Merge branch 'restrict-preview-check-bypass'

asm-commons/src/main/java/org/objectweb/asm/commons/AnnotationRemapper.java

@@ -83,9 +83,7 @@ public class AnnotationRemapper extends AnnotationVisitor {
     if (annotationVisitor == null) {
       return null;
     } else {
-      return annotationVisitor == av
-          ? this
-          : new AnnotationRemapper(api, annotationVisitor, remapper);
+      return annotationVisitor == av ? this : createAnnotationRemapper(annotationVisitor);
     }
   }
 
@@ -95,9 +93,18 @@ public class AnnotationRemapper extends AnnotationVisitor {
     if (annotationVisitor == null) {
       return null;
     } else {
-      return annotationVisitor == av
-          ? this
-          : new AnnotationRemapper(api, annotationVisitor, remapper);
+      return annotationVisitor == av ? this : createAnnotationRemapper(annotationVisitor);
     }
   }
+
+  /**
+   * Constructs a new remapper for annotations. The default implementation of this method returns a
+   * new {@link AnnotationRemapper}.
+   *
+   * @param annotationVisitor the AnnotationVisitor the remapper must delegate to.
+   * @return the newly created remapper.
+   */
+  protected AnnotationVisitor createAnnotationRemapper(final AnnotationVisitor annotationVisitor) {
+    return new AnnotationRemapper(api, annotationVisitor, remapper);
+  }
 }

asm-commons/src/main/java/org/objectweb/asm/commons/FieldRemapper.java

@@ -72,9 +72,7 @@ public class FieldRemapper extends FieldVisitor {
   public AnnotationVisitor visitAnnotation(final String descriptor, final boolean visible) {
     AnnotationVisitor annotationVisitor =
         super.visitAnnotation(remapper.mapDesc(descriptor), visible);
-    return annotationVisitor == null
-        ? null
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+    return annotationVisitor == null ? null : createAnnotationRemapper(annotationVisitor);
   }
 
   @Override
@@ -82,8 +80,17 @@ public class FieldRemapper extends FieldVisitor {
       final int typeRef, final TypePath typePath, final String descriptor, final boolean visible) {
     AnnotationVisitor annotationVisitor =
         super.visitTypeAnnotation(typeRef, typePath, remapper.mapDesc(descriptor), visible);
-    return annotationVisitor == null
-        ? null
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+    return annotationVisitor == null ? null : createAnnotationRemapper(annotationVisitor);
+  }
+
+  /**
+   * Constructs a new remapper for annotations. The default implementation of this method returns a
+   * new {@link AnnotationRemapper}.
+   *
+   * @param annotationVisitor the AnnotationVisitor the remapper must delegate to.
+   * @return the newly created remapper.
+   */
+  protected AnnotationVisitor createAnnotationRemapper(final AnnotationVisitor annotationVisitor) {
+    return new AnnotationRemapper(api, annotationVisitor, remapper);
   }
 }

asm-commons/src/main/java/org/objectweb/asm/commons/MethodRemapper.java

@@ -76,7 +76,7 @@ public class MethodRemapper extends MethodVisitor {
     AnnotationVisitor annotationVisitor = super.visitAnnotationDefault();
     return annotationVisitor == null
         ? annotationVisitor
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+        : createAnnotationRemapper(annotationVisitor);
   }
 
   @Override
@@ -85,7 +85,7 @@ public class MethodRemapper extends MethodVisitor {
         super.visitAnnotation(remapper.mapDesc(descriptor), visible);
     return annotationVisitor == null
         ? annotationVisitor
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+        : createAnnotationRemapper(annotationVisitor);
   }
 
   @Override
@@ -95,7 +95,7 @@ public class MethodRemapper extends MethodVisitor {
         super.visitTypeAnnotation(typeRef, typePath, remapper.mapDesc(descriptor), visible);
     return annotationVisitor == null
         ? annotationVisitor
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+        : createAnnotationRemapper(annotationVisitor);
   }
 
   @Override
@@ -105,7 +105,7 @@ public class MethodRemapper extends MethodVisitor {
         super.visitParameterAnnotation(parameter, remapper.mapDesc(descriptor), visible);
     return annotationVisitor == null
         ? annotationVisitor
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+        : createAnnotationRemapper(annotationVisitor);
   }
 
