BijectiveMap - duplicate before implementing Map interface [1035371]

< > BotCompany Repo | #1035371 // BijectiveMap - duplicate before implementing Map interface

JavaX fragment (include)

// no null keys or null values
sclass BijectiveMap<A, B> {
  new Map<A, B> forward;
  new Map<B, A> backward;
  
  void put(A a, B b) {
    assertNotNull(a);
    assertNotNull(b);
    A oldKey = backward.get(b);
    if (eq(oldKey, a))
      ret; // nothing to do
    if (oldKey != null)
      forward.remove(oldKey); // remove old mapping
      
    // add/overwrite new mapping
    forward.put(a, b);
    backward.put(b, a);
  }
  
  void remove(A a) {
    B b = forward.get(a);
    if (b == null)
      ret; // nothing to do
    forward.remove(a);
    backward.remove(b);
  }
  
  B get(A a) {
    ret forward.get(a);
  }
  
  A inverseGet(B b) {
    ret backward.get(b);
  }
  
  Set<A> keySet() { ret immutableSet(forward.keySet()); }
  Set<B> valueSet() { ret immutableSet(backward.keySet()); }
  
  int size() { ret forward.size(); }
  
  Map<A, B> forwardMap() { ret immutableMap(forward); }
  Map<B, A> backwardMap() { ret immutableMap(backward); }
}

Author comment

Began life as a copy of #1035059

Travelled to 2 computer(s): mowyntqkapby, mqqgnosmbjvj

Snippet ID:

#1035371

Snippet name:

BijectiveMap - duplicate before implementing Map interface

Eternal ID of this version:

#1035371/1

Text MD5:

fd50962b6163b3229d5f91fa4ad39bbd

Author:

stefan

Category:

javax

Type:

JavaX fragment (include)

Public (visible to everyone):

Yes

Archived (hidden from active list):

Created/modified:

2022-05-03 12:36:40

Source code size:

1000 bytes / 43 lines

Pitched / IR pitched:

No / No

Views / Downloads:

96 / 110

Referenced in:

[show references]

1	// no null keys or null values
2	sclass BijectiveMap<A, B> {
3	new Map<A, B> forward;
4	new Map<B, A> backward;
5
6	void put(A a, B b) {
7	assertNotNull(a);
8	assertNotNull(b);
9	A oldKey = backward.get(b);
10	if (eq(oldKey, a))
11	ret; // nothing to do
12	if (oldKey != null)
13	forward.remove(oldKey); // remove old mapping
14
15	// add/overwrite new mapping
16	forward.put(a, b);
17	backward.put(b, a);
18	}
19
20	void remove(A a) {
21	B b = forward.get(a);
22	if (b == null)
23	ret; // nothing to do
24	forward.remove(a);
25	backward.remove(b);
26	}
27
28	B get(A a) {
29	ret forward.get(a);
30	}
31
32	A inverseGet(B b) {
33	ret backward.get(b);
34	}
35
36	Set<A> keySet() { ret immutableSet(forward.keySet()); }
37	Set<B> valueSet() { ret immutableSet(backward.keySet()); }
38
39	int size() { ret forward.size(); }
40
41	Map<A, B> forwardMap() { ret immutableMap(forward); }
42	Map<B, A> backwardMap() { ret immutableMap(backward); }
43	}