The binary representation of a class file to represent through the reader.
+             * @param attribute            An array of attribute prototypes.
              * @return A new instance of {@code codes.rafael.asmjdkbridge.JdkClassReader}.
              */
             @JavaDispatcher.IsConstructor
-            Object make(byte[] binaryRepresentation);
+            Object make(byte[] binaryRepresentation, Attribute[] attribute);
 
             /**
              * Accepts a class reader to visit the represented class file.

byte-buddy-dep/src/main/java/net/bytebuddy/utility/AsmClassWriter.java

@@ -168,8 +168,8 @@ public AsmClassWriter make(int flags, AsmClassReader classReader, TypePool typeP
                                 SuperClassResolvingJdkClassWriter.GET_SUPER_CLASS,
                                 new SuperClassResolvingJdkClassWriter(typePool)));
                     } else {
-                        return new ForClassFileApi(ForClassFileApi.DISPATCHER.make(flags,
-                                jdkClassReader,
+                        return new ForClassFileApi(ForClassFileApi.DISPATCHER.make(jdkClassReader,
+                                flags,
                                 SuperClassResolvingJdkClassWriter.GET_SUPER_CLASS,
                                 new SuperClassResolvingJdkClassWriter(typePool)));
                     }
@@ -439,15 +439,15 @@ protected interface JdkClassWriter {
             /**
              * Create a new {@code codes.rafael.asmjdkbridge.JdkClassWriter}.
              *
-             * @param flags         The flags to consider.
              * @param classReader   The class reader of which to reuse the constant pool.
+             * @param flags         The flags to consider.
              * @param getSuperClass A resolver for the super class.
              * @param target        The target to invoke the super class resolver upon.
              * @return A new {@code codes.rafael.asmjdkbridge.JdkClassWriter}.
              */
             @JavaDispatcher.IsConstructor
-            ClassVisitor make(int flags,
-                              @JavaDispatcher.Proxied("codes.rafael.asmjdkbridge.JdkClassReader") Object classReader,
+            ClassVisitor make(@JavaDispatcher.Proxied("codes.rafael.asmjdkbridge.JdkClassReader") Object classReader,
+                              int flags,
                               Method getSuperClass,
                               Object target);
 

byte-buddy-dep/src/test/java/net/bytebuddy/ByteBuddyTest.java

@@ -9,6 +9,8 @@
 import net.bytebuddy.implementation.StubMethod;
 import net.bytebuddy.matcher.ElementMatchers;
 import net.bytebuddy.test.utility.JavaVersionRule;
+import net.bytebuddy.utility.AsmClassReader;
+import net.bytebuddy.utility.AsmClassWriter;
 import org.junit.Rule;
 import org.junit.Test;
 
@@ -199,6 +201,49 @@ public void testCallerSuffixNamingStrategy() throws Exception {
                 + "$testCallerSuffixNamingStrategy$SuffixedName"));
     }
 
+    @Test
+    @JavaVersionRule.Enforce(24)
+    public void testCanUseClassFileApiReaderAndWriter() throws Exception {
+        Class<?> type = new ByteBuddy()
+                .with(AsmClassReader.Factory.Default.CLASS_FILE_API_ONLY)
+                .with(AsmClassWriter.Factory.Default.CLASS_FILE_API_ONLY)
+                .redefine(Recorder.class)
+                .make()
+                .load(ClassLoadingStrategy.BOOTSTRAP_LOADER, ClassLoadingStrategy.Default.WRAPPER)
+                .getLoaded();
+        Object object = type.getConstructor().newInstance();
+        type.getMethod("instrument").invoke(object);
+        assertThat(type.getField("counter").get(object), is((Object) 1));
+    }
+
+    @Test
+    @JavaVersionRule.Enforce(24)
+    public void testCanUseClassFileApiReaderOnly() throws Exception {
+        Class<?> type = new ByteBuddy()
+                .with(AsmClassReader.Factory.Default.CLASS_FILE_API_ONLY)
+                .redefine(Recorder.class)
+                .make()
+                .load(ClassLoadingStrategy.BOOTSTRAP_LOADER, ClassLoadingStrategy.Default.WRAPPER)
+                .getLoaded();
+        Object object = type.getConstructor().newInstance();
+        type.getMethod("instrument").invoke(object);
+        assertThat(type.getField("counter").get(object), is((Object) 1));
+    }
+
+    @Test
+    @JavaVersionRule.Enforce(24)
+    public void testCanUseClassFileApiWriterOnly() throws Exception {
+        Class<?> type = new ByteBuddy()
+                .with(AsmClassWriter.Factory.Default.CLASS_FILE_API_ONLY)
+                .redefine(Recorder.class)
+                .make()
+                .load(ClassLoadingStrategy.BOOTSTRAP_LOADER, ClassLoadingStrategy.Default.WRAPPER)
+                .getLoaded();
+        Object object = type.getConstructor().newInstance();
+        type.getMethod("instrument").invoke(object);
+        assertThat(type.getField("counter").get(object), is((Object) 1));
+    }
+
     public static class Recorder {
 
         public int counter;