https://jsoup.org/: jsoup is a Java library for working with real-world HTML. It provides a very convenient API for extracting and manipulating data, using the best of DOM, CSS, and jquery-like methods. jsoup implements the WHATWG HTML5 specification, and parses HTML to the same DOM as modern browsers do. (Jonathan Hedley)
  • Jonathan Hedley 
class org.jsoup.nodes.Attributes$Dataset extends java.util.AbstractMap<java.lang.String, java.lang.String>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: org.jsoup.nodes.Attributes$Dataset
  super_class: java.util.AbstractMap
{
  private final org.jsoup.nodes.Attributes attributes;
    descriptor: Lorg/jsoup/nodes/Attributes;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private void <init>(org.jsoup.nodes.Attributes);
    descriptor: (Lorg/jsoup/nodes/Attributes;)V
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // org.jsoup.nodes.Attributes$Dataset this
        start local 1 // org.jsoup.nodes.Attributes attributes
         0: .line 388
            aload 0 /* this */
            invokespecial java.util.AbstractMap.<init>:()V
         1: .line 389
            aload 0 /* this */
            aload 1 /* attributes */
            putfield org.jsoup.nodes.Attributes$Dataset.attributes:Lorg/jsoup/nodes/Attributes;
         2: .line 390
            return
        end local 1 // org.jsoup.nodes.Attributes attributes
        end local 0 // org.jsoup.nodes.Attributes$Dataset this
      LocalVariableTable:
        Start  End  Slot        Name  Signature
            0    3     0        this  Lorg/jsoup/nodes/Attributes$Dataset;
            0    3     1  attributes  Lorg/jsoup/nodes/Attributes;
    MethodParameters:
            Name  Flags
      attributes  

  public java.util.Set<java.util.Map$Entry<java.lang.String, java.lang.String>> entrySet();
    descriptor: ()Ljava/util/Set;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=1, args_size=1
        start local 0 // org.jsoup.nodes.Attributes$Dataset this
         0: .line 394
            new org.jsoup.nodes.Attributes$Dataset$EntrySet
            dup
            aload 0 /* this */
            invokespecial org.jsoup.nodes.Attributes$Dataset$EntrySet.<init>:(Lorg/jsoup/nodes/Attributes$Dataset;)V
            areturn
        end local 0 // org.jsoup.nodes.Attributes$Dataset this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/jsoup/nodes/Attributes$Dataset;
    Signature: ()Ljava/util/Set<Ljava/util/Map$Entry<Ljava/lang/String;Ljava/lang/String;>;>;

  public java.lang.String put(java.lang.String, java.lang.String);
    descriptor: (Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=5, args_size=3
        start local 0 // org.jsoup.nodes.Attributes$Dataset this
        start local 1 // java.lang.String key
        start local 2 // java.lang.String value
         0: .line 399
            aload 1 /* key */
            invokestatic org.jsoup.nodes.Attributes.dataKey:(Ljava/lang/String;)Ljava/lang/String;
            astore 3 /* dataKey */
        start local 3 // java.lang.String dataKey
         1: .line 400
            aload 0 /* this */
            getfield org.jsoup.nodes.Attributes$Dataset.attributes:Lorg/jsoup/nodes/Attributes;
            aload 3 /* dataKey */
            invokevirtual org.jsoup.nodes.Attributes.hasKey:(Ljava/lang/String;)Z
            ifeq 2
            aload 0 /* this */
            getfield org.jsoup.nodes.Attributes$Dataset.attributes:Lorg/jsoup/nodes/Attributes;
            aload 3 /* dataKey */
            invokevirtual org.jsoup.nodes.Attributes.get:(Ljava/lang/String;)Ljava/lang/String;
            goto 3
      StackMap locals: java.lang.String
      StackMap stack:
         2: aconst_null
      StackMap locals:
      StackMap stack: java.lang.String
         3: astore 4 /* oldValue */
        start local 4 // java.lang.String oldValue
         4: .line 401
            aload 0 /* this */
            getfield org.jsoup.nodes.Attributes$Dataset.attributes:Lorg/jsoup/nodes/Attributes;
            aload 3 /* dataKey */
            aload 2 /* value */
            invokevirtual org.jsoup.nodes.Attributes.put:(Ljava/lang/String;Ljava/lang/String;)Lorg/jsoup/nodes/Attributes;
            pop
         5: .line 402
            aload 4 /* oldValue */
            areturn
        end local 4 // java.lang.String oldValue
        end local 3 // java.lang.String dataKey
        end local 2 // java.lang.String value
        end local 1 // java.lang.String key
        end local 0 // org.jsoup.nodes.Attributes$Dataset this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0    6     0      this  Lorg/jsoup/nodes/Attributes$Dataset;
            0    6     1       key  Ljava/lang/String;
            0    6     2     value  Ljava/lang/String;
            1    6     3   dataKey  Ljava/lang/String;
            4    6     4  oldValue  Ljava/lang/String;
    MethodParameters:
       Name  Flags
      key    
      value  

  public java.lang.Object put(java.lang.Object, java.lang.Object);
    descriptor: (Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x1041) ACC_PUBLIC, ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=3, locals=3, args_size=3
         0: .line 1
            aload 0
            aload 1
            checkcast java.lang.String
            aload 2
            checkcast java.lang.String
            invokevirtual org.jsoup.nodes.Attributes$Dataset.put:(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature
}
Signature: Ljava/util/AbstractMap<Ljava/lang/String;Ljava/lang/String;>;
SourceFile: "Attributes.java"
NestHost: org.jsoup.nodes.Attributes
InnerClasses:
  public abstract Entry = java.util.Map$Entry of java.util.Map
  private Dataset = org.jsoup.nodes.Attributes$Dataset of org.jsoup.nodes.Attributes
  private DatasetIterator = org.jsoup.nodes.Attributes$Dataset$DatasetIterator of org.jsoup.nodes.Attributes$Dataset
  private EntrySet = org.jsoup.nodes.Attributes$Dataset$EntrySet of org.jsoup.nodes.Attributes$Dataset