   @Override
@@ -209,7 +209,7 @@ public class MethodRemapper extends MethodVisitor {
         super.visitInsnAnnotation(typeRef, typePath, remapper.mapDesc(descriptor), visible);
     return annotationVisitor == null
         ? annotationVisitor
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+        : createAnnotationRemapper(annotationVisitor);
   }
 
   @Override
@@ -225,7 +225,7 @@ public class MethodRemapper extends MethodVisitor {
         super.visitTryCatchAnnotation(typeRef, typePath, remapper.mapDesc(descriptor), visible);
     return annotationVisitor == null
         ? annotationVisitor
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+        : createAnnotationRemapper(annotationVisitor);
   }
 
   @Override
@@ -259,6 +259,17 @@ public class MethodRemapper extends MethodVisitor {
             typeRef, typePath, start, end, index, remapper.mapDesc(descriptor), visible);
     return annotationVisitor == null
         ? annotationVisitor
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+        : createAnnotationRemapper(annotationVisitor);
+  }
+
+  /**
+   * Constructs a new remapper for annotations. The default implementation of this method returns a
+   * new {@link AnnotationRemapper}.
+   *
+   * @param annotationVisitor the AnnotationVisitor the remapper must delegate to.
+   * @return the newly created remapper.
+   */
+  protected AnnotationVisitor createAnnotationRemapper(final AnnotationVisitor annotationVisitor) {
+    return new AnnotationRemapper(api, annotationVisitor, remapper);
   }
 }

asm-commons/src/main/java/org/objectweb/asm/commons/RecordComponentRemapper.java

@@ -53,8 +53,7 @@ public class RecordComponentRemapper extends RecordComponentVisitor {
    */
   public RecordComponentRemapper(
       final RecordComponentVisitor recordComponentVisitor, final Remapper remapper) {
-    // TODO: add 'latest api =' comment when no longer experimental.
-    this(Opcodes.ASM8_EXPERIMENTAL, recordComponentVisitor, remapper);
+    this(/* latest api = */ Opcodes.ASM7, recordComponentVisitor, remapper);
   }
 
   /**
@@ -76,9 +75,7 @@ public class RecordComponentRemapper extends RecordComponentVisitor {
       final String descriptor, final boolean visible) {
     AnnotationVisitor annotationVisitor =
         super.visitAnnotationExperimental(remapper.mapDesc(descriptor), visible);
-    return annotationVisitor == null
-        ? null
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+    return annotationVisitor == null ? null : createAnnotationRemapper(annotationVisitor);
   }
 
   @Override
@@ -87,8 +84,17 @@ public class RecordComponentRemapper extends RecordComponentVisitor {
     AnnotationVisitor annotationVisitor =
         super.visitTypeAnnotationExperimental(
             typeRef, typePath, remapper.mapDesc(descriptor), visible);
-    return annotationVisitor == null
-        ? null
-        : new AnnotationRemapper(api, annotationVisitor, remapper);
+    return annotationVisitor == null ? null : createAnnotationRemapper(annotationVisitor);
+  }
+
+  /**
+   * Constructs a new remapper for annotations. The default implementation of this method returns a
+   * new {@link AnnotationRemapper}.
+   *
+   * @param annotationVisitor the AnnotationVisitor the remapper must delegate to.
+   * @return the newly created remapper.
+   */
+  protected AnnotationVisitor createAnnotationRemapper(final AnnotationVisitor annotationVisitor) {
+    return new AnnotationRemapper(api, annotationVisitor, remapper);
   }
 }

asm-commons/src/test/java/org/objectweb/asm/commons/ClassRemapperTest.java

@@ -38,12 +38,17 @@ import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.function.Executable;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.MethodSource;
+import org.objectweb.asm.AnnotationVisitor;
 import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassVisitor;
 import org.objectweb.asm.ClassWriter;
 import org.objectweb.asm.ConstantDynamic;
+import org.objectweb.asm.FieldVisitor;
 import org.objectweb.asm.Handle;
 import org.objectweb.asm.MethodVisitor;
+import org.objectweb.asm.ModuleVisitor;
 import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.RecordComponentVisitor;
 import org.objectweb.asm.Type;
 import org.objectweb.asm.test.AsmTest;
 import org.objectweb.asm.test.ClassFile;
@@ -149,7 +154,7 @@ public class ClassRemapperTest extends AsmTest {
     ClassNode classNode = new ClassNode();
     ClassRemapper classRemapper =
         new ClassRemapper(
-            /* latest */ Opcodes.ASM8_EXPERIMENTAL,
+            Opcodes.ASM7,
             classNode,
             new Remapper() {
               @Override
@@ -194,7 +199,7 @@ public class ClassRemapperTest extends AsmTest {
     ClassWriter classWriter = new ClassWriter(0);
     UpperCaseRemapper upperCaseRemapper = new UpperCaseRemapper(classParameter.getInternalName());
     ClassRemapper classRemapper =
-        new ClassRemapper(apiParameter.value(), classWriter, upperCaseRemapper);
+        newClassRemapper(apiParameter.value(), classWriter, upperCaseRemapper);
 
