LJV

LJV ljv = new LJV()
    .setQualifyNestedClassNames(true)
    .setIgnoreNullValuedFields(true)
    .addFieldAttribute("sourceSpliterator", "constraint=false");

Stream<Integer> o =
    List.of(1, 2, 3)
    .stream()
    .map(x -> x * x)
    .filter(x -> x % 2 == 0);

//DOT script
String dot = ljv.drawGraph(o);

//use GraphViz online
String encoded = URLEncoder.encode(dot, "UTF8")
                .replaceAll("\\+", "%20");
Desktop.getDesktop().browse(
    new URI("https://dreampuf.github.io/GraphvizOnline/#"
                        + encoded));

 new LJV().drawGraph("Hello");

"The quick brown fox jumps over the lazy dog".split(" ")

"The quick brown fox jumps over the lazy dog".substring(0, 3)

"The quick brown fox jumps over the lazy dog".split(" ")

"The quick brown fox jumps over the lazy dog".substring(0, 3)

new String[]{"Hello!", "Привет!"}

new String[]{"Hello!", "Привет!"}

String[] s = new String[]{"f5a5a608", "abc"};
System.out.println(s[0].hashCode()); //0
System.out.println(s[1].hashCode()); //96354

String[] s = new String[]{"f5a5a608", "abc"};
System.out.println(s[0].hashCode()); //0
System.out.println(s[1].hashCode()); //96354

LJV ljv = new LJV().addIgnoreField("hash")
    .addIgnoreField("coder").addIgnoreField("hashIsZero");
String x = "Hello";
new String[]{x,
             new String(x),
             new String(x.toCharArray()),
             x + "",
             "" + x,
             x.concat(""),
             "".concat(x)}

    /*0*/   x,
    /*1*/   new String(x),  //переиспользуется буфер
    /*2*/   new String(x.toCharArray()),
    /*3*/   x + "",
    /*4*/   "" + x,
    /*5*/   x.concat(""),   //переиспользуется весь x
    /*6*/   "".concat(x)

    /*0*/   x,
    /*1*/   new String(x),
    /*2*/   new String(x.toCharArray()),
    /*3*/   x + "",
    /*4*/   "" + x,
    /*5*/   x.concat(""),   //переиспользуется весь x
    /*6*/   "".concat(x)

new Integer[]{
    42,
    42,
    Integer.valueOf(42),
    new Integer(42),
    -4242,
    -4242
}

/*0*/ 42,
/*1*/ 42, // дедуплицируется диапазон -128 .. 127
          // или -128 .. -XX:AutoBoxCacheMax
/*2*/ Integer.valueOf(42), //дедуплицируется
/*3*/ new Integer(42),   //НЕ дедуплицируется, deprecated since Java9
/*4*/ -4242,
/*5*/ -4242              //не дедуплицируется (вне диапазона)

LJV ljv = new LJV().setDirection(Direction.LR)
    .addFieldAttribute("last", "constraint=false")
    .addFieldAttribute("prev", "constraint=false")
    .setTreatAsPrimitive(Integer.class);

List<Integer> list = new LinkedList<>();
list.add(1); list.add(2); list.add(3); list.add(4);
visualize(ljv, list);

LJV ljv = new LJV()
    .setTreatAsPrimitive(Integer.class)
    .highlightChangingArrayElements();

//note that this sets initial capacity to 5!
Deque<Integer> arrayDeque = new ArrayDeque<>(4);
arrayDeque.add(1); arrayDeque.add(2); arrayDeque.add(3);
visualize(ljv, arrayDeque);

        arrayDeque.poll(); //returns 1
        arrayDeque.poll(); //returns 2
        visualize(ljv, arrayDeque);

    arrayDeque.add(4); arrayDeque.add(5); arrayDeque.add(6);
    visualize(ljv, arrayDeque);

List<Integer> list = IntStream.range(0, 16)
                     .boxed()
                     .collect(Collectors.toList());
Collections.shuffle(list);
visualize(new LJV().setTreatAsPrimitive(Integer.class),
          list.toArray());

LJV ljv = new LJV().setTreatAsPrimitive(Integer.class)
                .setIgnoreNullValuedFields(true)
                .highlightChangingArrayElements();
PriorityQueue<Integer> q = new PriorityQueue<>(16);
q.addAll(list);
visualize(ljv, q);

q.poll();

q.poll();

q.poll();

q.add(1);

LJV ljv = new LJV()
    .setIgnoreNullValuedFields(true)
    .setTreatAsPrimitive(Integer.class)
    .setTreatAsPrimitive(String.class);

Map<String, Integer> map = new HashMap<>();
map.put("one", 1);   map.put("two", 2);
map.put("three", 3); map.put("four", 4);
visualize(ljv, map);

LJV ljv = new LJV()
    .setIgnoreNullValuedFields(true)
    .setTreatAsPrimitive(Integer.class)
    .setTreatAsPrimitive(String.class)
    .addIgnoreField("value")
    .addFieldAttribute("prev", "constraint=false,color=green")
    .addFieldAttribute("next", "constraint=false,color=green")
    .addObjectAttributesProvider(Main::redBlackForHM);

//redBlackForHM: red ? "color=red" : "color=black";

List<String> collisions =
    new HashCodeCollision().genCollisionString(7);
Map<String, Integer> map = new HashMap<>();

for (int i = 0; i < len; i++) {
    map.put(collisions.get(i), i);
}
visualize(ljv, map);

static final class TreeNode<K,V> extends LinkedHashMap.Entry<K,V> {
    TreeNode<K,V> parent;  // red-black tree links
    TreeNode<K,V> left;
    TreeNode<K,V> right;
    TreeNode<K,V> prev;    // needed to unlink next upon deletion
    boolean red;

Map<String, Integer> map = new LinkedHashMap<>(5, 0.8f,
                    /*accessOrder:*/ true);
map.put("one", 1);   map.put("two", 2);
map.put("three", 3); map.put("four", 4);

map.get("two");

ljv = new LJV().setIgnoreNullValuedFields(true);

Map.of(1, 'A', 2, 'B', 3, 'C', 4, 'D'));

 Map.of("aaa", 1, "abB", 2, "bBa", 3)

Map<String, Integer> map =
                new ConcurrentHashMap<String, Integer>(
                        /*initialCapacity:*/16 ,
                        /*loadFactor:*/0.75f,
                        /*concurrencyLevel:*/8);

map.put("one", 1);
map.put("two", 2);
map.put("three", 3);
map.put("four", 4);
map.put("five", 5);
visualize(map);

LJV ljv = new LJV()
    .setTreatAsPrimitive(Integer.class)
    .setTreatAsPrimitive(String.class)
    .setIgnoreNullValuedFields(true)
    .addIgnoreField("color")
    .addObjectAttributesProvider(Main::redBlack);

    //color ? black : red

Map<String, Integer> map = new TreeMap<>();
map.put("one", 1);        map.put("two", 2);
map.put("three", 3);      map.put("four", 4);
map.put("five", 3);       map.put("six", 4);
visualize(ljv, map);