https://www.graalvm.org/ 
class org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues implements java.util.function.Function<java.lang.String, java.lang.String>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues
  super_class: java.lang.Object
{
  private final java.util.jar.Manifest mf;
    descriptor: Ljava/util/jar/Manifest;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final java.util.jar.Attributes mainAttributes;
    descriptor: Ljava/util/jar/Attributes;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  void <init>(java.util.jar.JarFile);
    descriptor: (Ljava/util/jar/JarFile;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues this
        start local 1 // java.util.jar.JarFile jf
         0: .line 76
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 77
            aload 0 /* this */
            aload 1 /* jf */
            invokevirtual java.util.jar.JarFile.getManifest:()Ljava/util/jar/Manifest;
            putfield org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues.mf:Ljava/util/jar/Manifest;
         2: .line 78
            aload 0 /* this */
            aload 0 /* this */
            getfield org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues.mf:Ljava/util/jar/Manifest;
            ifnonnull 3
            aconst_null
            goto 4
      StackMap locals: org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues java.util.jar.JarFile
      StackMap stack: org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues
         3: aload 0 /* this */
            getfield org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues.mf:Ljava/util/jar/Manifest;
            invokevirtual java.util.jar.Manifest.getMainAttributes:()Ljava/util/jar/Attributes;
      StackMap locals: org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues java.util.jar.JarFile
      StackMap stack: org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues java.util.jar.Attributes
         4: putfield org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues.mainAttributes:Ljava/util/jar/Attributes;
         5: .line 79
            return
        end local 1 // java.util.jar.JarFile jf
        end local 0 // org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    6     0  this  Lorg/graalvm/component/installer/jar/JarMetaLoader$ManifestValues;
            0    6     1    jf  Ljava/util/jar/JarFile;
    Exceptions:
      throws java.io.IOException
    MethodParameters:
      Name  Flags
      jf    

  public java.lang.String apply(java.lang.String);
    descriptor: (Ljava/lang/String;)Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues this
        start local 1 // java.lang.String t
         0: .line 83
            aload 0 /* this */
            getfield org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues.mainAttributes:Ljava/util/jar/Attributes;
            ifnonnull 1
            aconst_null
            goto 2
      StackMap locals:
      StackMap stack:
         1: aload 0 /* this */
            getfield org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues.mainAttributes:Ljava/util/jar/Attributes;
            aload 1 /* t */
            invokevirtual java.util.jar.Attributes.getValue:(Ljava/lang/String;)Ljava/lang/String;
      StackMap locals:
      StackMap stack: java.lang.String
         2: areturn
        end local 1 // java.lang.String t
        end local 0 // org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Lorg/graalvm/component/installer/jar/JarMetaLoader$ManifestValues;
            0    3     1     t  Ljava/lang/String;
    MethodParameters:
      Name  Flags
      t     

  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 java.lang.String
            invokevirtual org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues.apply:(Ljava/lang/String;)Ljava/lang/String;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature
}
Signature: Ljava/lang/Object;Ljava/util/function/Function<Ljava/lang/String;Ljava/lang/String;>;
SourceFile: "JarMetaLoader.java"
NestHost: org.graalvm.component.installer.jar.JarMetaLoader
InnerClasses:
  private ManifestValues = org.graalvm.component.installer.jar.JarMetaLoader$ManifestValues of org.graalvm.component.installer.jar.JarMetaLoader