     Executable accept = () -> classReader.accept(classRemapper, 0);
 
@@ -225,7 +230,7 @@ public class ClassRemapperTest extends AsmTest {
     ClassWriter classWriter = new ClassWriter(0);
     UpperCaseRemapper upperCaseRemapper = new UpperCaseRemapper(classParameter.getInternalName());
     ClassRemapper classRemapper =
-        new ClassRemapper(apiParameter.value(), classWriter, upperCaseRemapper);
+        newClassRemapper(apiParameter.value(), classWriter, upperCaseRemapper);
 
     Executable accept = () -> classNode.accept(classRemapper);
 
@@ -256,6 +261,81 @@ public class ClassRemapperTest extends AsmTest {
     checkMethodAdapter.visitFieldInsn(Opcodes.GETFIELD, internalName, "name", "I");
   }
 
+  ClassRemapper newClassRemapper(
+      final int api, final ClassVisitor classVisitor, final Remapper remapper) {
+    // TODO: remove this test and the associated classes when no longer experimental.
+    if (api == Opcodes.ASM8_EXPERIMENTAL) {
+      return new ClassRemapperExperimental(classVisitor, remapper);
+    }
+    return new ClassRemapper(api, classVisitor, remapper);
+  }
+
+  static class ClassRemapperExperimental extends ClassRemapper {
+
+    ClassRemapperExperimental(final ClassVisitor classVisitor, final Remapper remapper) {
+      super(Opcodes.ASM8_EXPERIMENTAL, classVisitor, remapper);
+    }
+
+    @Override
+    protected RecordComponentVisitor createRecordComponentRemapper(
+        final RecordComponentVisitor recordComponentVisitor) {
+      return new RecordComponentRemapper(api, recordComponentVisitor, remapper) {
+        @Override
+        protected AnnotationVisitor createAnnotationRemapper(
+            final AnnotationVisitor annotationVisitor) {
+          return new AnnotationRemapperExperimental(annotationVisitor, remapper);
+        }
+      };
+    }
+
+    @Override
+    protected FieldVisitor createFieldRemapper(final FieldVisitor fieldVisitor) {
+      return new FieldRemapper(api, fieldVisitor, remapper) {
+        @Override
+        protected AnnotationVisitor createAnnotationRemapper(
+            final AnnotationVisitor annotationVisitor) {
+          return new AnnotationRemapperExperimental(annotationVisitor, remapper);
+        }
+      };
+    }
+
+    @Override
+    protected MethodVisitor createMethodRemapper(final MethodVisitor methodVisitor) {
+      return new MethodRemapper(api, methodVisitor, remapper) {
+        @Override
+        protected AnnotationVisitor createAnnotationRemapper(
+            final AnnotationVisitor annotationVisitor) {
+          return new AnnotationRemapperExperimental(annotationVisitor, remapper);
+        }
+      };
+    }
+
+    @Override
+    protected AnnotationVisitor createAnnotationRemapper(
+        final AnnotationVisitor annotationVisitor) {
+      return new AnnotationRemapperExperimental(annotationVisitor, remapper);
+    }
+
+    @Override
+    protected ModuleVisitor createModuleRemapper(final ModuleVisitor moduleVisitor) {
+      return new ModuleRemapper(api, moduleVisitor, remapper) {};
+    }
+  }
+
+  static class AnnotationRemapperExperimental extends AnnotationRemapper {
+
+    AnnotationRemapperExperimental(
+        final AnnotationVisitor annotationVisitor, final Remapper remapper) {
+      super(Opcodes.ASM8_EXPERIMENTAL, annotationVisitor, remapper);
+    }
+
+    @Override
+    protected AnnotationVisitor createAnnotationRemapper(
+        final AnnotationVisitor annotationVisitor) {
+      return new AnnotationRemapperExperimental(annotationVisitor, remapper);
+    }
+  }
+
   static class UpperCaseRemapper extends Remapper {
 
