https://www.graalvm.org/ 
class com.oracle.truffle.tck.tests.TestContext$1 implements java.util.function.Function<org.graalvm.polyglot.tck.LanguageProvider, java.util.Collection<? extends org.graalvm.polyglot.tck.Snippet>>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.oracle.truffle.tck.tests.TestContext$1
  super_class: java.lang.Object
{
  final com.oracle.truffle.tck.tests.TestContext this$0;
    descriptor: Lcom/oracle/truffle/tck/tests/TestContext;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  void <init>(com.oracle.truffle.tck.tests.TestContext);
    descriptor: (Lcom/oracle/truffle/tck/tests/TestContext;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.oracle.truffle.tck.tests.TestContext$1 this
         0: .line 183
            aload 0 /* this */
            aload 1
            putfield com.oracle.truffle.tck.tests.TestContext$1.this$0:Lcom/oracle/truffle/tck/tests/TestContext;
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // com.oracle.truffle.tck.tests.TestContext$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/tck/tests/TestContext$1;
    MethodParameters:
        Name  Flags
      this$0  final

  public java.util.Collection<? extends org.graalvm.polyglot.tck.Snippet> apply(org.graalvm.polyglot.tck.LanguageProvider);
    descriptor: (Lorg/graalvm/polyglot/tck/LanguageProvider;)Ljava/util/Collection;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=5, args_size=2
        start local 0 // com.oracle.truffle.tck.tests.TestContext$1 this
        start local 1 // org.graalvm.polyglot.tck.LanguageProvider tli
         0: .line 186
            aload 1 /* tli */
            aload 0 /* this */
            getfield com.oracle.truffle.tck.tests.TestContext$1.this$0:Lcom/oracle/truffle/tck/tests/TestContext;
            getfield com.oracle.truffle.tck.tests.TestContext.context:Lorg/graalvm/polyglot/Context;
            invokeinterface org.graalvm.polyglot.tck.LanguageProvider.createValueConstructors:(Lorg/graalvm/polyglot/Context;)Ljava/util/Collection;
            astore 2 /* result */
        start local 2 // java.util.Collection result
         1: .line 187
            aload 2 /* result */
            invokeinterface java.util.Collection.iterator:()Ljava/util/Iterator;
            astore 4
            goto 7
      StackMap locals: com.oracle.truffle.tck.tests.TestContext$1 org.graalvm.polyglot.tck.LanguageProvider java.util.Collection top java.util.Iterator
      StackMap stack:
         2: aload 4
            invokeinterface java.util.Iterator.next:()Ljava/lang/Object;
            checkcast org.graalvm.polyglot.tck.Snippet
            astore 3 /* snippet */
        start local 3 // org.graalvm.polyglot.tck.Snippet snippet
         3: .line 188
            aload 3 /* snippet */
            invokevirtual org.graalvm.polyglot.tck.Snippet.getParameterTypes:()Ljava/util/List;
            invokeinterface java.util.List.isEmpty:()Z
            ifne 5
         4: .line 189
            new java.lang.StringBuilder
            dup
            ldc "Value constructors cannot have parameters, invalid Snippet: "
            invokespecial java.lang.StringBuilder.<init>:(Ljava/lang/String;)V
            aload 3 /* snippet */
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/Object;)Ljava/lang/StringBuilder;
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
            invokestatic org.junit.Assert.fail:(Ljava/lang/String;)V
         5: .line 191
      StackMap locals: com.oracle.truffle.tck.tests.TestContext$1 org.graalvm.polyglot.tck.LanguageProvider java.util.Collection org.graalvm.polyglot.tck.Snippet java.util.Iterator
      StackMap stack:
            aload 3 /* snippet */
            invokevirtual org.graalvm.polyglot.tck.Snippet.getReturnType:()Lorg/graalvm/polyglot/tck/TypeDescriptor;
            invokevirtual org.graalvm.polyglot.tck.TypeDescriptor.isUnion:()Z
            ifeq 7
         6: .line 192
            new java.lang.StringBuilder
            dup
            ldc "Value constructors cannot return union types (use intersection type), invalid Snippet: "
            invokespecial java.lang.StringBuilder.<init>:(Ljava/lang/String;)V
            aload 3 /* snippet */
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/Object;)Ljava/lang/StringBuilder;
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
            invokestatic org.junit.Assert.fail:(Ljava/lang/String;)V
        end local 3 // org.graalvm.polyglot.tck.Snippet snippet
         7: .line 187
      StackMap locals: com.oracle.truffle.tck.tests.TestContext$1 org.graalvm.polyglot.tck.LanguageProvider java.util.Collection top java.util.Iterator
      StackMap stack:
            aload 4
            invokeinterface java.util.Iterator.hasNext:()Z
            ifne 2
         8: .line 195
            aload 2 /* result */
            areturn
        end local 2 // java.util.Collection result
        end local 1 // org.graalvm.polyglot.tck.LanguageProvider tli
        end local 0 // com.oracle.truffle.tck.tests.TestContext$1 this
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    9     0     this  Lcom/oracle/truffle/tck/tests/TestContext$1;
            0    9     1      tli  Lorg/graalvm/polyglot/tck/LanguageProvider;
            1    9     2   result  Ljava/util/Collection<+Lorg/graalvm/polyglot/tck/Snippet;>;
            3    7     3  snippet  Lorg/graalvm/polyglot/tck/Snippet;
    Signature: (Lorg/graalvm/polyglot/tck/LanguageProvider;)Ljava/util/Collection<+Lorg/graalvm/polyglot/tck/Snippet;>;
    MethodParameters:
      Name  Flags
      tli   

  public java.lang.Object apply(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x1041) ACC_PUBLIC, ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=2, locals=2, args_size=2
         0: .line 1
            aload 0
            aload 1
            checkcast org.graalvm.polyglot.tck.LanguageProvider
            invokevirtual com.oracle.truffle.tck.tests.TestContext$1.apply:(Lorg/graalvm/polyglot/tck/LanguageProvider;)Ljava/util/Collection;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature
}
Signature: Ljava/lang/Object;Ljava/util/function/Function<Lorg/graalvm/polyglot/tck/LanguageProvider;Ljava/util/Collection<+Lorg/graalvm/polyglot/tck/Snippet;>;>;
SourceFile: "TestContext.java"
EnclosingMethod: com.oracle.truffle.tck.tests.TestContext.getValueConstructors:(Lorg/graalvm/polyglot/tck/TypeDescriptor;[Ljava/lang/String;)Ljava/util/Collection;
NestHost: com.oracle.truffle.tck.tests.TestContext
InnerClasses:
  com.oracle.truffle.tck.tests.TestContext$1