     private static final Locale LOCALE = Locale.ENGLISH;

asm-commons/src/test/java/org/objectweb/asm/commons/GeneratorAdapterTest.java

@@ -852,7 +852,7 @@ public class GeneratorAdapterTest {
               new TraceMethodVisitor(textifier),
               access,
               name,
-              descriptor);
+              descriptor) {};
     }
 
     public String push(final boolean value) {

asm-commons/src/test/java/org/objectweb/asm/commons/JsrInlinerAdapterTest.java

@@ -1534,7 +1534,7 @@ public class JsrInlinerAdapterTest extends AsmTest {
       MethodVisitor methodVisitor =
           super.visitMethod(access, name, descriptor, signature, exceptions);
       return new JSRInlinerAdapter(
-          api, methodVisitor, access, name, descriptor, signature, exceptions);
+          api, methodVisitor, access, name, descriptor, signature, exceptions) {};
     }
   }
 }

asm-commons/src/test/java/org/objectweb/asm/commons/LocalVariablesSorterTest.java

@@ -240,7 +240,7 @@ public class LocalVariablesSorterTest extends AsmTest {
         final String[] exceptions) {
       MethodVisitor methodVisitor =
           super.visitMethod(access, name, descriptor, signature, exceptions);
-      return new LocalVariablesSorter(api, access, descriptor, methodVisitor);
+      return new LocalVariablesSorter(api, access, descriptor, methodVisitor) {};
     }
   }
 }

asm-commons/src/test/java/org/objectweb/asm/commons/SerialVersionUidAdderTest.java

@@ -123,7 +123,7 @@ public class SerialVersionUidAdderTest extends AsmTest {
     ClassWriter classWriter = new ClassWriter(0);
 
     classReader.accept(
-        new SerialVersionUIDAdder(/* latest */ Opcodes.ASM8_EXPERIMENTAL, classWriter), 0);
+        new SerialVersionUIDAdder(/* latest */ Opcodes.ASM8_EXPERIMENTAL, classWriter) {}, 0);
 
     if ((classReader.getAccess() & Opcodes.ACC_ENUM) == 0) {
       assertTrue(new ClassFile(classWriter.toByteArray()).toString().contains("serialVersionUID"));

asm-tree/src/test/java/org/objectweb/asm/tree/ClassNodeTest.java

@@ -83,7 +83,7 @@ public class ClassNodeTest extends AsmTest {
   @ParameterizedTest
   @MethodSource(ALL_CLASSES_AND_ALL_APIS)
   public void testCheck(final PrecompiledClass classParameter, final Api apiParameter) {
-    ClassNode classNode = new ClassNode(apiParameter.value());
+    ClassNode classNode = new ClassNode(apiParameter.value()) {};
     new ClassReader(classParameter.getBytes()).accept(classNode, attributes(), 0);
 
     Executable check = () -> classNode.check(apiParameter.value());
@@ -101,7 +101,7 @@ public class ClassNodeTest extends AsmTest {
   public void testVisitAndAccept(final PrecompiledClass classParameter, final Api apiParameter) {
     byte[] classFile = classParameter.getBytes();
     ClassReader classReader = new ClassReader(classFile);
-    ClassNode classNode = new ClassNode(apiParameter.value());
+    ClassNode classNode = new ClassNode(apiParameter.value()) {};
     ClassWriter classWriter = new ClassWriter(0);
 
     classReader.accept(classNode, attributes(), 0);
@@ -120,7 +120,7 @@ public class ClassNodeTest extends AsmTest {
       final PrecompiledClass classParameter, final Api apiParameter) {
     byte[] classFile = classParameter.getBytes();
     ClassReader classReader = new ClassReader(classFile);
-    ClassNode classNode = new ClassNode(apiParameter.value());
+    ClassNode classNode = new ClassNode(apiParameter.value()) {};
     ClassWriter classWriter = new ClassWriter(0);
 
     classReader.accept(classNode, attributes(), 0);
@@ -139,7 +139,7 @@ public class ClassNodeTest extends AsmTest {
       final PrecompiledClass classParameter, final Api apiParameter) {
     byte[] classFile = classParameter.getBytes();
     ClassReader classReader = new ClassReader(classFile);
-    ClassNode classNode = new ClassNode(apiParameter.value());
+    ClassNode classNode = new ClassNode(apiParameter.value()) {};
     ClassWriter classWriter = new ClassWriter(0);
 
     classReader.accept(classNode, attributes(), 0);

asm-tree/src/test/java/org/objectweb/asm/tree/ModuleNodeTest.java

@@ -57,7 +57,7 @@ public class ModuleNodeTest extends AsmTest {
             null,
             null,
             null,
-            null);
+            null) {};
 
     assertEquals("module1", moduleNode1.name);
     assertEquals(123, moduleNode1.access);

asm-util/src/test/java/org/objectweb/asm/util/SignaturesProviders.java

@@ -26,7 +26,9 @@ public final class SignaturesProviders {
 
   static {
     AsmTest.allClassesAndLatestApi()
-        .forEach(argument -> collectSignatures((PrecompiledClass) argument.get()[0]));
+        .map(argument -> (PrecompiledClass) argument.get()[0])
+        .filter(precompiledClass -> !precompiledClass.isMoreRecentThan(AsmTest.Api.ASM7))
+        .forEach(precompiledClass -> collectSignatures(precompiledClass));
     assertFalse(CLASS_SIGNATURES.isEmpty());
     assertFalse(FIELD_SIGNATURES.isEmpty());
     assertFalse(METHOD_SIGNATURES.isEmpty());
@@ -37,7 +39,7 @@ public final class SignaturesProviders {
   private static void collectSignatures(final PrecompiledClass classParameter) {
     ClassReader classReader = new ClassReader(classParameter.getBytes());
     classReader.accept(
-        new ClassVisitor(/* latest */ Opcodes.ASM8_EXPERIMENTAL) {
+        new ClassVisitor(Opcodes.ASM7) {
           @Override
           public void visit(
               final int version,

asm/src/main/java/org/objectweb/asm/Constants.java

@@ -30,6 +30,7 @@ package org.objectweb.asm;
 import java.io.DataInputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.regex.Pattern;
 
 /**
  * Defines additional JVM opcodes, access flags and constants which are not part of the ASM public
@@ -183,20 +184,34 @@ final class Constants implements Opcodes {
 
   static void checkAsm8Experimental(final Object caller) {
     Class<?> callerClass = caller.getClass();
-    if (callerClass.getName().startsWith("org.objectweb.asm.")) {
-      return;
+    String internalName = callerClass.getName().replace('.', '/');
+    if (!isWhitelisted(internalName)) {
+      checkIsPreview(callerClass.getClassLoader().getResourceAsStream(internalName + ".class"));
     }
-    String callerClassResource = callerClass.getName().replace('.', '/') + ".class";
-    InputStream inputStream = callerClass.getClassLoader().getResourceAsStream(callerClassResource);
-    if (inputStream == null) {
+  }
+
+  static boolean isWhitelisted(final String internalName) {
+    if (!internalName.startsWith("org/objectweb/asm/")) {
+      return false;
+    }
+    String member = "(Annotation|Class|Field|Method|Module|RecordComponent|Signature)";
+    return internalName.contains("Test$")
+        || Pattern.matches(
+            "org/objectweb/asm/util/Trace" + member + "Visitor(\\$.*)?", internalName)
+        || Pattern.matches(
+            "org/objectweb/asm/util/Check" + member + "Adapter(\\$.*)?", internalName);
+  }
+
+  static void checkIsPreview(final InputStream classInputStream) {
+    if (classInputStream == null) {
       throw new IllegalStateException("Bytecode not available, can't check class version");
     }
     int minorVersion;
-    try (DataInputStream callerClassStream = new DataInputStream(inputStream); ) {
+    try (DataInputStream callerClassStream = new DataInputStream(classInputStream); ) {
       callerClassStream.readInt();
       minorVersion = callerClassStream.readUnsignedShort();
     } catch (IOException ioe) {
-      throw new IllegalStateException("i/O error, can't check class version", ioe);
+      throw new IllegalStateException("I/O error, can't check class version", ioe);
     }
     if (minorVersion != 0xFFFF) {
       throw new IllegalStateException(

asm/src/main/java/org/objectweb/asm/RecordComponentWriter.java

@@ -103,8 +103,7 @@ final class RecordComponentWriter extends RecordComponentVisitor {
       final String name,
       final String descriptor,
       final String signature) {
-    // TODO: add 'latest api =' comment when no longer experimental.
-    super(Opcodes.ASM8_EXPERIMENTAL);
+    super(/* latest api = */ Opcodes.ASM7);
     this.symbolTable = symbolTable;
     this.accessFlags = accessFlags;
     this.nameIndex = symbolTable.addConstantUtf8(name);

asm/src/test/java/org/objectweb/asm/ConstantsTest.java

@@ -27,14 +27,21 @@
 // THE POSSIBILITY OF SUCH DAMAGE.
 package org.objectweb.asm;
 
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
 import java.lang.reflect.Field;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Set;
 import java.util.stream.Collectors;
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.function.Executable;
 
 /**
  * Unit tests for {@link Constants}.
@@ -161,6 +168,52 @@ public class ConstantsTest {
     }
   }
 
+  @Test
+  public void testIsWhitelisted() {
+    assertFalse(Constants.isWhitelisted("org/jacoco/core/internal/flow/ClassProbesVisitor"));
+    assertFalse(Constants.isWhitelisted("org/objectweb/asm/ClassWriter"));
+    assertFalse(Constants.isWhitelisted("org/objectweb/asm/util/CheckClassVisitor"));
+    assertFalse(Constants.isWhitelisted("org/objectweb/asm/ClassWriterTest"));
+    assertTrue(Constants.isWhitelisted("org/objectweb/asm/ClassWriterTest$DeadCodeInserter"));
+    assertTrue(Constants.isWhitelisted("org/objectweb/asm/util/TraceClassVisitor"));
+    assertTrue(Constants.isWhitelisted("org/objectweb/asm/util/CheckClassAdapter"));
+  }
+
+  @Test
+  public void testCheckIsPreview_nullStream() {
+    Executable checkIsPreview = () -> Constants.checkIsPreview(null);
+
+    assertThrows(IllegalStateException.class, checkIsPreview);
+  }
+
+  @Test
+  public void testCheckIsPreview_invalidStream() {
+    InputStream invalidStream = new ByteArrayInputStream(new byte[4]);
+
+    Executable checkIsPreview = () -> Constants.checkIsPreview(invalidStream);
+
+    assertThrows(IllegalStateException.class, checkIsPreview);
+  }
+
+  @Test
+  public void testCheckIsPreview_nonPreviewClass() {
+    InputStream nonPreviewStream = new ByteArrayInputStream(new byte[8]);
+
+    Executable checkIsPreview = () -> Constants.checkIsPreview(nonPreviewStream);
+
+    assertThrows(IllegalStateException.class, checkIsPreview);
+  }
+
+  @Test
+  public void testCheckIsPreview_previewClass() {
+    byte[] previewClass = new byte[] {0, 0, 0, 0, (byte) 0xFF, (byte) 0xFF};
+    InputStream previewStream = new ByteArrayInputStream(previewClass);
+
+    Executable checkIsPreview = () -> Constants.checkIsPreview(previewStream);
+
+    assertDoesNotThrow(checkIsPreview);
+  }
+
   private static List<Field> getConstants(final ConstantType constantType) {
     return Arrays.asList(Constants.class.getFields()).stream()
         .filter(field -> getType(field).equals(constantType))

asm/src/test/java/org/objectweb/asm/signature/SignaturesProviders.java

@@ -26,7 +26,9 @@ public final class SignaturesProviders {
 
   static {
     AsmTest.allClassesAndLatestApi()
-        .forEach(argument -> collectSignatures((PrecompiledClass) argument.get()[0]));
+        .map(argument -> (PrecompiledClass) argument.get()[0])
+        .filter(precompiledClass -> !precompiledClass.isMoreRecentThan(AsmTest.Api.ASM7))
+        .forEach(precompiledClass -> collectSignatures(precompiledClass));
     assertFalse(CLASS_SIGNATURES.isEmpty());
     assertFalse(FIELD_SIGNATURES.isEmpty());
     assertFalse(METHOD_SIGNATURES.isEmpty());
@@ -37,7 +39,7 @@ public final class SignaturesProviders {
   private static void collectSignatures(final PrecompiledClass classParameter) {
     ClassReader classReader = new ClassReader(classParameter.getBytes());
     classReader.accept(
-        new ClassVisitor(/* latest */ Opcodes.ASM8_EXPERIMENTAL) {
+        new ClassVisitor(Opcodes.ASM7) {
           @Override
           public void visit(
               final int version,